Weekly Update ( 2021 Week 7 )

Week 7 and things are about to get really busy for in-field scouting! Be sure to catch the Insect of the Week – it’s wheat midge! This week find updates to predictive model outputs for grasshoppers, wheat midge, bertha armyworm, cereal leaf beetle, alfalfa weevil, and diamondback moth plus a lot more to help prepare for in-field scouting!

Stay safe and good scouting to you!

Questions or problems accessing the contents of this Weekly Update?  Please contact us so we can connect you to our information. Past “Weekly Updates” can be accessed on our Weekly Update page.

Weather synopsis ( 2021 Week 7 )

TEMPERATURE: This past week (June 7-13, 2021), weekly temperatures were above normal and rainfall in eastern Saskatchewan and Manitoba were above normal. The warmest temperatures were observed across Manitoba and Saskatchewan (Fig. 1). Across the prairies, the average 30-day (May 15 – June 13) temperature was 1 °C warmer than climate normal values. Warmest temperatures were observed across southern Manitoba (Fig. 2). The 2021 growing season (April 1 – June 13, 2021) has been characterized by near normal temperatures (Fig. 3).

Figure 1. 7-day average temperature (°C) observed across the Canadian prairies for the period of June 7 -13, 2021.
Figure 2. 30-day average temperature (°C) observed across the Canadian prairies for the period of May 15 – June 13, 2021.
Figure 3. Growing season average temperature (°C) observed across the Canadian prairies for the period of April 1 – June 13, 2021.

Growing degree day (GDD) maps for Base 5 ºC and Base 10 ºC (April 1-Jun14, 2021) can be viewed by clicking the hyperlinks. Over the past 7 days (June 10-16, 2021), the lowest temperatures recorded across the Canadian prairies ranged from < -32 to >8 °C while the highest temperatures observed ranged from <19 to >35 °C. Access these maps and more using the AAFC Drought Watch webpage interface.

PRECIPITATION: This week, the highest rainfall amounts were reported across eastern Saskatchewan and most of Manitoba. Minimal rainfall was reported across most of Alberta (Fig. 4). Rainfall amounts for the period of May 15-June 13 (30-day accumulation) were above normal (150% of long-term average values). Rainfall amounts have been above normal for northeastern Alberta, northwestern and southeastern Saskatchewan, and western Manitoba. Well above normal rain was reported for Lloydminster, Regina, and Brandon regions. Below normal rainfall amounts were reported for the Peace River region and southern Alberta (Fig. 5). Average growing season (April 1 – June 13) precipitation was 116% of normal with the greatest precipitation occurring across eastern Saskatchewan, including Regina and an area extending from Brandon to Winnipeg. Below normal rainfall has been reported across western Saskatchewan and southern Alberta (Fig. 6).

Figure 4 . 7-day cumulative rainfall (mm) observed across the Canadian prairies for the period of June 7 -13, 2021.
Figure 5. 30-day cumulative rainfall (mm) observed across the Canadian prairies for the period of May 15 – June 13, 2021
Figure 6. Growing season cumulative rainfall (mm) observed across the Canadian prairies for the period of April 1-June 13, 2021.

The maps above are all produced by Agriculture and Agri-Food Canada. Growers can bookmark the AAFC Current Conditions Maps for the growing season. Historical weather data can be access at the AAFC Drought Watch Historical website, Environment Canada’s Historical Data website, or your provincial weather network.

Weekly Wind Trajectory Report for June 15 ( 2021 Week 7 )

Access background information for how and why wind trajectories are monitored in this post.

1. REVERSE TRAJECTORIES (RT)
Similar to last week, this week there were an increasing number of reverse trajectories moving north from the Pacific Northwest (Idaho, Oregon and Washington) (Fig. 1). Though this US region can be a source of diamondback moths (DBM), the ECCC models predict air movement, not actual occurrence of diamondback moths. Fields (and DBM traps) should be monitored for DBM adults and larvae.

Figure 1. The average number (based on a 5 day running average) of reverse trajectories that have crossed the prairies for the period of May 15 – June 15, 2021.

a. Pacific Northwest (Idaho, Oregon, Washington) – This week (June 11-15, 2021) there were 109 trajectories (versus 106 last week) that crossed Alberta, Manitoba and Saskatchewan (Fig. 2).

Figure 2. Total number of dates with reverse trajectories originating over the Pacific Northwest (Idaho, Oregon, and Washington) and have crossed the prairies between March 24 and June 15, 2021.

b. Mexico and southwest USA (Texas, California) – Compared to previous years, there has been a noticeable increase in number of trajectories from the southern US. The majority of these trajectories have crossed Manitoba and eastern Saskatchewan (Fig. 3). This week (June 11-15, 2021) there have been 11 trajectories (10 last week) that originated in Mexico or the southwest USA that have crossed the prairies.

Figure 3. The total number of dates with reverse trajectories originating over Mexico, California and Texas and have crossed the prairies between March 24 and June 15, 2021.

c. Oklahoma and Texas – The majority of these trajectories passed over Manitoba and eastern Saskatchewan (Fig. 4). This week (June 11-15, 2021) there were 18 trajectories (13 last week) originating in Oklahoma or Texas that passed over the prairies.

Figure 4. The total number of dates with reverse trajectories originating over Oklahoma and Texas and have crossed the prairies between March 24 and June 15, 2021.

d. Kansas and Nebraska – This week (June 11-15, 2021) there were 20 trajectories (19 last week) that originated in Kansas or Nebraska that passed over the prairies (Fig. 5).

Figure 5. The total number of dates with reverse trajectories originating over Kansas and Nebraska and have crossed the prairies between March 24 and June 15, 2021.

2. FORWARD TRAJECTORIES (FT)
a. This week there was a decrease in the number of forward trajectories predicted to cross the prairies (Fig. 6). The dates on the graph report when the trajectories originated in the USA (blue bars). These trajectories generally require 3-5 days to enter the prairies (red line). The data suggests that there will be increased potential for introduction of DBM to the prairies.

Figure 6. The average number (based on a 5 day running average) of forward trajectories that were predicted to cross the prairies for the period of May 15-June 15, 2021.

Predicted diamondback moth ( 2021 Week 7 )

Diamondback moths (DBM; Plutella xylostella) are a migratory invasive species. Each spring adult populations migrate northward to the Canadian prairies on wind currents from infested regions in the southern or western U.S.A. Upon arrival to the prairies, migrant diamondback moths begin to reproduce and this results in subsequent non-migrant populations that may have three or four generations during the growing season. Model simulations to June 13, 2021 (using a biofix date of May 15, 2021), indicate that the first generation of non-migrant adults are currently emerging across the Canadian prairies (Fig. 1).

Fig. 1 Predicted number of non-migrant generations of diamondback moth (Plutella xylostella) expected to have occurred across the Canadian prairies as of June 13, 2021.

So far, Manitoba, Saskatchewan, Alberta and the BC Peace are all reporting relatively low numbers of intercepted DBM in pheromone traps (read provincial insect pest report links) despite the fact that favourable wind trajectories have passed over the Canadian prairies from southern regions of North America (review wind trajectory reports for 2021). Even so, once DBM are present in an area, it is important to monitor individual canola fields for larvaeWarm growing conditions can quickly translate into multiple generations in a very short time so use the following photos to help identify larvae (Fig. 2), pupae (Fig. 3), or adults (Fig. 4)!

Monitoring: Remove plants in an area measuring 0.1 m² (about 12″ square), beat them onto a clean surface and count the number of larvae (Fig. 2) dislodged from the plant. Repeat this procedure at least in five locations in the field to get an accurate count.

Figure 2. Diamondback larva measuring ~8mm long.
Note brown head capsule and forked appearance of prolegs on posterior.

The economic threshold for diamondback moth in canola at the advanced pod stage is 20 to 30 larvae/ 0.1  (approximately 2-3 larvae per plant).  Economic thresholds for canola or mustard in the early flowering stage are not available. However, insecticide applications are likely required at larval densities of 10 to 15 larvae/ 0.1 m² (approximately 1-2 larvae per plant).

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Figure 3. Diamondback moth pupa within silken cocoon.
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Figure 4. Diamondback moth.

Biological and monitoring information for DBM (including tips for scouting and economic thresholds) is posted by Manitoba Agriculture and Resource DevelopmentSaskatchewan Agriculture, and the Prairie Pest Monitoring Network.  Also, refer to the diamondback moth pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (accessible in either English-enhanced or French-enhanced versions).

Predicted grasshopper development ( 2021 Week 7 )

Model simulations were used to estimate grasshopper (Melanoplus sanguinipes) development as of June 13, 2021. Average development of eggs is 90 % and well ahead of the long-term average of 80 %. As of June 13, the hatch is predicted to be underway across most of the prairies with a prairie average of 45 % (versus 26 % last week). Hatch rates were greater than 75 % across southern Manitoba, Saskatchewan and Alberta. Development in central and Peace River regions of Alberta has been significantly slower than the rest of the prairies (Fig. 1).

Figure 1. Predicted grasshopper (Melanoplus sanguinipes) hatch (%) across the Canadian prairies as of June 13, 2021.

Development of grasshopper nymphs, based on average instar, is greatest across Manitoba (Fig. 2). Above normal temperatures have resulted in the rapid development of grasshopper populations across Manitoba and Saskatchewan. Grasshopper populations south of Winnipeg are predicted to be mostly in the 3rd and 4th instar stages. Nymph development, as of June 13, 2021, is greater than long-term average values across most of the prairies (Fig. 3).

Figure 2 Predicted grasshopper (Melanoplus sanguinipes) development, presented as the average instar, across the Canadian prairies as of June 13, 2021.
Fig. 3. Long-term average predicted grasshopper (Melanoplus sanguinipes) development, presented as the average instar, across the Canadian prairies as of June 15 based on climate normals data.

The model was projected to June 29 to determine potential development at Saskatoon and Winnipeg over the next two weeks. Results suggest that by June 29, Saskatoon populations will primarily be in the third and fourth instar with first appearance of fifth instar nymphs (Fig. 4) whereas near Winnipeg development is predicted to be faster, with populations being mostly in the fourth and fifth instars (Fig. 5). Producers are advised to monitor roadsides and field margins to assess the development and densities of local grasshopper populations.

Figure 4. Predicted development, presented as the average instar, of Melanoplus sanguinipes populations near Saskatoon, Saskatchewan as of June 13, 2021 (projected to June 29, 2021).
Figure 5. Predicted development, presented as the average instar, of Melanoplus sanguinipes populations near Winnipeg, Manitoba as of June 13, 2021 (projected to June 29, 2021).

Grasshopper Scouting Steps:
● Measure off a distance of 50 m on the level road surface and mark both starting and finishing points using markers or specific posts on the field margin.
● Start at one end in either the field or the roadside and walk toward the other end of the 50 m, making some disturbance with your feet to encourage any grasshoppers to jump.
● Grasshoppers that jump/fly through the field of view within a one-meter width in front of the observer are counted.
● A meter stick can be carried as a visual tool to give perspective for a one-meter width. However, after a few stops, one can often visualize the necessary width and a meter stick may not be required. Also, a hand-held counter can be useful in counting while the observer counts off the required distance.
● At the endpoint, the total number of grasshoppers is divided by 50 to give an average per meter. For 100 m, repeat this procedure.
● Compare counts to the following damage levels associated with pest species of grasshoppers:
0-2 per m² – None to very light damage
2-4 per m² – Very light damage
4-8 per m² – Light damage
8-12 per m² – Action threshold in cereals and canola
12-24 per m² – Severe damage
24 per m² – Very severe damage
For lentils at flowering and pod stages, >2 per m² will cause yield loss.
For flax at boll stages, >2 per m² will cause yield loss.

Biological and monitoring information (including tips for scouting and economic thresholds) related to grasshoppers in field crops is posted by Manitoba Agriculture and Resource DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture, and the Prairie Pest Monitoring Network.  Also, refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (accessible in either English-enhanced or French-enhanced versions).

Predicted bertha armyworm development ( 2021 Week 7 )

Model simulations to June 13, 2021, indicate that bertha armyworm (BAW) (Mamestra configurata) pupal development is greater than 75% (Fig. 1). Populations are predominantly in the pupal stage (Fig. 2).

Figure 1. Predicted bertha armyworm (Mamestra configurata) pupal development (%) across the Canadian prairies as of June 13, 2021.
Figure 2. Predicted percent of bertha armyworm (Mamestra configurata) population that is in the pupal stage (% of population) across the Canadian prairies as of June 13, 2021.

Model simulations indicate that BAW adult emergence has begun across southern areas of Manitoba and Saskatchewan (Fig. 3). Based on pupal development, adult emergence should occur across most of the prairies over the next few days.

Figure 3. Predicted percent of bertha armyworm (Mamestra configurata) population that is in the adult stage (% of population) across the Canadian prairies as of June 13, 2021.

Model projections to June 30 predict that development near Winnipeg is more advanced than at Lacombe (Figs. 4 and 5). The model predicts that oviposition has begun near Winnipeg and that egg hatch will begin next week in fields.

Figure 4. Predicted development of bertha armyworm (Mamestra configurata) populations near Winnipeg, Manitoba as of June 13, 2021 (projected to June 29, 2021).
Figure 5. Predicted development of bertha armyworm (Mamestra configurata) populations near Lacombe, Alberta as of June 13, 2021 (projected to June 29, 2021).

Refer to the PPMN Bertha armyworm monitoring protocol for help when performing in-field scouting.  Use the images below (Fig. 6) to learn to identify the various stages.  Review the 2019 Insect of the Week which featured bertha armyworm and its doppelganger, the clover cutworm! 

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Figure 6. The egg stage (A), larval stage (B), pupal stage (C), and adult stage (D) of bertha armyworm. Photos: Jonathon Williams (AAFC-Saskatoon).

Biological and monitoring information related to bertha armyworm in field crops is posted by the provinces of ManitobaSaskatchewanAlberta and the Prairie Pest Monitoring Network. Also, refer to the bertha armyworm pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is a free downloadable document as both an English-enhanced or French-enhanced version.

Predicted cereal leaf beetle development ( 2021 Week 7 )

The cereal leaf beetle (CLB) (Oulema melanopus) model predicts that larval development varies across the prairies. The graph predicts development at Lethbridge (Fig. 1). The simulation indicates that populations in southern Alberta should be in the second and third instar. The appearance of pupae is expected to occur by the end of the month across southern Alberta.

Figure 1. Predicted status of cereal leaf beetle (Oulema melanopus) populations near Lethbridge, Alberta as of June 13, 2021 (projected to June 29, 2021).

Cereal leaf beetle scouting

Give priority to the following factors when selecting monitoring sites:
□ Choose fields and sections of the fields with past or present damage symptoms.
□ Choose fields that are well irrigated (leaves are dark green in color), including young, lush crops. Areas of a field that are under stress and not as lush (yellow) are less likely to support CLB.
□ Monitor fields located along riparian corridors, roads and railroads.
□ Survey field areas that are close to brush cover or weeds, easy to access, or are nearby sheltered areas such as hedge rows, forest edges, fence lines, etc.

Focus site selection on the following host plant priorities:
□ First – winter wheat. If no winter wheat is present then;
□ Second – other cereal crops (barley, wheat, oats, and rye). If no cereal crops are present then;
□ Third – hay crops. If no hay crops or cereal crops are present then;
□ Fourth – ditches and water corridors

Sweep-net Sampling for Adults and Larvae:
● A sweep is defined as a one pass (from left to right, executing a full 180 degrees) through the upper foliage of the crop using a 37.5 cm diameter sweep-net.
● A sample is defined as 100 sweeps taken at a moderate walking pace collected 4-5 meters inside the border of a field.
● At each site, four samples should be collected, totaling 400 sweeps per site. The contents of each sample should be visually inspected for life stages of CLB and all suspect specimens should be retained for identification.
● Because the CLB larvae are covered in a sticky secretion, they are often covered in debris and are very difficult to see within a sweep-net sample.
● To help determine the presence of CLB, place the contents of the sweep net into a large plastic bag for observation.

Visual Inspection: Both the adults and larvae severely damage plants by chewing out long strips of tissue between the veins of leaves (Fig. 1), leaving only a thin membrane. When damage is extensive, leaves turn whitish.

Lifecycle and Damage:

Larva: The larvae hatch in about 5 days and feed for about 3 weeks, passing through 4 growth stages (instars). The head and legs are brownish-black; the body is yellowish. Larvae are usually covered with a secretion of mucus and fecal material, giving them a shiny black, wet appearance (Fig. 2).  When the larva completes its growth, it drops to the ground and pupates in the soil. 

Figure 2.  Larval stage of Oulema melanopus with characteristic feeding damage visible on leaf (Photo: M. Dolinski).

Pupa: Pupal colour varies from a bright yellow when it is first formed, to the colour of the adult just before emergence. The pupal stage lasts 2 – 3 weeks. Adult beetles emerge and feed for a couple of weeks before seeking overwintering sites. There is one generation per year.

Adult: Adult cereal leaf beetles (CLB) have shiny bluish-black wing-covers (Fig. 3). The thorax and legs are light orange-brown. Females (4.9 to 5.5 mm) are slightly larger than males (4.4 to 5 mm). They emerge in the spring once temperatures reach 10-15 ºC and the adults are active for about 6 weeks. They usually begin feeding on grasses, then move into winter cereals and later into spring cereals. Adult beetles overwinter in and along the margins of grain fields in protected places such as in straw stubble, under crop and leaf litter, and in the crevices of tree bark. They favour sites adjacent to shelter belts, deciduous and conifer forests.

Figure 3. Adult Oulema melanopus measure 4.4-5.5 mm long (Photo: M. Dolinski).

Fact sheets for CLB are published by the province of Alberta and available from the Prairie Pest Monitoring Network. Also, access the Oulema melanopus page from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible in either English-enhanced or French-enhanced versions).

Predicted alfalfa weevil development ( 2021 Week 7 )

Model simulations for alfalfa weevil (AAW) (Hypera postica) predict, as of June 13, that alfalfa weevil populations should be in the third larval instar (Fig. 1). Fourth instar larvae are predicted to occur across southeastern Saskatchewan and southern Manitoba.

Figure 1. Predicted percent of Hypera postica (alfalfa weevil) population in the third instar stage as of June 13, 2021.

The following graphs indicate that development is more advanced near Brandon (Fig. 2) than Swift Current (Fig. 3). Simulation runs indicate that by June 29, southern Manitoba populations will be in pupal stage whereas Swift Current populations are predicted to be in the fourth instar and pupal stages.

Figure 2. Predicted status of alfalfa weevil (Hypera postica) development for populations near Brandon, Manitoba as of June 13, 2021 (projected to June 29, 2021).
Figure 3. Predicted status of alfalfa weevil (Hypera postica) development for populations near Swift Current, Saskatchewan as of June 13, 2021 (projected to June 29, 2021).

The larval stage of this weevil feeds on alfalfa leaves in a manner that characterizes the pest as a “skeletonizer” (Fig. 4).  The green larva features a dorsal white line down the length of its body, has a dark brown head capsule, and will grow to 9 mm long.  

Figure 4. Developmental stages of the alfalfa weevil (Hypera postica). Composite image: J. Soroka (AAFC-Saskatoon).

Alfalfa growers are encouraged to check the Alfalfa Weevil Fact Sheet prepared by Dr. Julie Soroka (AAFC-Saskatoon).  Additional information can be accessed by reviewing the Alfalfa Weevil Page extracted from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible in either English-enhanced or French-enhanced versions).

Predicted wheat midge development ( 2021 Week 7 )

Wheat midge (Sitodiplosis mosellana) overwinter as larval cocoons in the soil. Soil moisture conditions in May and June can have significant impacts on wheat midge emergence. Adequate rainfall promotes termination of diapause and movement of larvae to the soil surface where pupation occurs. Insufficient rainfall in May and June can result in delayed movement of larvae to the soil surface. Elliott et al. (2009) reported that wheat midge emergence was delayed or erratic if rainfall did not exceed 20-30 mm during May. Olfert et al. (2016) ran model simulations to demonstrate how rainfall impacts wheat midge population density. The Olfert et al. (2020) model indicated that dry conditions may result in:
a. Delayed adult emergence and oviposition
b. Reduced numbers of adults and eggs

Based on averages across the three provinces, 56% of the wheat midge population is predicted to be in the larval cocoon stage (in the soil) and 44% are in the pupal stage. As a result of suitable temperature and rainfall, wheat midge model simulations indicate that more than 70% of the larval population has moved to the soil surface in central Alberta and northwestern and southeastern Saskatchewan (Fig. 1). Dryer conditions in Manitoba and the Peace River region continue to delay movement of larvae to the soil surface.

Figure 1. Percent of the wheat midge (Sitodiplosis mosellana) larval population that has moved to the soil surface across western Canada, based on weather conditions up to June 13, 2021.

Information related to wheat midge biology and monitoring can be accessed by linking to your provincial fact sheet (Saskatchewan Agriculture or Alberta Agriculture & Forestry).  A review of wheat midge on the Canadian prairies was published by Elliott, Olfert, and Hartley in 2011.  

Alberta Agriculture and Forestry has a YouTube video describing in-field monitoring for wheat midge.  

More information about wheat midge can be found by accessing the pages from the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and Field Guide”.  View ONLY the Wheat midge pages but remember the guide is available as a free downloadable document as both an English-enhanced or French-enhanced version.

Cereal Aphid Manager APP ( 2021 Week 7 )

Aphids can cause significant damage to fields and increase crop losses but low densities in a grain field sometimes have little economic impact on production. This is especially true if the aphid’s natural enemies (beneficial insects) are present in the field because they can keep the aphids under control.

The Cereal Aphid Manager is an easy-to-use mobile app that helps farmers and crop advisors control aphid populations in wheat, barley, oat or rye. It is based on Dr. Tyler Wist’s (AAFC-Saskatoon) Dynamic Action Threshold model. The model treats the grain field as an ecosystem and takes into account many complex biological interactions including:

  • the number of aphids observed and how quickly they reproduce
  • the number of different natural enemies of aphids in the field and how many aphids they eat or parasitize per day
  • the lifecycles of aphids and their enemies taking into account developmental stages, egg laying behaviour, population growth rate, lifespan, etc.

Frequent in-field scouting, supported by the app’s dynamic threshold, allows growers to weigh the above factors and the app predicts what the aphid population will be in seven days and the best time to apply insecticide based on economic thresholds.

To learn more and to download the app (Android or iOS), go to AAFC’s CAM webpage

Nationwide monitoring pilot project for European corn borer ( 2021 Week 7 )

The European corn borer (ECB; Ostrinia nubilalis), has been an important pest of corn and other crops in eastern Canada for nearly a century now but is also known to be a sporadic pest in western Canada. Despite its name, ECB is actually a generalist feeder, having a wide range of hosts. With so many new emerging crops being grown in Canada that are also hosts for ECB (eg. hemp, cannabis, quinoa, hops, millet and others), there is no better time to look at this pest across the Canadian agricultural landscape.

To monitor for ECB nationwide, the Surveillance Working Group of the Canadian Plant Health Council has developed a harmonized monitoring protocol for European corn borer in both English and French. The project aims to generate real-time reporting and annual maps – access a full description of the project and list of key contact persons. The protocol can be used to report ECB eggs, larvae or damage in any host crop across Canada. This harmonized protocol has been designed to complement protocols already in use to make management decisions in order to generate data to compare ECB presence across all of Canada and across host crops.

When scouting corn, quinoa, hemp, millet, potatoes, apples, or other crops susceptible to ECB, the Surveillance Working Group of the Canadian Plant Health Council encourages the use of the harmonized monitoring protocol and reporting of the data from fields or research plots using the free Survey123 app (available for both desktop and mobile devices):
• Early to Mid-Season ECB Survey (Before July) – https://arcg.is/0qCCHH (applicable for use in eastern Canada).
• Later Season ECB Survey (July to Pre-Harvest) – https://arcg.is/fSODf (applicable for use in both eastern AND western Canada).

Field heroes ( 2021 Week 7 )

The Field Heroes campaign continues to raise awareness of the role of beneficial insects in western Canadian crops.

Two NEW Field Heroes resources for 2021 include:

  1. Real Agriculture went live in 2021 with Season 2 of the Pest and Predators podcast series!
    NEW – Episode 11 – Free farm labour (June 15, 2021)
    • Episode 10 – Good bugs relocate for work (June 1, 2021)
    • Episode 9 – Secret agents in the stubble (May 18, 2021)
    • Episode 8 – Good vs pea leaf weEVIL (May 4, 2021)
    • Episode 7 – Powerful parasitoids: Better than fiction (April 20, 2021)
    • Recap of SEASON 1: Episode 1 – Do you know your field heroes? Episode 2 – An inside look at the Prairie Pest Monitoring Network. Episode 3 – How much can one wasp save you? Episode 4 – Eat and be eaten — grasshoppers as pests and food Episode 5 – Killer wasp has only one target — wheat stem sawfly Episode 6 – Plentiful parasitoids
  2. The NEW Pests and Predators Field Guide is filled with helpful images for quick insect identification and plenty of tips to manage the pests AND natural enemies in your fields. Claim your free copy at http://fieldheroes.ca/fieldguide/ or download for free to arm your in-field scouting efforts!

Access ALL the Field Heroes links here and be sure to follow @FieldHeroes!

Monarch migration ( 2021 Week 7 )

Track the migration of the Monarch butterflies as they move north by checking the 2021 Monarch Migration Map!  A screenshot of the map has been placed below as an example (retrieved 17Jun2021) but follow the hyperlink to check the interactive map.  They’ve reached Saskatchewan and southern Alberta!

Access this Post to help you differentiate between Monarchs and Painted Lady Butterflies!

Visit the Journey North website to learn more about migration events in North America and visit their monarch butterfly website for more information related to this amazing insect. 

Provincial insect pest report links ( 2021 Week 7 )

Provincial entomologists provide insect pest updates throughout the growing season so link to their information:

MANITOBA’S Crop Pest Updates for 2021 are now available – access the June 16, 2021 report here. Be sure to bookmark their Crop Pest Update Index to readily access these reports! Also, bookmark their insect pest homepage to access fact sheets and more!
Bertha armyworm pheromone trap monitoring update for MB – Cumulative counts arising from weekly data will soon be available.
Diamondback moth pheromone trap monitoring update for MB – Refer to the summary updated twice a week. So far, only 59 traps have intercepted moths and the highest cumulative count is 135 moths near The Pas. Access the summary (as of June 8, 2021).

SASKATCHEWAN’S Crop Production News have begun to roll out for 2021 and are accessible now! Access Issue #1 online which includes a crop protection laboratory update including how to submit samples, information on curculios on fruit crops, and information for scouting flea beetles and assessing damage. Be sure to bookmark their insect pest homepage to access important information!
Bertha armyworm pheromone trap monitoring update for SK – Cumulative counts arising from weekly data will soon be available.
Diamondback moth pheromone trap monitoring update for SK – follow this link to find current DBM counts. At this point, extremely low numbers have been intercepted but monitoring continues. Province-wide, <45 moths have been intercepted so far (2021Jun10 Carter, pers. comm.).

ALBERTA’S Insect Pest Monitoring Network webpage links to insect survey maps, live feed maps, and insect trap set-up videos and more. There is also a Major Crops Insect webpage. The new webpage does not replace the Insect Pest Monitoring Network page. Remember, AAF’s Agri-News occasionally includes insect-related information or Twitter users can connect to #ABBugChat Wednesdays at 10:00 am.
Bertha armyworm pheromone trap monitoring update for AB – Cumulative counts arising from weekly data are starting to roll in so refer to the Live Map as data becomes available.
Diamondback moth pheromone trap monitoring update for AB – Refer to the Live Map which still reports extremely low numbers of moths intercepted so far (<45 province-wide as of 17Jun2021).
Cutworm reporting tool – Refer to the Live Map which still reports only four sites with cutworms (as of 17Jun2021).

Crop report links ( 2021 Week 7 )

Click the provincial name below to link to online crop reports produced by:
Manitoba Agriculture and Resource Development (subscribe to receive OR access a PDF copy of the June 15 2021 report).
Saskatchewan Agriculture (or access a PDF copy of the June 8-14, 2021 report).
Alberta Agriculture and Forestry (or access a PDF copy of the June 8, 2021 report).

The following crop reports are also available:
• The United States Department of Agriculture (USDA) produces a Crop Progress Report (access a PDF copy of the June 14, 2021 edition).
• The USDA’s Weekly Weather and Crop Bulletin (access a PDF copy of the Jun 15, 2021 edition).

Previous posts ( 2021 Week 7 )

As the growing season progresses, the various Weekly Update topics move on and off the priority list for in-field scouting but they should be kept at hand to support season-long monitoring. Click to review these earlier 2021 Posts (organized alphabetically):
2020-2021 Risk and forecast maps
Crop protection guides (Wk03)
Cutworms (Wk02)
Flea beetles (Wk02)
Flea beetles – predicted geographic distribution and abundance (Wk04)
Ladybird beetles (Wk03)
Pea leaf weevil (Wk03)
Scouting charts – canola and flax (Wk03)
Slugs and their parasites (Wk04)
Weather radar mapping interface (Wk06))
Wind trajectories for monitoring insect movement (Wk02)
Wireworms (Wk02)

Weekly Update ( 2021 Week 6 )

Week 6 and things are hopping – literally! Be sure to catch the Insect of the Week – it’s bertha armyworm! This week find updates to predictive model outputs for grasshoppers, wheat midge, bertha armyworm, cereal leaf beetle, and alfalfa weevil plus a lot more to help prepare for in-field scouting!

If you missed it, June 8th was National Insect Day here in Canada but you can still catch up on #NationalInsectDay or check out the #NationalPictureChallenge via Twitter! And….. we love this animated Brood X guide!

Stay safe and good scouting to you!

Questions or problems accessing the contents of this Weekly Update?  Please contact us so we can connect you to our information. Past “Weekly Updates” can be accessed on our Weekly Update page.

Weekly Wind Trajectory Report for June 10 ( 2021 Week 6 )

Access background information for how and why wind trajectories are monitored in this post.

1. REVERSE TRAJECTORIES (RT)
This past week (in particular June 9 and 10) there were an increasing number of reverse trajectories moving north from the Pacific Northwest (Idaho, Oregon and Washington), Texas, Oklahoma, Kansas and Nebraska (Fig. 1). Though these US regions can be a source of diamondback moths (DBM), the ECCC models predict air movement, not actual occurrence of diamondback moths. Fields (and DBM traps) should be monitored for DBM adults and larvae.

Figure 1. The average number (based on a 5 day running average) of reverse trajectories that have crossed the prairies for the period of May 15 – June 10 2021.

a. Pacific Northwest (Idaho, Oregon, Washington) – This week there have been 106 trajectories (53 last week) that have crossed Alberta, Manitoba and Saskatchewan. This growing season, PNW trajectories have crossed all parts of the prairies (Fig. 2).

Figure 2. Total number of dates with reverse trajectories originating over the Pacific Northwest (Idaho, Oregon, and Washington) and have crossed the prairies between March 24 and June 10, 2021.

b. Mexico and southwest USA (Texas, California) – Compared to previous years, there has been a noticeable increase in the number of trajectories from the southern US. The majority of these trajectories have crossed Manitoba and eastern Saskatchewan (Fig. 3). This week there have been 10 trajectories (0 last week) that originated in Mexico or the southwest USA that have crossed the prairies (Fig. 3).

Figure 3. The total number of dates with reverse trajectories originating over Mexico, California and Texas and have crossed the prairies between March 24 and June 10, 2021.

c. Oklahoma and Texas – This week there have been 13 trajectories (0 last week) originating in Oklahoma or Texas that have passed over the prairies (Fig. 4).

Figure 4. The total number of dates with reverse trajectories originating over Oklahoma and Texas and have crossed the prairies between March 24 and June 10, 2021.

d. Kansas and Nebraska – This week there were 19 trajectories (versus 1 last week) that originated in Kansas or Nebraska that passed over the prairies (Fig. 5). Relative to the reverse trajectories associated with Oklahoma and Texas (Fig. 4), the trajectories from Kansas and Nebraska have crossed further into Alberta (Fig. 5).

Figure 5. The total number of dates with reverse trajectories originating over Kansas and Nebraska and have crossed the prairies between March 24 and June 10, 2021.

2. FORWARD TRAJECTORIES (FT)
a. Continuing a trend that began last week, this week there was an increase in the number of forward trajectories predicted to cross the prairies (Fig. 6). The dates on the graph report when the trajectories originated in the USA (blue bars). These trajectories generally require 3-5 days to enter the prairies (red line). The data suggests that there will be increased potential for introduction of DBM to the prairies.

Figure 6. The average number (based on a 5-day running average) of forward trajectories that were predicted to cross the prairies for the period of May 15-June 10, 2021.

Weather synopsis ( 2021 Week 6 )

TEMPERATURE: This past week (May 31 – June 6, 2021) extremely warm conditions resulted in weekly average temperatures that were well above normal (Fig. 1). The warmest temperatures were observed across Manitoba and eastern Saskatchewan (Fig. 1).

Figure 1. 7-day average temperature (°C) observed across the Canadian prairies for the period of May 31 – June 6, 2021.

Across the prairies, the average 30-day (May 8 – June 6) temperature was almost 2.5 °C warmer than the previous week and 1.3 °C greater than climate normal values. Warmest temperatures were observed across southern Manitoba (Table 1; Fig. 2).

Figure x. 30-day average temperature (°C) observed across the Canadian prairies for the period of May 8 – June 6, 2021.

The 2021 growing season (April 1 – June 6) has been characterized by near-normal temperatures. Temperatures have been warmest for southern Manitoba and southern Alberta (Table 2; Fig. 3).

Figure 3. Growing season average temperature (°C) observed across the Canadian prairies for the period of April 1 – June 6, 2021.

Follow the hyperlinks to access AAFC Drought Watch maps reflecting the growing degree day (GDD) for Base 5 ºC, (April 1-June 7, 2021) and for Base 10 ºC (April 1-June 7, 2021). Over the past 7 days (June 3-9, 2021), the lowest temperatures recorded ranged from <0 to >12 °C while the highest temperatures observed across the Canadian prairies ranged from <10 to >36 °C.

PRECIPITATION: This week, the highest rainfall amounts were reported across northwest Saskatchewan and central Alberta while weekly rainfall amounts less than 2 mm was reported across a large area that extended from western Manitoba, across most of Saskatchewan, to southern Alberta. Extreme dry conditions were reported across the Peace River region (Fig. 4).

Figure 4 . 7 day cumulative rainfall (mm) observed across the Canadian prairies for the period of May 31 – June 6, 2021.

Rainfall amounts for the period of May 8 to June 6 (30-day accumulation) were above normal (110 % of long-term average values). Rainfall amounts have been near normal to above normal for large areas of Alberta as well as northwest and southeast Saskatchewan. Well-above-normal rain was reported for Edmonton and Regina. Below normal rainfall amounts were reported for central and northern areas of the Peace River region and across Manitoba (Table 1; Fig. 5).

Figure 5. 30-day cumulative rainfall (mm) observed across the Canadian prairies for the period of May 8 – June 6, 2021.

Average growing season (April 1 – June 6) precipitation was 94 % of normal with the greatest precipitation occurring near Edmonton and across eastern Saskatchewan, including Regina. Most of Manitoba and the Peace River region have had 60 % or less than normal precipitation during the 2021 growing season (Table 2; Fig. 6).

Figure 6. Growing season cumulative rainfall (mm) observed across the Canadian prairies for the period of April 1 – June 6, 2021.

The maps above are all produced by Agriculture and Agri-Food Canada. Growers can bookmark the AAFC Current Conditions Maps for the growing season. Historical weather data can be access at the AAFC Drought Watch Historical website, Environment Canada’s Historical Data website, or your provincial weather network.

Access ALL the PPMN’s Wind Trajectory reports (Weekly and Daily).

Access Environment and Climate Change Canada’s weather radar mapping interface. Options to access preceeding precipitation events include clicking off either an 1 or 3 hours time interval, using an 8-colour or 14-colour index. or changing the base map.

Predicted grasshopper development ( 2021 Week 6 )

Model simulations were used to estimate grasshopper (Melanoplus sanguinipes) development as of June 6, 2021. Average development of eggs is 86 % and is well ahead of the long term average of 73 %. Last week’s warm conditions across southeastern SK and southern Manitoba have been responsible for advanced development of eggs near Regina, Saskatoon, Brandon, and Winnipeg. Egg development is predicted to exceed 90 % across most of the southern prairies (Fig. 1).

Figure 1. Predicted grasshopper (Melanoplus sanguinipes) embryological development (%) across the Canadian prairies as of June 6, 2021.

As of June 6, hatch was predicted to be occurring across most of the prairies (overall average was 26 %) with hatch rates approaching 30-45 % across southern Manitoba and Saskatchewan (Fig. 2). The model was projected to June 22 to determine potential development at Regina and Swift Current over the next two weeks (Figs. 3 and 4). Results suggest that by June 22, Regina populations will primarily be in the third instar, with first appearance of fourth instars. Development near Swift Current is predicted to be slower, with populations being mostly in the first and second instars.

Warm, dry conditions continue to persist across Manitoba. This may result in conditions conducive to crop damage from grasshoppers as hatch progresses in June. Producers are advised to monitor roadsides and field margins to assess development and densities of local grasshopper populations.

Figure 2. Predicted grasshopper (Melanoplus sanguinipes) hatch (%) across the Canadian prairies as of June 6, 2021.
Figure 3. Predicted development of Melanoplus sanguinipes populations near Regina, Saskatchewan as of June 6, 2021 (projected to June 22, 2021).
Figure 4. Predicted development of Melanoplus sanguinipes populations near Swift Current, Saskatchewan as of June 6, 2021 (projected to June 22, 2021).

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture and Resource DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (accessible in either English-enhanced or French-enhanced versions).

Predicted wheat midge development ( 2021 Week 6 )

Wheat midge (Sitodiplosis mosellana) overwinter as larval cocoons in the soil. Soil moisture conditions in May and June can have significant impacts on wheat midge emergence. Adequate rainfall promotes termination of diapause and movement of larvae to the soil surface where pupation occurs. Insufficient rainfall in May and June can result in delayed movement of larvae to the soil surface. Elliott et al. (2009) reported that wheat midge emergence was delayed or erratic if rainfall did not exceed 20-30 mm during May. Olfert et al. (2016) ran model simulations to demonstrate how rainfall impacts wheat midge population density. The Olfert et al. (2020) model indicated that dry conditions may result in:
a. Delayed adult emergence and oviposition
b. Reduced numbers of adults and eggs

As of June 6, 2021, wheat midge model runs indicate that recent rainfall in central Alberta and northwestern and southeastern Saskatchewan has resulted in movement of more than 30 % of the larval population to the soil surface (Fig. 1). Dryer conditions in other parts of Saskatchewan, Manitoba and most of the Peace River region continue to delay movement of larvae to the soil surface. If dry conditions persist, this should result in delayed pupation and adult emergence.

Figure 1. Percent of wheat midge larval population (Sitodiplosis mosellana) that has moved to the soil surface across western Canada, based on weather conditions up to June 6, 2021.

Information related to wheat midge biology and monitoring can be accessed by linking to your provincial fact sheet (Saskatchewan Agriculture or Alberta Agriculture & Forestry).  A review of wheat midge on the Canadian prairies was published by Elliott, Olfert, and Hartley in 2011.  

Alberta Agriculture and Forestry has a YouTube video describing in-field monitoring for wheat midge.  

More information about wheat midge can be found by accessing the pages from the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and Field Guide”.  View ONLY the Wheat midge pages but remember the guide is available as a free downloadable document as both an English-enhanced or French-enhanced version.

Predicted bertha armyworm development ( 2021 Week 6 )

Model simulations to June 6, 2021, indicate that bertha armyworm (BAW) (Mamestra configurata) pupal development ranges from 60-90 % across the prairies (Fig. 1). BAW traps should be placed in fields when pupal development exceeds 80 %. Table 1 provides guidelines to determine when traps should be deployed. Based on weather data up to June 6, 2021, BAW adults should begin to emerge by mid to late June.

Figure 1. Predicted bertha armyworm (Mamestra configurata) pupal development across the Canadian prairies as of June 6, 2021.

Model projections to June 30 predict that development near Winnipeg will be more advanced than at Lacombe (Figs. 2 and 3, respectively). The model predicts that egg hatch will begin in mid-June near Winnipeg.

Figure 2. Predicted development of bertha armyworm (Mamestra configurata) populations near Winnipeg, Manitoba as of June 6, 2021 (projected to June 30, 2021).
Figure 3. Predicted development of bertha armyworm (Mamestra configurata) populations near Lacombe, Alberta as of June 6, 2021 (projected to June 30, 2021).

Biological and monitoring information related to bertha armyworm in field crops is posted by the provinces of ManitobaSaskatchewanAlberta and the Prairie Pest Monitoring Network. Also, refer to the bertha armyworm pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is a free downloadable document as both an English-enhanced or French-enhanced version.

Predicted cereal leaf beetle development ( 2021 Week 6 )

The cereal leaf beetle (CLB) (Oulema melanopus) model predicts that larval development is progressing across the prairies. The graphs below provide a comparison of development at Saskatoon (Fig. 1) and at Lethbridge (Fig. 2). The simulation indicates that populations are mostly in the second instar with the initial occurrence of third instar stages expected to occur this week. The simulation predicts that larval development will be complete by the end of the month across central Saskatchewan.

Figure 1. Predicted status of cereal leaf beetle (Oulema melanopus) populations near Saskatoon, Saskatchewan as of June 6, 2021 (projected to June 22, 2021).
Figure 2. Predicted status of cereal leaf beetle (Oulema melanopus) populations near Lethbridge, Alberta as of June 6, 2021 (projected to June 22, 2021).

Fact sheets for CLB are published by the province of Alberta and available from the Prairie Pest Monitoring Network. Also access the Oulema melanopus page from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible in either English-enhanced or French-enhanced versions).

Predicted alfalfa weevil development ( 2021 Week 6 )

Model simulations for alfalfa weevil (AAW) (Hypera postica) predict, as of June 6, that alfalfa weevil populations should be primarily in the second larval instar (Fig. 1). The following graph indicates the predicted development near Brandon (Fig. 2). This week, larval populations in southern Manitoba should be primarily in the second instar. Simulation runs indicate that by June 22, southern Manitoba populations will be in the fourth instar with initial appearance of pupae.

Figure 1. Predicted development of Hypera postica (alfalfa weevil) populations across the prairies as of June 6, 2021.
Figure 2. Predicted status of alfalfa weevil (Hypera postica) development for populations near Brandon, Manitoba as of June 6, 2021 (projected to June 22, 2021).

The larval stage of this weevil feeds on alfalfa leaves in a manner that characterizes the pest as a “skeletonizer” (Fig. 3).  The green larva features a dorsal white line down the length of its body, has a dark brown head capsule, and will grow to 9 mm long.  

Figure 3. Developmental stages of the alfalfa weevil (Hypera postica). Composite image: J. Soroka (AAFC-Saskatoon).

Alfalfa growers are encouraged to check the Alfalfa Weevil Fact Sheet prepared by Dr. Julie Soroka (AAFC-Saskatoon).  Additional information can be accessed by reviewing the Alfalfa Weevil Page extracted from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible in either English-enhanced or French-enhanced versions).

Nationwide monitoring pilot project for European corn borer ( 2021 Week 6 )

The European corn borer (ECB; Ostrinia nubilalis), has been an important pest of corn and other crops in eastern Canada for nearly a century now but is also known to be a sporadic pest in western Canada. Despite its name, ECB is actually a generalist feeder, having a wide range of hosts. With so many new emerging crops being grown in Canada that are also hosts for ECB (eg. hemp, cannabis, quinoa, hops, millet and others), there is no better time to look at this pest across the Canadian agricultural landscape.

To monitor for ECB nationwide, the Surveillance Working Group of the Canadian Plant Health Council has developed a harmonized monitoring protocol for European corn borer in both English and French. The project aims to generate real-time reporting and annual maps – access a full description of the project and list of key contact persons. The protocol can be used to report ECB eggs, larvae or damage in any host crop across Canada. This harmonized protocol has been designed to complement protocols already in use to make management decisions in order to generate data to compare ECB presence across all of Canada and across host crops.

When scouting corn, quinoa, hemp, millet, potatoes, apples, or other crops susceptible to ECB, the Surveillance Working Group of the Canadian Plant Health Council encourages the use of the harmonized monitoring protocol and reporting of the data from fields or research plots using the free Survey123 app (available for both desktop and mobile devices):
• Early to Mid-Season ECB Survey (Before July) – https://arcg.is/0qCCHH (applicable for use in eastern Canada).
• Later Season ECB Survey (July to Pre-Harvest) – https://arcg.is/fSODf (applicable for use in both eastern AND western Canada).

Field heroes ( 2021 Week 6 )

The Field Heroes campaign continues to raise awareness of the role of beneficial insects in western Canadian crops.

Two NEW Field Heroes resources for 2021 include:

  1. Real Agriculture went live in 2021 with Season 2 of the Pest and Predators podcast series!
    NEWEpisode 10Good bugs relocate for work (June 1, 2021)
    Episode 9Secret agents in the stubble (May 18, 2021)
    Episode 8Good vs pea leaf weEVIL (May 4, 2021)
    Episode 7Powerful parasitoids: Better than fiction (April 20, 2021)
    Recap of SEASON 1: Episode 1 – Do you know your field heroes? Episode 2 – An inside look at the Prairie Pest Monitoring Network. Episode 3 – How much can one wasp save you? Episode 4 – Eat and be eaten — grasshoppers as pests and food Episode 5 – Killer wasp has only one target — wheat stem sawfly Episode 6 – Plentiful parasitoids
  2. The NEW Pests and Predators Field Guide is filled with helpful images for quick insect identification and plenty of tips to manage the pests AND natural enemies in your fields. Claim your free copy at http://fieldheroes.ca/fieldguide/ or download for free to arm your in-field scouting efforts!

Access ALL the Field Heroes links here and be sure to follow @FieldHeroes!

Monarch migration ( 2021 Week 6 )

Track the migration of the Monarch butterflies as they move north by checking the 2021 Monarch Migration Map!  A screenshot of the map has been placed below as an example (retrieved 10Jun2021) but follow the hyperlink to check the interactive map.  They have reached Dauphin MB!

Access this Post to help you differentiate between Monarchs and Painted Lady Butterflies!

Visit the Journey North website to learn more about migration events in North America and visit their monarch butterfly website for more information related to this amazing insect. 

Provincial insect pest report links ( 2021 Week 6 )

Provincial entomologists provide insect pest updates throughout the growing season so link to their information:

MANITOBA’S Crop Pest Updates for 2021 are now available! Access the June 9, 2021 report here. Be sure to bookmark their Crop Pest Update Index to readily access these reports! Also, bookmark their insect pest homepage to access fact sheets and more!
Bertha armyworm pheromone trap monitoring update for MB – Cooperators are deploying pheromone traps and weekly data will soon be available.
Diamondback moth pheromone trap monitoring update for MB – Refer to the summary updated twice a week. So far, only 38 traps have intercepted moths and only double-digit cumulative counts! Access the summary (as of June 8, 2021).

SASKATCHEWAN’S Crop Production News will soon be available. Be sure to bookmark their insect pest homepage to access important information!
Bertha armyworm pheromone trap monitoring update for SK – Cooperators are deploying pheromone traps at sites across the province.
Diamondback moth pheromone trap monitoring update for SK – follow this link to find current DBM counts. At this point, extremely low numbers have been intercepted but monitoring continues. Province-wide, <45 moths have been intercepted so far (2021Jun10 Carter, pers. comm.).

ALBERTA’S Insect Pest Monitoring Network webpage links to insect survey maps, live feed maps, and insect trap set-up videos and more. There is also a Major Crops Insect webpage. The new webpage does not replace the Insect Pest Monitoring Network page. Remember, AAF’s Agri-News occasionally includes insect-related information or Twitter users can connect to #ABBugChat Wednesdays at 10:00 am.
Bertha armyworm pheromone trap monitoring update for AB – Cooperators are deploying pheromone traps so refer to the Live Map as data becomes available.
Diamondback moth pheromone trap monitoring update for AB – Refer to the Live Map which reported extremely low numbers of moths intercepted so far (<45 province-wide as of 10Jun2021).
Cutworm reporting tool – Refer to the Live Map which reported four sites with cutworms (as of 10Jun2021).

Crop report links ( 2021 Week 6 )

Click the provincial name below to link to online crop reports produced by:
Manitoba Agriculture and Resource Development (subscribe to receive OR access a PDF copy of the June 8, 2021 report).
Saskatchewan Agriculture (or access a PDF copy of the June 1-7, 2021 report).
Alberta Agriculture and Forestry (or access a PDF copy of the June 1, 2021 report).

The following crop reports are also available:
• The United States Department of Agriculture (USDA) produces a Crop Progress Report (access a PDF copy of the June 7, 2021 edition).
• The USDA’s Weekly Weather and Crop Bulletin (access a PDF copy of the Jun 8, 2021 edition).

Previous posts ( 2021 Week 6 )

As the growing season progresses, the various Weekly Update topics move on and off the priority list for in-field scouting but they should be kept at hand to support season-long monitoring. Click to review these earlier 2021 Posts (organized alphabetically):
2020-2021 Risk and forecast maps
Crop protection guides (Wk03)
Cutworms (Wk02)
Flea beetles (Wk02)
Flea beetles – predicted geographic distribution and abundance (Wk04)
Ladybird beetles (Wk03)
Pea leaf weevil (Wk03)
Scouting charts – canola and flax (Wk03)
Slugs and their parasites (Wk04)
Wind trajectories for monitoring insect movement (Wk02)
Wireworms (Wk02)

Weekly Update ( 2021 Week 5 )

Week 5 and things are starting to heat up! Be sure to catch the Insect of the Week – it’s cereal leaf beetle! This week there’s more updated information coming your way and be sure to review the Previous Posts to keep all of the PPMN’s nsect monitoring resources at hand!

Stay safe and good scouting to you!

Questions or problems accessing the contents of this Weekly Update?  Please contact us so we can connect you to our information. Past “Weekly Updates” can be accessed on our Weekly Update page.

Weather synopsis ( 2021 Week 5 )

TEMPERATURE: This past week (May 24-30, 2021) the average temperature across the prairies was 1 °C cooler than normal (Fig. 1). Temperatures were warmest across most of Alberta and coolest across Saskatchewan and central regions of Manitoba. Across the prairies, the average 30-day (May 1-30) temperature was almost 2 °C warmer than last week and similar to climate normal values. Warmest temperatures were observed across southern Manitoba (Table 1; Fig. 2).

Figure 1. 7-day average temperature (°C) observed across the Canadian prairies for the period of May 24-30, 2021.
Figure 2. 30-day average temperature (°C) observed across the Canadian prairies for the period of May 1-30, 2021.

The 2021 growing season (April 1 – May 31) has been characterized by near-normal temperatures. Temperatures have been warmest for southern Manitoba, western Saskatchewan and southern Alberta (Table 2; Fig. 3).

Figure 3. Growing season average temperature (°C) observed across the Canadian prairies for the period of April 1-May 30, 2021.

The growing degree day map (GDD) (Base 5 ºC, April 1-May 31, 2021) is provided below (Fig. 4) while the growing degree day map (GDD) (Base 10 ºC, April 1-May 31, 2021) is shown in Figure 5.

Figure 4. Growing degree day map (Base 5 °C) observed across the Canadian prairies for the growing season (April 1-May 31, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (03Jun2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true
Figure 5. Growing degree day map (Base 10 °C) observed across the Canadian prairies for the growing season (April 1-May 31, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (03Jun2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

Several areas were on the receiving end of frost and many folks are still watching to see how their crops recover. The lowest temperatures recorded ranged from <-14 to >0 °C (Fig. 6) while the highest temperatures (°C) observed across the Canadian prairies the past seven days ranged from <11 to >25 °C (Fig. 7).

Figure 6. Lowest temperatures (°C) observed across the Canadian prairies the past seven days (May 27-Jun 2, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (03Jun2021) although PDF file format was not available. Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true
Figure 7. Highest temperatures (°C) observed across the Canadian prairies the past seven days (May 27-Jun 2, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (03Jun2021) although PDF file format was not available. Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

PRECIPITATION: This week, significant precipitation was reported across central regions of Saskatchewan and Alberta while minimal rain was reported across Manitoba and western Alberta (Fig. 8). Rainfall amounts for the period of May 1-30 (30-day accumulation) were 123 % of long-term average values. Rainfall amounts have been near normal to above normal for large areas of Alberta and southern Saskatchewan. Well above normal rain was reported for Edmonton and Regina. Below normal rainfall amounts were reported for central and northern areas of the Peace River region and across Manitoba (Table 1; Fig. 9).

Figure 8. 7-day cumulative rainfall (mm) observed across the Canadian prairies for the period of May 24-30, 2021.
Figure 9. 30-day cumulative rainfall (mm) observed across the Canadian prairies for the period of May 1-30, 2021.

Average growing season (April 1 – May 30) precipitation was 105 % of normal with the greatest precipitation occurring near Edmonton and across eastern Saskatchewan. Most of Manitoba and the Peace River region have had 60 % or less of normal precipitation during the 2021 growing season so far (Table 2; Fig. 10).

Figure x. Growing season cumulative rainfall (mm) observed across the Canadian prairies for the period of April 1-May 30, 2021.

The maps above are all produced by Agriculture and Agri-Food Canada. Growers can bookmark the AAFC Current Conditions Maps for the growing season. Historical weather data can be access at the AAFC Drought Watch Historical website, Environment Canada’s Historical Data website, or your provincial weather network.

Access ALL the PPMN’s Wind Trajectory reports (Weekly and Daily).

Access Environment and Climate Change Canada’s weather radar mapping interface. Options to access preceeding precipitation events include clicking off either an 1 or 3 hours time interval, using an 8-colour or 14-colour index. or changing the base map.

Weekly Wind Trajectory Report for June 3 ( 2021 Week 5 )

Access background information for how and why wind trajectories are monitored in this post.

1. REVERSE TRAJECTORIES (RT)
This past week there were an increasing number of reverse trajectories moving north from the Pacific Northwest (Idaho, Oregon and Washington) (Fig. 1). Though this US region can be a source of diamondback moths, the ECCC models predict air movement, not actual occurrence of diamondback moths.

Figure 1. The average number (based on a 5 day running average) of reverse trajectories that have crossed the prairies for the period of May 15 – June 3 2021.

a. Pacific Northwest (Idaho, Oregon, Washington) – This week there were 53 trajectories (compared to 36 last week) that crossed Alberta, Manitoba and Saskatchewan. In previous years, the majority of Pacific Northwest reverse trajectories usually have been reported to pass over southern Alberta. However, tis growing season, PNW trajectories have crossed all parts of the prairies (Figs. 2 and 3).

Figure 2. Total number of reverse trajectories originating across Idaho, Oregon, and Washington and have crossed specific prairie locations between March 18 and June 3, 2021.
Figure 3. Total number of dates with reverse trajectories originating over the Pacific Northwest (Idaho, Oregon, and Washington) and have crossed the prairies between March 24 and June 3, 2021.

b. Mexico and southwest USA (Texas, California) – Compared to previous years, there has been a noticeable increase in the number of trajectories from the southern US. The majority of these trajectories have crossed Manitoba and eastern Saskatchewan (Fig. 4). This week there were no trajectories (compared to 54 last week) that originated in Mexico or the southwest USA that crossed the prairies (Fig. 5).

Figure 4. Total number of reverse trajectories originating across Mexico, California and Texas and have crossed specific prairie locations between March 18 and June 3, 2021.
Figure 5. The total number of dates with reverse trajectories originating over Mexico, California and Texas and have crossed the prairies between March 24 and June 3, 2021.

c. Oklahoma and Texas – The majority of these trajectories have passed over Manitoba and eastern Saskatchewan (Fig. 6). This week there were no trajectories (compared to 51 last week) originating in Oklahoma or Texas that passed over the prairies (Fig. 7).

Figure 6. Total number of reverse trajectories originating across Oklahoma and Texas and have crossed specific prairie locations between March 18 and June 3, 2021.
Figure 7. The total number of dates with reverse trajectories originating over Oklahoma and Texas and have crossed the prairies between March 24 and June 3, 2021.

d. Kansas and Nebraska – Similar to results for Oklahoma and Texas, the majority of these trajectories crossed Manitoba and eastern Saskatchewan (Fig. 8). This week there was one trajectory that originated in Kansas or Nebraska that passed over Carman, Manitoba (Fig. 9). Relative to the reverse trajectories associated with Oklahoma and Texas, the trajectories from Kansas and Nebraska have crossed further into Alberta (Fig. 9).

Figure 8. Total number of reverse trajectories originating across Kansas and Nebraska and have crossed specific prairie locations between March 18 and June 3, 2021.
Figure 9. The total number of dates with reverse trajectories originating over Kansas and Nebraska and have crossed the prairies between March 24 and June 3, 2021.

2. FORWARD TRAJECTORIES (FT)
a. Continuing a trend that began last week, this week there was a decrease in the number of forward trajectories that were predicted to cross the prairies (Fig. 10). The dates on the graph report when the trajectories originated in the USA (blue bars). These trajectories generally require 3-5 days to enter the prairies (red line). The data suggests that, compared to this week, there will be decreased potential for the introduction of DBM to the prairies.

Figure 10. The average number (based on a 5-day running average) of forward trajectories that were predicted to cross the prairies for the period of May 15-June 3, 2021.

Alert: Bertha armyworm development ( 2021 Week 5 )

Model simulations to May 30, 2021, indicate that BAW pupal development is 45-60 % complete across the prairies (Fig. 1). Recent warm conditions in Alberta and southern Manitoba have resulted in the rapid development of BAW pupae (Fig. 2 C). The weather forecast for this week suggests that above-normal temperatures will occur. This could result in faster development of BAW pupae. BAW traps should be placed in fields when pupal development is approximately 80 %.

Figure 1. Predicted bertha armyworm (Mamestra configurata) pupal development across the Canadian prairies as of May 30, 2021.

IMPORTANT: Table 1 provides estimates for when the pheromone-baited green unitrap should be deployed. Based on weather conditions up to May 30, 2021, and model output, BAW adults (Fig. 2 D) may begin to emerge by mid to late June. Typically, moths emerge over an ~6 week period so cumulative counts of moths intercepted in these green unitraps provides insight into anticipated risk and prioritization for in-field scouting of the damaging larval stages later this summer.

Figure 2. The egg stage (A), larval stage (B), pupal stage (C), and adult stage (D) of bertha armyworm.
Photos: Jonathon Williams (AAFC-Saskatoon).

Model projections to June 30 predict that development near Regina (Fig. 3) will be more advanced than at Grande Prairie (Fig. 4). The model predicts that egg hatch will begin in late June near Regina.

Figure 3. Predicted development of bertha armyworm (Mamestra configurata) populations near Regina, Saskatchewan, as of May 30, 2021 (projected to June 30, 2021).
Figure 4. Predicted development of bertha armyworm (Mamestra configurata) populations near Grande Prairie, Alberta as of May 30, 2021 (projected to June 30, 2021).

Biological and monitoring information related to bertha armyworm in field crops is posted by the provinces of ManitobaSaskatchewanAlberta and the Prairie Pest Monitoring Network. Also, refer to the bertha armyworm pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is a free downloadable document as both an English-enhanced or French-enhanced version.

Predicted grasshopper development ( 2021 Week 5 )

The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

Model simulations were used to estimate grasshopper egg development as of May 30, 2021. Average development of eggs is 78 % and is well ahead of the long-term average of 67 %. Warm conditions across southeastern Saskatchewan and southern Manitoba (May 1-30) have been responsible for the advanced development of eggs near Regina, Saskatoon, Brandon and Winnipeg (Fig. 1). Egg development is predicted to exceed 80 % across most of the southern prairies (Fig. 2).

Figure 1. Predicted percent embryonic development of grasshopper eggs across the Canadian prairies as of May 30, 2021.
Figure 2. Predicted grasshopper (Melanoplus sanguinipes) embryological development (%) across the Canadian prairies as of May 30, 2021.

First hatchlings usually are observed once eggs reach 80 % development. As of May 30, hatch was predicted to be occurring across most of the prairies with hatch rates approaching 15-20 % across southern Manitoba and Saskatchewan (Fig. 3).

Figure 3. Predicted grasshopper (Melanoplus sanguinipes) hatch (%) across the Canadian prairies as of May 30, 2021.

The model was projected to June 15 to determine potential development at Saskatoon and Brandon over the next two weeks (Figs. 4 and 5). Results suggest that by June 15 hatch could be greater than 65 % at both locations and nymph populations will consist of first, second, and third instars. Drought conditions tend to favour the development of grasshopper populations while delaying crop development. If dry conditions persist, crop development may be delayed across Manitoba. This may result in conditions conducive to crop damage from grasshoppers as hatch progresses in June. Monitor roadsides and field margins to assess the development and densities of local grasshopper populations.

Figure 4. Predicted development of M. sanguinipes populations near Saskatoon, Saskatchewan as of May 30, 2021 (projected to June 15, 2021).
Figure 5. Predicted development of M. sanguinipes populations near Brandon, Manitoba as of May 30, 2021 (projected to June 15, 2021).

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture and Resource DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (accessible in either English-enhanced or French-enhanced versions).

Predicted cereal leaf beetle development ( 2021 Week 5 )

The cereal leaf beetle (CLB) model predicts that egg hatch is progressing across the prairies. The graphs provide a comparison of development at Lacombe (Fig. 1) and at Lethbridge (Fig. 2). The simulation indicates that second instar larvae will be observed over the next few days.

Figure 1. Predicted status of cereal leaf beetle (Oulema melanopus) populations near Lacombe, Alberta as of May 30, 2021 (projected to June 15, 2021).
Figure 2. Predicted status of cereal leaf beetle (Oulema melanopus) populations near Lethbridge, Alberta as of May 30, 2021 (projected to June 15, 2021).

Lifecycle and Damage:

Adult: Adult cereal leaf beetles (CLB) have shiny bluish-black wing covers (Fig. 3). The thorax and legs are light orange-brown. Females (4.9 to 5.5 mm) are slightly larger than males (4.4 to 5 mm). Adult beetles overwinter in and along the margins of grain fields in protected places such as in straw stubble, under crop and leaf litter, and in the crevices of tree bark. They favour sites adjacent to shelterbelts, deciduous and conifer forests. They emerge in the spring once temperatures reach 10-15 ºC and the adults are active for about 6 weeks. They usually begin feeding on grasses, then move into winter cereals and later into spring cereals.  

Figure 3. Adult Oulema melanopus measure 4.4-5.5 mm long (Photo: M. Dolinski).

Egg: Eggs are laid approximately 14 days following the emergence of the adults. Eggs are laid singly or in pairs along the midvein on the upper side of the leaf and are cylindrical, measuring 0.9 mm by 0.4 mm, and yellowish in colour. Eggs darken to black just before hatching.  

Larva: The larvae hatch in about 5 days and feed for about 3 weeks, passing through 4 growth stages (instars). The head and legs are brownish-black; the body is yellowish. Larvae are usually covered with a secretion of mucus and fecal material, giving them a shiny black, wet appearance (Fig. 4).  When the larva completes its growth, it drops to the ground and pupates in the soil. 

Figure 4.  Larval stage of Oulema melanopus with characteristic feeding damage visible on leaf (Photo: M. Dolinski).

Pupa: Pupal colour varies from a bright yellow when it is first formed, to the colour of the adult just before emergence. The pupal stage lasts 2 – 3 weeks. Adult beetles emerge and feed for a couple of weeks before seeking overwintering sites. There is one generation per year.

Fact sheets for CLB are published by the province of Alberta and available from the Prairie Pest Monitoring Network. Also access the Oulema melanopus page from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible in either English-enhanced or French-enhanced versions).

Predicted alfalfa weevil development ( 2021 Week 5 )

Model simulations for alfalfa weevil (AAW) predict, as of May 30, that egg hatch should be nearly complete across Manitoba and Saskatchewan. First instar larvae should be appearing across most of Manitoba (Fig. 1). The following graphs indicate that development is more advanced near Winnipeg (Fig. 2) than near Lethbridge (Fig. 3). This week, larval populations in southern Manitoba should be primarily in the second instar while populations in southern Alberta may consist of first instar larvae. Results suggest that by June 15, populations will be in the second and third larval instars across southern Alberta and that Manitoba populations will be in third and fourth instar stages.

Figure 1. Predicted development of Hypera postica (alfalfa weevil) populations across the prairies as of May 30, 2021.
Figure 2. Predicted status of alfalfa weevil (Hypera postica) development for populations near Winnipeg, Manitoba as of May 30, 2021 (projected to June 15, 2021).
Figure 3. Predicted status of alfalfa weevil (Hypera postica) development for populations near Lethbridge, Alberta as of May 30, 2021 (projected to June 15, 2021).

The larval stage of this weevil feeds on alfalfa leaves in a manner that characterizes the pest as a “skeletonizer” (Fig. 4).  The green larva features a dorsal white line down the length of its body, has a dark brown head capsule, and will grow to 9 mm long.  

Figure 4. Developmental stages of the alfalfa weevil (Hypera postica). Composite image: J. Soroka (AAFC-Saskatoon).

Alfalfa growers are encouraged to check the Alfalfa Weevil Fact Sheet prepared by Dr. Julie Soroka (AAFC-Saskatoon).  Additional information can be accessed by reviewing the Alfalfa Weevil Page extracted from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible in either English-enhanced or French-enhanced versions).

Field heroes ( 2021 Week 5 )

The Field Heroes campaign continues to raise awareness of the role of beneficial insects in western Canadian crops.

Two NEW Field Heroes resources for 2021 include:

  1. The NEW Pests and Predators Field Guide is filled with helpful images for quick insect identification and plenty of tips to manage the pests AND natural enemies in your fields. Claim your free copy at http://fieldheroes.ca/fieldguide/ or download for free to arm your in-field scouting efforts!
  2. Real Agriculture went live in 2021 with Season 2 of the Pest and Predators podcast series!
    NEWEpisode 10Good bugs relocate for work (June 1, 2021)
    Episode 9Secret agents in the stubble (May 18, 2021)
    Episode 8Good vs pea leaf weEVIL (May 4, 2021)
    Episode 7Powerful parasitoids: Better than fiction (April 20, 2021)
    Recap of SEASON 1: Episode 1 – Do you know your field heroes? Episode 2 – An inside look at the Prairie Pest Monitoring Network. Episode 3 – How much can one wasp save you? Episode 4 – Eat and be eaten — grasshoppers as pests and food Episode 5 – Killer wasp has only one target — wheat stem sawfly Episode 6 – Plentiful parasitoids

Access ALL the Field Heroes links here and be sure to follow @FieldHeroes!

Provincial insect pest report links ( 2021 Week 5 )

Provincial entomologists provide insect pest updates throughout the growing season so link to their information: 

MANITOBA’S Crop Pest Updates for 2021 are now available! Access the June 2, 2021, report here. Be sure to bookmark their Crop Pest Update Index to readily access these reports! Also bookmark their insect pest homepage to access fact sheets and more!

Bertha armyworm pheromone trap monitoring update for MB – Cooperators will soon deploy pheromone traps according to details provided on page 7 of the June 2, 2021, report.

Diamondback moth pheromone trap monitoring update for MB Refer to the summary updated twice a week. So far extremely low numbers have been intercepted in Manitoba. Read the details on page 7 of the June 2, 2021, report.

SASKATCHEWAN’S Crop Production News will soon be available. Access the new Crops Blog Posts and review Saskatchewan’s 2020 insect pest surveying results in order to prepare for 2021. Be sure to bookmark their insect pest homepage to access important information!

Bertha armyworm pheromone trap monitoring update for SK – Cooperators will soon deploy pheromone traps at sites across the province.

Diamondback moth pheromone trap monitoring update for SK – follow this link to find current DBM counts. At this point, extremely low numbers have been intercepted but monitoring continues. Seven moths were reported across the entire province so far (2021May19 Carter, pers. comm.).

•  ALBERTA’S Insect Pest Monitoring Network webpage links to insect survey maps, live feed maps, and insect trap set-up videos and more. There is also a Major Crops Insect webpage. The new webpage does not replace the Alberta Insect Pest Monitoring Network page. Remember, AAF’s Agri-News occasionally includes insect-related information or Twitter users can connect to #ABBugChat Wednesdays at 10:00 am.

Bertha armyworm pheromone trap monitoring update for AB – Cooperators will soon deploy pheromone traps so refer to the Live Map starting next week.

Diamondback moth pheromone trap monitoring update for AB – Refer to the Live Map which still reports extremely low numbers of moths intercepted so far (as of 03Jun2021).

Cutworm reporting tool for AB – Refer to the Live Map which reports three sites with cutworms (as of 03Jun2021).

Crop report links ( 2021 Week 5 )

Click the provincial name below to link to online crop reports produced by:
Manitoba Agriculture and Resource Development (subscribe to receive OR access a PDF copy of the June 1, 2021 report).
Saskatchewan Agriculture (or access a PDF copy of the May 25-31, 2021 report).
Alberta Agriculture and Forestry (or access a PDF copy of the May 25, 2021 report).

The following crop reports are also available:
• The United States Department of Agriculture (USDA) produces a Crop Progress Report (access a PDF copy of the June 1, 2021 edition).
• The USDA’s Weekly Weather and Crop Bulletin (access a PDF copy of the Jun 2, 2021 edition).

Previous posts ( 2021 Week 5 )

As the growing season progresses, the various Weekly Update topics move on and off the priority list for in-field scouting but they should be kept at hand to support season-long monitoring. Click to review these earlier 2021 Posts (organized alphabetically):
2020-2021 Risk and forecast maps
Crop protection guides (Wk03)
Cutworms (Wk02)
Flea beetles (Wk02)
Flea beetles – predicted geographic distribution and abundance (Wk04)
Ladybird beetles (Wk03)
Pea leaf weevil (Wk03)
Scouting charts – canola and flax (Wk03)
Slugs and their parasites (Wk04)
Wind trajectories for monitoring insect movement (Wk02)
Wireworms (Wk02)

Weekly Update ( 2021 Week 4 )

Week 4 and scouting continues despite the rain, some frost, and all those other crazy springtime things that affect agriculture! Be sure to catch the Insect of the Week – it’s pea leaf weevil! Click to review scouting information for cutworms, wireworms, pea leaf weevil, ladybird beetles, canola and flax scouting charts, Field Heroes, and the 2021 crop protection guides, plus there’s more updated information coming your way this week!

Stay safe and good scouting to you!

Questions or problems accessing the contents of this Weekly Update?  Please contact us so we can connect you to our information. Past “Weekly Updates” can be accessed on our Weekly Update page.

Weekly Wind Trajectory Report for May 28 ( 2021 Week 4 )

Access background information for how and why wind trajectories are monitored in this post.

1. REVERSE TRAJECTORIES (RT)
Since May 1, 2021 the majority of reverse trajectories that have crossed the prairies originated from the Pacific Northwest (Idaho, Oregon and Washington). For the past two weeks there have been an increasing number of reverse trajectories that moved north from Texas, Oklahoma, Kansas and Nebraska (Fig. 1). Compared to previous years, the number incoming trajectories (May) has increased. Though these US regions can be a source of diamondback moths, the ECCC models predict air movement, not actual occurrence of diamondback moths. It should also be noted that host plants of diamondback moth include all plants in the Brassicacea family, including cruciferous weeds and volunteer canola. These plants are suitable hosts until canola emerges.

Figure 1. The average number (based on a 5 day running average) of reverse trajectories that have crossed the prairies for
the period of May 1 – 27 2021.

a. Pacific Northwest (Idaho, Oregon, Washington) – This week there have been 36 trajectories (44 last week) that have crossed Alberta, Manitoba and Saskatchewan. In previous years, the majority of Pacific Northwest reverse trajectories usually have been reported to pass over southern Alberta. This growing season, PNW trajectories have crossed all parts of the prairies (Fig. 2). Compared to this time last year there has been a significant increase in the number of trajectories that have crossed Manitoba and eastern Saskatchewan.

Figure 2. Total number of dates with reverse trajectories originating over Pacific Northwest (Idaho, Oregon, and Washington) and
have crossed the prairies between March 24 and May 27, 2021.

b. Mexico and southwest USA (Texas, California) – Compared to previous years, there has been a noticeable increase in number of trajectories from the southern US. This week there have been 54 trajectories (15 last week) that originated in Mexico and the southwestern US that have crossed the prairies (Fig. 3).

Figure 3. The total number of dates with reverse trajectories originating over Mexico, California and Texas and have
crossed the prairies between March 24 and May 27, 2021.

c. Oklahoma and Texas – This week there have been 51 trajectories (16 last week) that have passed over Manitoba, Saskatchewan and eastern Alberta that originated in Oklahoma or Texas (Fig. 4).

Figure 4. The total number of dates with reverse trajectories originating over Oklahoma and Texas and have crossed
the prairies between March 24 and May 27, 2021.

d. Kansas and Nebraska – This week there have been 63 trajectories (35 last week) that originated in Kansas or Nebraska that have passed over the prairies (Fig. 5). Relative to the reverse trajectories associated with Oklahoma and Texas, the trajectories from Kansas and Nebraska have crossed further into Alberta.

Figure 5. The total number of dates with reverse trajectories originating over Kansas and Nebraska and have crossed
the prairies between March 24 and May 27, 2021.

2. FORWARD TRAJECTORIES (FT)
a. Forward trajectories, originating from Mexico and USA, have crossed a number of prairie locations since May 1, 2021. This week there has been a decrease in the number of trajectories that are predicted to cross the prairies (Fig. 6). The dates on the graph report when the trajectories originated in the USA (blue bars). These trajectories generally require 3-5 days to enter the prairies (red line). The data suggests that, compared to this week, there may be increased potential for the introduction of DBM to the prairies.

Figure 6. The average number (based on a 5-day running average) of forward trajectories that have crossed
the prairies for the period of May 1- 27, 2021.

Weather synopsis ( 2021 Week 4 )

TEMPERATURE: This past week (May 17-23, 2021) began with hot dry conditions followed by cool/wet conditions (mid-week reports of snow and minimum temperatures less than 0 °C). Most of the prairies had significant rainfall over the weekend. The average temperature across the prairies was 1 °C cooler than normal (Fig. 1). For the second week temperatures were warmest across Manitoba. Temperatures were coolest across western Saskatchewan and most of Alberta.

Figure 1. 7-day average temperature (°C) observed across the Canadian prairies for the period of May 17-23, 2021.

The prairie-wide average 30-day temperature (April 24- May 23) was 0.4 °C less than climate normal values. The warmest temperatures were observed across the southern prairies (Table 1; Fig. 2). The 2021 growing season (April 1 – May 16) has been characterized by near-normal temperatures. Temperatures have been similar across the prairies (Table 2; Fig. 3).

Figure 2. 30-day average temperature (°C) observed across the Canadian prairies for the period of April 24-May 23, 2021.
Figure 3. Growing season average temperature (°C) observed across the Canadian prairies for the period of April 1-May 23, 2021.

The growing degree day map (GDD) (Base 5 ºC, April 1-May 24, 2021) is provided below (Fig. 4) while the growing degree day map (GDD) (Base 10 ºC, April 1-May 24, 2021) is shown in Figure 5.

Figure 4. Growing degree day map (Base 5 °C) observed across the Canadian prairies for the growing season (April 1-May 24, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (27May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true
Figure 5. Growing degree day map (Base 10 °C) observed across the Canadian prairies for the growing season (April 1-May 24, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (27May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

Many were uttering the f-word this past week… several areas were on the receiving end of frost and many folks are still watching to see how their crops recover. The lowest temperatures recorded ranged from <-14 to >0 °C (Fig. 6) while the highest temperatures (°C) observed across the Canadian prairies the past seven days ranged from <11 to >25 °C (Fig. 7).

Figure 6. Lowest temperatures (°C) observed across the Canadian prairies the past seven days (May 20-26, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (27May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true
Figure 7. Highest temperatures (°C) observed across the Canadian prairies the past seven days (May 12-18, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (19May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

PRECIPITATION: This week average precipitation for the prairies was 17 mm (Fig. 8). Last week the average was less than 2 mm. Conditions continued to be dry in a large region bounded by Swift Current, Saskatoon and Vegreville as well as central and northern areas of the Peace River region. Rainfall amounts for the period of April 24-May 23 (30-day accumulation) were 88 % of long-term average values. Rainfall was greatest for large areas of Alberta, southern Saskatchewan and southern Manitoba (Table 1; Fig. 9). Average growing season (April 1 – May 23) precipitation was 86 % of normal (Table 1; Fig. 10). The map indicates that conditions continue to be very dry across the Peace River region, east-central Alberta, and west-central Saskatchewan.

Figure 8. 7-day cumulative rainfall (mm) observed across the Canadian prairies for the period of May 17-23, 2021.
Figure 9. 30-day cumulative rainfall (mm) observed across the Canadian prairies for the period of April 24-May 23, 2021.
Figure 10. Growing season cumulative rainfall (mm) observed across the Canadian prairies for the period of April 1-May 23, 2021.

The maps above are all produced by Agriculture and Agri-Food Canada. Growers can bookmark the AAFC Current Conditions Maps for the growing season. Historical weather data can be access at the AAFC Drought Watch Historical website, Environment Canada’s Historical Data website, or your provincial weather network.

Access ALL the PPMN’s Wind Trajectory reports (Weekly and Daily).

Access Environment and Climate Change Canada’s weather radar mapping interface. Options to access preceeding precipitation events include clicking off either an 1 or 3 hours time interval, using an 8-colour or 14-colour index. or changing the base map.

Flea beetles ( 2021 Week 4 )

Two species, Phyllotreta striolata and P. cruciferae, are the most chronic and economically important flea beetle pests of cruciferous crops in western Canada. Bioclimate simulation models for the two flea beetle species were developed to assess how climatic factors influence shifts in their geographic distribution and relative abundance. Economic risk was associated with populations in the orange and red zones (Figs. 1-4). It is crucial to note that the following information is NOT based on flea beetle densites BUT IS INSTEAD reflecting the suitability of environmental factors for P. striolata and P. cruciferae to prosper in highlighted areas of the following maps.

This spring has been approximately 1 °C cooler than normal. Recent rain (May 23-24) has resulted in precipitation amounts that are normal to above normal (30-day total) across Alberta and Saskatchewan. Simulations were run to determine how the two flea beetle species might respond to cooler, wetter conditions (compared to average growing seasons). Based on average temperature and precipitation (based on long term climate normals) risk associated with P. cruciferae is most prevalent across the southern prairies and risk related to P. striolata tends to be greatest across the Parkland and Peace River regions (Figs. 1 and 2).

Figure 1. Predicted risk for P. cruciferae, for model simulations based on long term climate normals. Red and orange regions may
be associated with economic crop losses.
Figure 2. Predicted risk for P. striolata, for model simulations based on long term climate normals. Red and orange regions may
be associated with economic crop losses.

For both species, cooler/wetter conditions generally could result in reduced risk and southward shifts in distribution (Figs. 3 and 4). Cooler and wetter than average growing seasons were predicted to have less negative impact on P. striolata than P. cruciferae. For example, Peace River populations of P. striolata are predicted to present reduced risk with cooler, wetter conditions (compared to average climate). Under similar conditions, P. cruciferae was predicted to have significantly reduced risk in the Peace River region. Wetter than average conditions in Manitoba may result in reduced risk from P. cruciferae and P. striolata. Olfert et al. (2017) reported that both species were more sensitive to temperature than moisture. Potential risk related to warmer temperatures was greater for P. cruciferae than P. striolata. Producers should monitor flea beetle species composition, crop stage and weather to assess potential flea beetle risk to cruciferous crops.

Figure 3. Predicted risk for P. cruciferae, for model simulations based on conditions that are cooler and wetter than current climate. Red and orange regions may be associated with economic crop losses.
Figure 4. Predicted risk for P. striolata, for model simulations based on conditions that are cooler and wetter than current climate. Red and orange regions may be associated with economic crop losses.

If flea beetle densities are high, seedling damage levels can advance quickly – even within the same day! The cotyledon stage of canola is vulnerable to flea beetle feeding. Review photos of flea beetle feeding damage posted earlier in the Weekly Update (Wk 02 – May 14, 2021) to help assess percent defoliated and to apply the action threshold of 25 % leaf area of cotyledons consumed plus flea beetles were the Insect of the Week (Wk 02 – May 10)!

Access biological and pest management information posted by Alberta Agriculture and Forestry, Saskatchewan Agriculture, or Manitoba Agriculture and Resource Development, or the Canola Council of Canada’s Canola Encyclopedia. Refer to the flea beetle page within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (Philip et al. 2018) as an English-enhanced or French-enhanced version.

Cereal leaf beetle development ( 2021 Week 4 )

The cereal leaf beetle (CLB) model output predicts that egg hatch may be starting across the prairies. The graphs provide a comparison of development at Saskatoon (Fig. 1) and at Lethbridge (Fig. 2). The simulation indicates that second instar larvae may occur during the last week of May near Saskatoon and Lethbridge.

Figure 1. Predicted status of cereal leaf beetle (Oulema melanopus) populations near Saskatoon, SK
as of May 23, 2021 (projected to June 7, 2021).
Figure 2. Predicted status of cereal leaf beetle (Oulema melanopus) populations near Lethbridge, AB
as of May 23, 2021 (projected to June 7, 2021).

Lifecycle and Damage:

Adult: Adult cereal leaf beetles (CLB) have shiny bluish-black wing covers (Fig. 3). The thorax and legs are light orange-brown. Females (4.9 to 5.5 mm) are slightly larger than males (4.4 to 5 mm). Adult beetles overwinter in and along the margins of grain fields in protected places such as in straw stubble, under crop and leaf litter, and in the crevices of tree bark. They favour sites adjacent to shelterbelts, deciduous and conifer forests. They emerge in the spring once temperatures reach 10-15 ºC and the adults are active for about 6 weeks. They usually begin feeding on grasses, then move into winter cereals and later into spring cereals.  

Figure 3. Adult Oulema melanopus measure 4.4-5.5 mm long (Photo: M. Dolinski).

Egg: Eggs are laid approximately 14 days following the emergence of the adults. Eggs are laid singly or in pairs along the midvein on the upper side of the leaf and are cylindrical, measuring 0.9 mm by 0.4 mm, and yellowish in colour. Eggs darken to black just before hatching.  

Larva: The larvae hatch in about 5 days and feed for about 3 weeks, passing through 4 growth stages (instars). The head and legs are brownish-black; the body is yellowish. Larvae are usually covered with a secretion of mucus and fecal material, giving them a shiny black, wet appearance (Fig. 4).  When the larva completes its growth, it drops to the ground and pupates in the soil. 

Figure 4.  Larval stage of Oulema melanopus with characteristic feeding damage visible on leaf (Photo: M. Dolinski).

Pupa: Pupal colour varies from a bright yellow when it is first formed, to the colour of the adult just before emergence. The pupal stage lasts 2 – 3 weeks. Adult beetles emerge and feed for a couple of weeks before seeking overwintering sites. There is one generation per year.

Fact sheets for CLB are published by the province of Alberta and available from the Prairie Pest Monitoring Network. Also access the Oulema melanopus page from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible in either English-enhanced or French-enhanced versions).

Alfalfa weevil predicted development ( 2021 Week 4 )

Model simulations for alfalfa weevil (AAW) predict that oviposition should be well underway across the prairies. The following graphs indicate that development is similar near Swift Current SK (Fig. 1) and Brandon MB (Fig. 2). The model predicts that that hatch may occur during the last week of May and that second instar larvae could be present during the first week of June.

Figure 1. Projected predicted status of alfalfa weevil (Hypera postica) populations near
Swift Current SK as of May 23, 2021 (projected to June 7, 2021).
Figure 2. Projected predicted status of alfalfa weevil (Hypera postica) populations near
Brandon MB as of May 23, 2021 (projected to June 7, 2021).

The larval stage of this weevil feeds on alfalfa leaves in a manner that characterizes the pest as a “skeletonizer” (Fig. 3).  The green larva featuring a dorsal, white line down the length of its body has a dark brown head capsule and will grow to 9 mm long.  

Figure 3. Developmental stages of the alfalfa weevil (Hypera postica). Composite image: J. Soroka (AAFC-Saskatoon).

Alfalfa growers are encouraged to check the Alfalfa Weevil Fact Sheet prepared by Dr. Julie Soroka (AAFC-Saskatoon).  Additional information can be accessed by reviewing the Alfalfa Weevil Page extracted from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible in either English-enhanced or French-enhanced versions).

Bertha armyworm development ( 2021 Week 4 )

Model simulations to May 23, 2021, indicate that overwintered BAW pupal development (Fig. 1, C) varies across the prairies. Development is predicted to be greatest across the southern prairies (Fig. 2). Based on current development, adult emergence is projected to occur in mid-June.

Figure 1. The egg stage (A), larval stage (B), pupal stage (C), and adult stage (D) of bertha armyworm.
Photos: Jonathon Williams (AAFC-Saskatoon).
Figure 2. Predicted bertha armyworm (Mamestra configurata) pupal development across the Canadian prairies as of May 23, 2021.

Biological and monitoring information related to bertha armyworm in field crops is posted by the provinces of ManitobaSaskatchewanAlberta and the Prairie Pest Monitoring Network. Also refer to the bertha armyworm pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is a free downloadable document as both an English-enhanced or French-enhanced version.

Predicted grasshopper development ( 2021 Week 4 )

The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

Model simulations were used to estimate grasshopper egg development as of May 23, 2021. Average development of eggs is 73 % and is well ahead of the long-term average of 62 %. Since last week, developmental rates increased at all locations. Recent warm conditions across southeastern Saskatchewan and southern Manitoba have been responsible for the advanced development of eggs near Regina, Brandon and Winnipeg (Fig. 1). The simulation predicted that development was greatest across most of the southern prairies (Fig. 2).

Figure 1. Predicted percent embryonic development of grasshopper eggs (Melanoplus sanguinipes) across
the Canadian prairies as of May 23, 2021.
Figure 2. Predicted grasshopper (Melanoplus sanguinipes) embryological development across the Canadian prairies as of May 23, 2021.

The model was projected to June 7 to determine potential development at Winnipeg and Lethbridge over the next two weeks (Figs. 3 and 4). Results suggest that by June 7 hatch could be at 20 % for Lethbridge and approximately 35 % near Winnipeg. Drought conditions tend to favour development of grasshopper populations while delaying crop development. If dry conditions persist, crop development may be delayed across Manitoba. This may result in conditions conducive to crop damage from grasshoppers as the hatch progresses in late May and early June.

Figure 3. Projected predicted development of M. sanguinipes populations near Winnipeg, Manitoba as of May 23, 2021 (projected to June 7, 2021).
Figure 4. Projected predicted development of M. sanguinipes populations near Lethbridge, Alberta as of May 23, 2021 (projected to June 7, 2021).

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture and Resource DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (accessible in either English-enhanced or French-enhanced versions).

Pestiferous slugs and their parasites ( 2021 Week 4 )

Researchers based at the University of Alberta are conducting a survey of pestiferous slugs and their associated nematode parasites from agricultural fields of Alberta. Last year, a peer-reviewed article was published (Nematology2020) which reported for the first time the presence of a parasitic nematode in Canada. The parasite can kill slugs and could have a role as a potential biocontrol agent against slug populations.

The slug survey continues this summer with researchers hoping to connect with producers who are interested in participating. If interested, please contact researchers at slugs@ualberta.ca now to participate by:
● Either allowing U of A staff to collect slugs from fields (1-2 times/month) or
● Arranging to send live slugs encountered in the field (please email first to obtain detailed collection instructions).

Email slugs@ualberta.ca to obtain more information.

Figure 1. Flag leaf feeding damage on wheat caused by the grey field slug (Deroceras reticulatum).
Photo taken near Crooked Creek AB on August 2, 2018, by J. Otani.

Provincial insect pest report links ( 2021 Week 4 )

Provincial entomologists provide insect pest updates throughout the growing season so link to their information: 

MANITOBA’S Crop Pest Updates for 2021 are now available! Access the May 26, 2021, report here. Be sure to bookmark their Crop Pest Update Index to readily access these reports! Also bookmark their insect pest homepage to access fact sheets and more!

Diamondback moth pheromone trap monitoring update for MB Refer to the summary updated twice a week. So far extremely low numbers have been intercepted in only sixteen traps (e.g., when present, only max. of 8 moths per site) in Manitoba. Read the details on page 5 of the May 26, 2021, report.

SASKATCHEWAN’S Crop Production News will soon be available. Access the new Crops Blog Posts and review Saskatchewan’s 2020 insect pest surveying results in order to prepare for 2021. Be sure to bookmark their insect pest homepage to access important information!

Diamondback moth pheromone trap monitoring update for SK – follow this link to find current DBM counts. At this point, extremely low numbers have been intercepted but monitoring continues. Seven moths were reported across the entire province so far (2021May19 Carter, pers. comm.).

•  ALBERTA’S Alberta Insect Pest Monitoring Network webpage links to insect survey maps, live feed maps, and insect trap set-up videos and more. Reminder – NEW for 2021 – AAF’s Shelley Barkley has gathered and streamlined information into a Major Crops Insect webpage. The new webpage does not replace the Alberta Insect Pest Monitoring Network page. However, the new Major Crops Insect webpage serves as a table of contents, connecting users to crop insect pest information on alberta.ca. It offers links to specific insect identification, life cycle, damage, monitoring and management. Users will hopefully find pertinent insect information with fewer clicks! Remember, AAF’s Agri-News occasionally includes insect-related information or Twitter users can connect to #ABBugChat Wednesdays at 10:00 am.

Diamondback moth pheromone trap monitoring update for AB – Refer to the Live Map which reports 12 sites, each with extremely low numbers, for a total of only 15 moths intercepted (as of 27May2021).

Cutworm reporting tool for AB – Refer to the Live Map which reports two sites with cutworms (as of 27May2021).

Crop report links ( 2021 Week 4 )

Click the provincial name below to link to online crop reports produced by:
Manitoba Agriculture and Resource Development (subscribe to receive OR access a PDF copy of the May 25, 2021 report).
Saskatchewan Agriculture (or access a PDF copy of the May 18-24, 2021 report).
Alberta Agriculture and Forestry (or access a PDF copy of the May 18, 2021 report).

The following crop reports are also available:
• The United States Department of Agriculture (USDA) produces a Crop Progress Report (access a PDF copy of the May 24, 2021 edition).
• The USDA’s Weekly Weather and Crop Bulletin (access a PDF copy of the May 25, 2021 edition).

Weekly Update ( 2021 Week 3 )

Week 3 and scouting continues for cutworms, flea beetles and wireworms plus there’s more information this week to help prepare for in-field scouting. Be sure to catch the Insect of the Week – it’s wireworms!

Now, more than ever, we wish everyone a safe and productive field season! Stay Safe!

Questions or problems accessing the contents of this Weekly Update?  Please contact us so we can connect you to our information. Past “Weekly Updates” can be accessed on our Weekly Update page.

Weather synopsis ( 2021 Week 3 )

TEMPERATURE: This past week the average temperature across the prairies was 2.5 °C warmer than normal (Fig. 1). Temperatures were warmest across the Parkland region in Manitoba, Saskatchewan, and Alberta.

Figure 1. 7-day average temperature (°C) observed across the Canadian prairies for the period of May 10-16, 2021.

The prairie-wide average 30-day temperature (April 17- May 16) was 0.9 °C less than climate normal values. A region from Winnipeg to Saskatoon has been 2 to 4 °C cooler than average. Temperatures have been warmest across southern Alberta (Table 1; Fig. 2).

Figure 2. 30-day average temperature (°C) observed across the Canadian prairies for the period of April 17-May 16, 2021.

The 2021 growing season (April 1 – May 16) has been characterized by near normal temperatures. Warmest temperatures were observed in a region between Lethbridge, Saskatoon and Edmonton while coolest temperatures were reported from Manitoba (Table 2; Fig. 3).

Figure 3. Growing season average temperature (°C) observed across the Canadian prairies for the period of April 1-May 16, 2021.

The growing degree day map (GDD) (Base 5 ºC, April 1-May 2, 2021) is provided below (Fig. 4) while the growing degree day map (GDD) (Base 10 ºC, April 1-August 9, 2020) is shown in Figure 5.

Figure 4. Growing degree day map (Base 5 °C) observed across the Canadian prairies for the growing season (April 1-May 17, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (19May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true
Figure 5. Growing degree day map (Base 10 °C) observed across the Canadian prairies for the growing season (April 1-May 17, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (19May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

At this early point in the growing season, cool temperatures pose the risk of frost but the differences between low and high temperatures can exert stress on plants, particularly when field conditions are dry. The lowest temperatures recorded ranged from <-8 to >6 °C (Fig. 6) while the highest temperatures (°C) observed across the Canadian prairies the past seven days ranged from <3 to >28 °C (Fig. 7).

Figure 6. Lowest temperatures (°C) observed across the Canadian prairies the past seven days (May 12-18, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (19May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true
Figure 7. Highest temperatures (°C) observed across the Canadian prairies the past seven days (May 12-18, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (19May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

PRECIPITATION: Seven-day cumulative rainfall amounts indicate that most of the prairies had less than 2 mm of rain in the past week (Fig. 8). Rainfall amounts for the period of April 17-May 16 (30-day accumulation) were 56 % of long-term average values. Rainfall was greatest for southwestern Saskatchewan and across most of Alberta (Table 1; Fig. 9).

Figure 8 . 7-day cumulative rainfall (mm) observed across the Canadian prairies for the period of May 10-16, 2021.
Figure 9. 30 day cumulative rainfall (mm) observed across the Canadian prairies for the period of April 17-May 16, 2021.

Average growing season (April 1 – May 16) precipitation has been well below average for most of the prairies (35 % less than normal). Saskatoon has reported 4.3 mm (15 % of normal) and most of Saskatchewan and Manitoba have had less than 15 mm (40 % of normal precipitation) (Table 1; Fig. 10).

Figure 10. Growing season cumulative rainfall (mm) observed across the Canadian prairies for the period of April 1-May 16, 2021.

The maps above are all produced by Agriculture and Agri-Food Canada. Growers can bookmark the AAFC Current Conditions Maps for the growing season. Historical weather data can be access at the AAFC Drought Watch Historical website, Environment Canada’s Historical Data website, or your provincial weather network.

Access ALL the PPMN’s Wind Trajectory reports (Weekly and Daily).

Access Environment and Climate Change Canada’s weather radar mapping interface. Options to access preceding precipitation events include clicking off either an 1 or 3 hours time interval, using an 8-colour or 14-colour index. or changing the base map.

Pea leaf weevil ( 2021 Week 3 )

The pea leaf weevil is a slender greyish-brown insect measuring approximately 5 mm in length (Fig. 1, Left image). Pea leaf weevil resembles the sweet clover weevil (Sitona cylindricollis) but the former is distinguished by three light-coloured stripes extending length-wise down thorax and sometimes the abdomen.  All species of Sitona, including the pea leaf weevil, have a short snout.  

Figure 1.  Comparison images and descriptions of four Sitona species adults including pea leaf weevil (AAFC-Otani).

Adults will feed upon the leaf margins and growing points of legume seedlings (alfalfa, clover, dry beans, faba beans, peas) and produce a characteristic, scalloped (notched) edge (Fig. 2).  Females lay their eggs in the soil either near or on developing pea or faba bean plants from May to June.

Figure 2. Examples of adult pea leaf weevil damage on field pea seedlings, (A) seedling with notches on all nodes, (B) stereotypical crescent shaped notches on the leaf margin, (C) clam or terminal leaf of the pea seedling with arrows indicating the feeding notches.
All photos courtesy of Dr. L. Dosdall.

Larvae develop under the soil and are “C” shaped and milky-white with a dark-brown head capsule ranging in length from 3.5-5.5 mm (Figure 3).  Larvae develop through five instar stages.  After hatching, larvae seek and enter the roots of a pea plant.  Larvae will enter and consume the contents of the nodules of the legume host plant. It is the nodules that are responsible for nitrogen-fixation which affect yield plus the plant’s ability to input nitrogen into the soil. Consumption of or damage to the nodules (Figure 4) results in partial or complete inhibition of nitrogen fixation by the plant and results in poor plant growth and low seed yields.

Figure 3. Larva of pea leaf weevil in soil (Photo: L. Dosdall).
Figure 4. Damaged pea nodules (Photo: L. Dosdall).

Biological and monitoring information related to pea leaf weevil in field crops is posted by the province of Alberta and in the PPMN monitoring protocol. Also access the Pea leaf weevil page from the Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and Management field guide. (en français : Guide d’identification des ravageurs des grandes cultures et des cultures fourragères et de leurs ennemis naturels et mesures de lutte applicables à l’Ouest canadien).

Cereal leaf beetle development ( 2021 Week 3 )

The cereal leaf beetle (CLB) model output predicts that oviposition is underway across the prairies. The graphs provide a comparison of development at Saskatoon (Fig. 1) and at Lacombe (Fig. 2). The simulation indicates that first instar larvae may occur during the third week of May near Saskatoon and one week later at Lacombe.

Figure 1. Predicted status of cereal leaf beetle populations near Saskatoon, SK as of May 16, 2021 (projected to May 31, 2021).
Figure 2. Predicted status of cereal leaf beetle populations near Lacombe, AB as of May 16, 2021 (projected to May 31, 2021).

Lifecycle and Damage:

Adult: Adult cereal leaf beetles (CLB) have shiny bluish-black wing covers (Fig. 3). The thorax and legs are light orange-brown. Females (4.9 to 5.5 mm) are slightly larger than males (4.4 to 5 mm). Adult beetles overwinter in and along the margins of grain fields in protected places such as in straw stubble, under crop and leaf litter, and in the crevices of tree bark. They favour sites adjacent to shelterbelts, deciduous and conifer forests. They emerge in the spring once temperatures reach 10-15 ºC and the adults are active for about 6 weeks. They usually begin feeding on grasses, then move into winter cereals and later into spring cereals.  

Figure 3. Adult Oulema melanopus measure 4.4-5.5 mm long (Photo: M. Dolinski).

Egg: Eggs are laid approximately 14 days following the emergence of the adults. Eggs are laid singly or in pairs along the midvein on the upper side of the leaf and are cylindrical, measuring 0.9 mm by 0.4 mm, and yellowish in colour. Eggs darken to black just before hatching.  

Larva: The larvae hatch in about 5 days and feed for about 3 weeks, passing through 4 growth stages (instars). The head and legs are brownish-black; the body is yellowish. Larvae are usually covered with a secretion of mucus and fecal material, giving them a shiny black, wet appearance (Fig. 4).  When the larva completes its growth, it drops to the ground and pupates in the soil. 

Figure 4.  Larval stage of Oulema melanopus with characteristic feeding damage visible on leaf (Photo: M. Dolinski).

Pupa: Pupal colour varies from a bright yellow when it is first formed, to the colour of the adult just before emergence. The pupal stage lasts 2 – 3 weeks. Adult beetles emerge and feed for a couple of weeks before seeking overwintering sites. There is one generation per year.

Fact sheets for CLB are published by the province of Alberta and available from the Prairie Pest Monitoring Network. Also access the Oulema melanopus page from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible in either English-enhanced or French-enhanced versions).

Alfalfa weevil predicted development ( 2021 Week 3 )

Model simulations for alfalfa weevil (AAW) predict that oviposition should be well underway across the prairies. The following graphs indicate that development is similar near Swift Current (Fig. 1) and Brandon (Fig. 2). The model predicts that that hatch may occur during the last week of May.

Figure 1. Projected predicted status of alfalfa weevil populations near Swift Current SK as of May 16, 2021 (projected to May 31, 2021).
Figure 2. Projected predicted status of alfalfa weevil populations near Brandon MB as of May 16, 2021 (projected to May 31, 2021).

Alfalfa growers are encouraged to check the Alfalfa Weevil Fact Sheet prepared by Dr. Julie Soroka (AAFC-Saskatoon).  Additional information can be accessed by reviewing the Alfalfa Weevil Page extracted from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible in either English-enhanced or French-enhanced versions).

Predicted grasshopper development ( 2021 Week 3 )

The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

Model simulations were used to estimate percent grasshopper egg development as of May 16, 2021. Average development of eggs is 68 % and is well ahead of the long term average of 59 %. Since last week, developmental rates have increased at all locations (Fig. 1). The simulation predicts that development is greatest in the region that includes Regina, Saskatoon and Lethbridge (Fig. 2).

Figure 1. Predicted percent embryonic development of grasshopper eggs across the Canadian prairies as of May 16, 2021.
Figure 2. Predicted grasshopper (Melanoplus sanguinipes) embryological development across the Canadian prairies as of May 16, 2021.

Recent warm temperatures near Winnipeg have resulted in faster development rates. The model was projected to May 31 to determine potential development at Saskatoon and Regina (Figs. 3 and 4). Results suggest that initial hatch may occur in the next few days with increased hatch occurring in late May. Current drought conditions tend to favour development of grasshopper populations while delaying crop development. Crop development may be delayed across southern and central regions of Saskatchewan. This may result in conditions conducive for crop damage from grasshoppers as hatch progresses in late May and early June.

Figure 3. Projected predicted development of M. sanguinipes populations near Regina SK as of May 16, 2021 (projected to May 31, 2021).
Figure 4. Projected predicted development of M. sanguinipes populations near Saskatoon SK as of May 16, 2021 (projected to May 31, 2021).

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture and Resource DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (accessible in either English-enhanced or French-enhanced versions).

Ladybird beetles ( 2021 Week 3 )

Early in the growing season many of the native and introduced species of ladybird beetles become active and are easily observed (Fig. 1). These adults give rise to a whole new legion of voracious larvae and adults so preserve and protect them in fields – it could pay off!

Figure 1. Ladybird beetle (Coleoptera: Coccinellidae) hunting on wheat head (photo: AAFC-Otani).

Coccinellids are recognized as general predators with a real taste for aphids. Many species exist in North America but introduced species (either released or adventively establishing on this continent) have displaced many native species. With such a fantastic array of colours, sizes, shapes, and spots, we’re providing a few resources to help you recognize the amazing diversity in fields:
● Access “Bug Guide” and their entries falling within the Family Coccinellidae.
● “Key to the lady beetles of Saskatchewan“, released by D.J. Larson in 2013 – a technical key that includes colour photos of ladybird beetle adults. Species included in this key will most closely resemble what’s present across the Canadian prairies.
● “Ladybugs of South Dakota” is a PDF visual example of several species of coccinellids, some of which will also occur on the Canadian prairies. The poster was produced in conjunction with the “Lost Ladybug Project” and other supporting institutions.
● Consider participating in citizen-science – the Lost Ladybug Project has been in place for many years but the group welcomes reports of coccinellids from anywhere in North America and helps identify from submitted photos. The goal is to keep track of native species in comparison to the helpful but fairly competitive introduced species like Coccinella semptempunctata or Harmonia axyridis (Pallas).
● The Canadian portal of iNaturalist.ca was launched in 2015 and is connected to iNaturalist.org but the premise is the same: By signing up and submitting photos with relevant brief observations (e.g., date, location, e-contact info), users can communicate online with creditable and knowledgeable resources that help identify flora and fauna. Watch their YouTube video to learn more. Download the App (Android Google Play OR iOS App Store).

FYI…. CABI’s Invasive Species Compendium entries contain more information about our most common introduced species of ladybird beetles in North America:
Coccinella septempunctata (seven-spot ladybird)
Harmonia axyridis (asian or harlequin ladybird)

Scouting charts for canola and flax ( 2021 Week 3 )

Reminder – Field scouting is critical – it enables the identification of potential risks to crops. Accurate identification of insect pests PLUS the application of established monitoring methods will enable growers to make informed pest management decisions.

We offer TWO generalized insect pest scouting charts to aid in-field scouting on the Canadian prairies:

1. CANOLA INSECT SCOUTING CHART (click chart to access downloadable PDF copy)

 2. FLAX INSECT SCOUTING CHART(click chart to access downloadable PDF copy)

These charts feature hyperlinks directing growers to downloadable PDF pages with photos within the “Field crop and forage pests and their natural enemies in western Canada: Identification and management field guide“.

Whenever possible, monitor and compare pest densities to established economic or action thresholds to protect and preserve pollinators and beneficial arthropods. Economic thresholds, by definition, help growers avoid crop losses related to outbreaking insect pest species.

Field heroes ( 2021 Week 3 )

The Field Heroes campaign continues to raise awareness of the role of beneficial insects in western Canadian crops. Check the recently updated Field Heroes website for scouting guides, downloadable posters, and videos. Learn about these important organisms at work in your fields!  

Two NEW Field Heroes resources for 2021 include:

  1. The NEW Pests and Predators Field Guide is filled with helpful images for quick insect identification and plenty of tips to manage the pests AND natural enemies in your fields. Claim your free copy at http://fieldheroes.ca/fieldguide/ or download for free to arm your in-field scouting efforts!
  2. Real Agriculture went live in 2021 with Season 2 of the Pest and Predators podcast series!
    NEWEpisode 10Good bugs relocate for work (June 1, 2021)
    Episode 9Secret agents in the stubble (May 18, 2021)
    Episode 8Good vs pea leaf weEVIL (May 4, 2021)
    Episode 7Powerful parasitoids: Better than fiction (April 20, 2021)
    Recap of SEASON 1: Episode 1 – Do you know your field heroes? Episode 2 – An inside look at the Prairie Pest Monitoring Network. Episode 3 – How much can one wasp save you? Episode 4 – Eat and be eaten — grasshoppers as pests and food Episode 5 – Killer wasp has only one target — wheat stem sawfly Episode 6 – Plentiful parasitoids

Access ALL the Field Heroes links here and be sure to follow @FieldHeroes!

Provincial insect pest report links ( 2021 Week 3 )

Provincial entomologists provide insect pest updates throughout the growing season so link to their information: 

MANITOBA’S Crop Pest Updates for 2021 are now available! Access the May 19, 2021, report here. Be sure to bookmark their Crop Pest Update Index to readily access these reports! Also bookmark their insect pest homepage to access fact sheets and more!

Diamondback moth pheromone trap monitoring update for MB Refer to the summary updated twice a week. So far extremely low numbers have been intercepted at only 8 sites (e.g., when present, only max. of 2 moths per site) in Manitoba. Read the details towards the end of the May 19, 2021, report.

SASKATCHEWAN’S Crop Production News will soon be available. Access the new Crops Blog Posts and review Saskatchewan’s 2020 insect pest surveying results in order to prepare for 2021. Be sure to bookmark their insect pest homepage to access important information!

Diamondback moth pheromone trap monitoring update for SK – follow this link to find current DBM counts. At this point, extremely low numbers have been intercepted but monitoring continues. Two moths were reported (2021May13 Tansey, pers. comm.); one moth near Shaunavon (RM78) and one moth near Raymore (RM 278).

•  ALBERTA’S Alberta Insect Pest Monitoring Network webpage links to insect survey maps, live feed maps, and insect trap set-up videos and more. Reminder – NEW for 2021 – AAF’s Shelley Barkley has gathered and streamlined information into a Major Crops Insect webpage. The new webpage does not replace the Alberta Insect Pest Monitoring Network page. However, the new Major Crops Insect webpage serves as a table of contents, connecting users to crop insect pest information on alberta.ca. It offers links to specific insect identification, life cycle, damage, monitoring and management. Users will hopefully find pertinent insect information with fewer clicks! Remember, AAF’s Agri-News occasionally includes insect-related information or Twitter users can connect to #ABBugChat Wednesdays at 10:00 am.

Diamondback moth pheromone trap monitoring update for AB – Refer to the Live Map which reports six sites with very low numbers of moths intercepted (as of 19May2021).

Cutworm reporting tool for AB – Refer to the Live Map which reports two sites with cutworms (as of 20May2021).

Crop report links ( 2021 Week 3 )

Click the provincial name below to link to online crop reports produced by:
Manitoba Agriculture and Resource Development (subscribe to receive OR access a PDF copy of the May 18, 2021 report).
Saskatchewan Agriculture (or access a PDF copy of the May 11-17, 2021 report).
Alberta Agriculture and Forestry (or access a PDF copy of the May 11, 2021 report).

The following crop reports are also available:
• The United States Department of Agriculture (USDA) produces a Crop Progress Report (access a PDF copy of the May 17, 2021 edition).
• The USDA’s Weekly Weather and Crop Bulletin (access a PDF copy of the May 18, 2021 edition).

ALERT – Wind Trajectory Report for May 19 ( 2021 Week 3 )

Access background information for how and why wind trajectories are monitored in this earlier post.

Alert: Yesterday and today ECCC models produced results that suggest a number of RT’s for prairie locations. Compared to previous dates, the ECCC model output predicts that trajectories are passing almost the entire prairie region over a very short period of time. The weather forecast may result in downward movement of DBM.

Details: There has been a significant increase in the number of trajectories, originating over a number of states in the USA, that have crossed the prairies (Fig. 1). These air currents may introduce diamondback moths to the prairies. ECCC trajectory models indicate that air trajectories, originating over the Pacific Northwest (Idaho, Oregon, Washington), have crossed Alberta, Saskatchewan and western Manitoba (Fig. 2). Trajectories originating over Texas and Oklahoma have passed over eastern Saskatchewan and Manitoba (Fig. 3). A third group of trajectories, originating across Kansas and Nebraska have also crossed eastern Saskatchewan and Manitoba (Fig. 4).

Though these US regions can be a source of diamondback moths, the ECCC models predict air movement, not actual occurrence of diamondback moths. It should also be noted that host plants of diamondback moth include all plants in the Brassicaceae family, including cruciferous weeds and volunteer canola. These plants are suitable hosts until canola emerges.

Action: The ECCC model output predicts that trajectories are passing almost the entire prairie region over a very short period of time. Areas highlighted in green in Figures 2, 3, and 4 of this alert may receive downward movement of DBM very shortly. The presence of any Brassicaceae plant will provide a host for incoming DBM so scout volunteers and emerging canola. If DBM were carried north on air currents it may take a few days for DBM to show up in traps.

Figure 1. Summary of the average number (5 day running average) of reverse trajectories that have crossed the Canadian prairies (May 1-19, 2021) 
Figure 2. The green region indicates the potential for introduction of diamondback moths from the Pacific Northwest (Idaho, Oregon, and Washington) to the Canadian prairies (May 18-19, 2021).
Figure 3. The green region indicates the potential for introduction of diamondback moths from Texas and Oklahoma to
the Canadian prairies (May 18-19, 2021).
Figure 4. The green region indicates the potential for introduction of diamondback moths from Kansas and Nebraska to the Canadian prairies (May 18-19, 2021).

Weekly Update ( 2021 Week 2 )

Week 2 and it’s time to get busy with in-field scouting for insects – cutworms, wireworms, flea beetles, and more are all active! In addition to the Weekly Update, be sure to catch the Insect of the Week.

Now, more than ever, we wish everyone a safe and productive field season! Stay Safe!

Questions or problems accessing the contents of this Weekly Update?  Please contact us so we can connect you to our information. Past “Weekly Updates” can be accessed on our Weekly Update page.

Weather synopsis ( 2021 Week 2 )

Since April 1, the 2021 growing season has been cooler and dryer than normal. The National Agroclimate Risk Report states that the most significant climate-related risk to agriculture is the dry conditions across the prairie region (access the Spring to April 27, 2021 report).

This past week (May 3-9, 2021), the average temperature across the prairies was 1.3 °C cooler than normal (Fig. 1). Similarly, the average 30-day temperature (April 10-May 9) was 1.7 °C less than climate normal values (Fig. 2). Temperatures have been warmest in southern Alberta (Table 1; Fig. 1-2).

Figure 1. Seven-day average temperature (°C) across the Canadian prairies for the period of May 3-9, 2021.
Figure 2. 30-day average temperature (°C) across the Canadian prairies for the period of April 10-May 9, 2021.

The growing degree day map (GDD) (Base 5 ºC, April 1-May 2, 2021) is provided below (Fig. 3) while the growing degree day map (GDD) (Base 10 ºC, April 1-August 9, 2020) is shown in Figure 4.

Figure 3. Growing degree day map (Base 5 °C) observed across the Canadian prairies for the growing season (April 1-May 11, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (12May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true
Figure 4. Growing degree day map (Base 10 °C) observed across the Canadian prairies for the growing season (April 1-May 11, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (12May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

At this early point in the growing season, cool temperatures pose the risk of frost but the differences between low and high temperatures can exert incredible stress on newly germinating plants in field crops. The lowest temperatures recorded ranged from <-59 to >-6 °C (Fig. 5) while the highest temperatures (°C) observed across the Canadian prairies the past seven days ranged from <11 to >26 °C (Fig. 6). Wow, what an amazing range – spring is tough!

Figure 5. Lowest temperatures (°C) observed across the Canadian prairies the past seven days (May 5-11, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (12May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true
Figure 6. Highest temperatures (°C) observed across the Canadian prairies the past seven days (May 5-11, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (12May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

Seven-day cumulative rainfall indicates that below normal rain (86% of average) was reported for the prairies (Fig. 7). Over the past seven-days rain totals across most of Alberta and the extreme southwest region of Saskatchewan was 10-20 mm. The rest of the prairies received little or no rain. Rain (30-day accumulation) amounts have been less than average for most of the prairies (81% of average). Rainfall for April 10-May 9, 2021, has been greatest for southeastern Manitoba, southwestern Saskatchewan and across most of Alberta (Table 1; Fig. 8). Average growing season (April 1 to May 9) precipitation has been well below average for most of the prairies. The two large regions (Swift Current to Prince Albert to Vegreville and the western two-thirds of Manitoba) have had less than 40 % of normal precipitation.

Figure 7. Seven-day cumulative rainfall (mm) observed across the Canadian prairies the past 30 days (May 3-9, 2021).
Figure 8. 30-day cumulative rainfall (mm) observed across the Canadian prairies the past 30 days (April 10-May 9, 2021).

The maps above are all produced by Agriculture and Agri-Food Canada. Growers can bookmark the AAFC Current Conditions Maps for the growing season. Historical weather data can be access at the AAFC Drought Watch Historical website, Environment Canada’s Historical Data website, or your provincial weather network.

Access ALL the PPMN’s Wind Trajectory reports (Weekly and Daily).

Access Environment and Climate Change Canada’s weather radar mapping interface.

Weekly Wind Trajectory Report (released May 13) ( 2021 Week 2 )

Agriculture and Agri-Food Canada (AAFC) and Environment and Climate Change Canada (ECCC) have been working together to study the potential of trajectories for monitoring insect movements since the late 1990s. Trajectory models are used to deliver an early-warning system for the origin and destination of migratory invasive species, such as diamondback moth. Read a brief overview of this strategy plus the definitions and applications of both ‘Reverse’ and ‘Forward’ trajectories.

1. REVERSE TRAJECTORIES (RT)
Since May 1, 2021, the majority of reverse trajectories crossing the prairies originated from the Pacific Northwest (Idaho, Oregon and Washington). This week, an increasing number of reverse trajectories have been moving north from Kansas and Nebraska (Fig. 1).

Figure 1. The average number (based on a 5-day running average) of reverse trajectories (RTs) that have
crossed the prairies for the period of May 1-13, 2021.

a. Pacific Northwest (Idaho, Oregon, Washington) – The majority of Pacific Northwest reverse trajectories have been reported to pass over southern Alberta (Fig. 2).

Figure 2. Total number of dates with reverse trajectories originating over the Pacific Northwest (PNW including Idaho, Oregon, and Washington) that have crossed the prairies between March 24 and May 13, 2021.

b. Mexico and southwest USA (Texas, California) – Since last week there have not been any trajectories that originated in these areas that have crossed the prairies.

c. Oklahoma and Texas – Since last week there have not been any trajectories originating in Oklahoma or Texas that have crossed the prairies.

d. Kansas and Nebraska – This week reverse trajectories were reported for Alberta (Andrew, Sedgewick), Saskatchewan (Gainsborough, Grenfell, Kindersley, Regina, Yorkton) and Manitoba (Brandon) (Fig. 3).

Figure 3. The total number of dates with reverse trajectories originating over Kansas and Nebraska that have crossed the
prairies between March 24 and May 13, 2021.

2. FORWARD TRAJECTORIES (FT)
Forward trajectories, originating from Mexico and USA have crossed a number of prairie locations since May 1, 2021. Based on average totals (averaged across a five day period), the greatest number of forward trajectories were observed to originate between May 5 and 8 (blue bars) and entered the prairies between May 6-9 (Fig. 4).

Figure 4. The average number (based on a 5 day running average) of forward trajectories that have crossed the
prairies for the period of May 1- 13, 2021.

The following map presents the total number of dates (since March 24, 2021) with forward trajectories that have crossed the Canadian prairies (Fig. 5). Results indicate that the greatest number of forward trajectories entering Canada originated from the Pacific Northwest (Idaho, Oregon, Washington).

Figure 5. The total number of dates with forward trajectories, originating from various regions of the United States and Mexico, that crossed the prairies between March 24 and May 13, 2021.

Access a PDF version of the full WEEKLY report released May13, 2021.

Cutworms ( 2021 Week 2 )

‘Tis the season…. to scout for cutworms! Scout fields that are “slow” to emerge, are missing rows, include wilting or yellowing plants, have bare patches, or appear highly attractive to birds – these are areas warranting a closer look.  Plan to follow-up by walking these areas later in the day when some cutworm species move above-ground to feed.  Start to dig below the soil surface (1-5 cm deep) near the base of a symptomatic plant or the adjacent healthy plant.  If the plant is well-established, check within the crown in addition to the adjacent soil.  The culprits could be wireworms, cutworms, or more!

Important: Several species of cutworms (Lepidoptera: Noctuidae) can be present in fields.  They range in colour from shiny opaque, to tan, to brownish-red with chevron patterning.  A field guide is available to help growers scout and manage the various species of cutworms that can appear in field crops grown on the Canadian prairies.  Cutworm Pest of Crops is available free in either English or French! Download a searchable PDF copy that includes great photos plus a table showing which larvae are active at different points in the growing season!

Other vital resources to scout and manage cutworms include:

For anyone on the Canadian prairies, Manitoba Agriculture and Rural Development’s Cutworms in Field Crops fact sheet includes action and economic thresholds for cutworms in several crops, important biological information, and great cutworm photos to support in-field scouting.

For Albertans….. If you find cutworms, please consider using the Alberta Insect Pest Monitoring Network’s “2021 Cutworm Reporting Tool” then view the live 2021 cutworm map which is updated daily. Review the live map to see where cutworms are appearing then prioritize in-field scouting accordingly.

Cutworms were featured as 2021’s first Insect of the Week. Follow the links to access IOTW’s descriptions of armydarksideddingyglassypale western and redbacked cutworms.

● The Prairie Pest Monitoring Network has cutworm biology, plant host range, and monitoring information available.

● The Canola Council of Canada’s Canola Encyclopedia also has cutworm information posted.

Wireworms ( 2021 Week 2 )

Newly seeded fields should be scouted throughout the germination and emergence periods for a variety of insect pests – one of the most difficult to detect can be wireworms! Wireworms are the juvenile stages of a complex comprised of several species of Elateridae, commonly referred to as ‘Click beetles’. On the Canadian prairies, wireworm collections from field crops indicate that three economically important species of wireworms or click beetles can be present; Selatosomus destructor, Limonius californicus, and Hypnoides bicolor. According to van Herk and Vernon (2014), a wide variety of Elateridae have been described from across the Canadian prairies; Alberta 144 species described in Alberta, 108 species described from Saskatchewan, and 109 species described from Manitoba.

Review these two wireworm posts to learn more and supplement in-field scouting:

Wireworms – Insect of the Week (2018)

Wireworm distribution map – Weekly Update (2018)

Biological and monitoring information related to wireworms in field crops is posted by Manitoba Agriculture and Resource Development, and Alberta Agriculture and Forestry. Also, refer to the wireworm pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (2018; accessible in either English-enhanced or French-enhanced versions).

Flea beetles ( 2021 Week 2 )

Newly emerging Brassicaceae but especially canola is attractive to overwintered flea beetles that emerge and become active early in the spring. As canola seedlings emerge, in-field scouting becomes crucial! If flea beetle densities are high, seedling damage levels can advance quickly – even within the same day! The cotyledon stage of canola is vulnerable to flea beetle feeding. Be sure to check out the Insect of the Week – Week 2 featured flea beetles!

Several species of flea beetles are present across North America. Be on the lookout for flea beetle damage resulting from feeding on canola cotyledons but also on the stem (Fig. 1).  Two species, Phyllotreta striolata (Fig. 1) and P. cruciferae, will feed on all cruciferous plants but they can cause economic levels of damage in canola during the seedling stages.

Figure 1. Flea beetle feeding damage (L) and striped flea beetle (R).

The Action Threshold for flea beetles on canola is 25% of cotyledon leaf area consumed.  Watch for shot-hole feeding in seedling canola but also watch the growing point and stems of seedlings which are particularly vulnerable to flea beetle feeding.

Estimating flea beetle feeding damage can be challenging.  Using a visual guide to estimate damage can be helpful.  Canola Watch circulated this article but also use the two images (Figs. 2 and 3; copied below for reference) produced by Dr. J. Soroka (AAFC-Saskatoon)  – take it scouting!

Figure 2. Canola cotyledons with various percentages of leaf area consume owing to flea beetle feeding damage (Photo: Soroka & Underwood, AAFC-Saskatoon).
Figure 3.  Percent leaf area consumed by flea beetles feeding on canola seedlings (Photo: Soroka & Underwood, AAFC-Saskatoon).

Access biological and pest management information posted by Alberta Agriculture and Forestry, Saskatchewan Agriculture, or Manitoba Agriculture and Resource Development, or the Canola Council of Canada’s Canola Encyclopedia. Refer to the flea beetle page within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (Philip et al. 2018) as an English-enhanced or French-enhanced version.

Two other favourite flea beetle resources relevant to field crop protection include:

Those armed with a stereomicroscope who are keen to monitor flea beetle species may wish to bookmark the “Common flea beetles of North Dakota” (Fauske 2003) which an excellent online resource and includes many of the commonly observed species of flea beetles also present across the Canadian prairies.

Soroka, J., Grenkow, L., Otani, J., Gavloski, J., & Olfert, O. (2018). Flea beetle (Coleoptera: Chrysomelidae) species in canola (Brassicaceae) on the northern Great Plains of North America. The Canadian Entomologist, 150(1), 100-115. doi:10.4039/tce.2017.60

Cereal leaf beetle development ( 2021 Week 2 )

The cereal leaf beetle (CLB) model output suggests that overwintered adults are active and that oviposition is underway across the prairies. The graphs provide a comparison of development for Saskatoon (Fig. 1) and Winnipeg (Fig. 2). The simulation indicates that first instar larvae may occur during the third week of May.

Figure 1. Predicted status of cereal leaf beetle populations near Saskatoon, SK as of May 9, 2021.
Figure 2. Predicted status of cereal leaf beetle populations near Winnipeg MB as of May 9, 2021.

Lifecycle and Damage:

Adult: Adult cereal leaf beetles (CLB) have shiny bluish-black wing covers (Fig. 3). The thorax and legs are light orange-brown. Females (4.9 to 5.5 mm) are slightly larger than males (4.4 to 5 mm). Adult beetles overwinter in and along the margins of grain fields in protected places such as in straw stubble, under crop and leaf litter, and in the crevices of tree bark. They favour sites adjacent to shelterbelts, deciduous and conifer forests. They emerge in the spring once temperatures reach 10-15 ºC and the adults are active for about 6 weeks. They usually begin feeding on grasses, then move into winter cereals and later into spring cereals.  

Figure 3. Adult Oulema melanopus measure 4.4-5.5 mm long (Photo: M. Dolinski).

Egg: Eggs are laid approximately 14 days following the emergence of the adults. Eggs are laid singly or in pairs along the midvein on the upper side of the leaf and are cylindrical, measuring 0.9 mm by 0.4 mm, and yellowish in colour. Eggs darken to black just before hatching.  

Larva: The larvae hatch in about 5 days and feed for about 3 weeks, passing through 4 growth stages (instars). The head and legs are brownish-black; the body is yellowish. Larvae are usually covered with a secretion of mucus and fecal material, giving them a shiny black, wet appearance (Fig. 4).  When the larva completes its growth, it drops to the ground and pupates in the soil. 

Figure 4.  Larval stage of Oulema melanopus with characteristic feeding damage visible on leaf (Photo: M. Dolinski).

Pupa: Pupal colour varies from a bright yellow when it is first formed, to the colour of the adult just before emergence. The pupal stage lasts 2 – 3 weeks. Adult beetles emerge and feed for a couple of weeks before seeking overwintering sites. There is one generation per year.

Fact sheets for CLB are published by the province of Alberta and available from the Prairie Pest Monitoring Network. Also access the Oulema melanopus page from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible in either English-enhanced or French-enhanced versions).

Predicted grasshopper development ( 2021 Week 2 )

The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

Model simulations were used to estimate percent grasshopper embryonic (egg) development as of May 9, 2021. The simulation predicts that development has now begun across southern areas of the Peace River region. Results indicate that egg development has been greatest for Lethbridge and Regina regions. Cool conditions in Manitoba have resulted in slower development rates (Figs. 1 and 2).

Figure 1. Predicted grasshopper (Melanoplus sanguinipes) embryological development across the Canadian prairies as of May 9, 2021. 
Figure 2. Predicted percent embryonic development of overwintered grasshopper eggs across the Canadian prairies as of May 9, 2021. 

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture and Resource DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (accessible in either English-enhanced or French-enhanced versions).

Alfalfa weevil predicted development ( 2021 Week 2 )

Model simulations for alfalfa weevil (AAW) indicate that oviposition should be well underway across the prairies. The following graphs indicate, based on potential number of eggs, that development is more advanced near Lethbridge (Fig. 1) than Brandon (Fig. 2). The model predicts that hatch may occur during the last week of May.

Figure 1. Projected predicted status of alfalfa weevil populations near Lethbridge AB as of May 9, 2021.
Figure 2. Projected predicted status of alfalfa weevil populations near Brandon MB as of May 9, 2021.

Alfalfa growers are encouraged to check the Alfalfa Weevil Fact Sheet prepared by Dr. Julie Soroka (AAFC-Saskatoon).  Additional information can be accessed by reviewing the Alfalfa Weevil Page extracted from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible in either English-enhanced or French-enhanced versions).

Provincial insect pest report links ( 2021 Week 2 )

Provincial entomologists provide insect pest updates throughout the growing season so link to their information: 

MANITOBA’S Crop Pest Updates for 2021 are now available! Access the May 12, 2021, report here. Be sure to bookmark their Crop Pest Update Index to readily access these reports!

Diamondback moth pheromone trap monitoring update for MB – So far (as of 12May2021). only one moth has been intercepted on a pheromone trap deployed near Austin.

SASKATCHEWAN’S Crop Production News will soon be available. Access the new Crops Blog Posts and review Saskatchewan’s 2020 insect pest surveying results in order to prepare for 2021. Be sure to bookmark their insect pest homepage to access important information!

Diamondback moth pheromone trap monitoring update for SK – two moths were reported (2021May13 Tansey, pers. comm.); one moth near Shaunavon (RM78) and one moth near Raymore (RM 278).

•  ALBERTA’S Alberta Insect Pest Monitoring Network webpage links to insect survey maps, live feed maps, and insect trap set-up videos and more. Additionally, NEW for 2021 – AAF’s Shelley Barkley has gathered and streamlined information into a Major Crops Insect webpage. The new webpage does not replace the Alberta Insect Pest Monitoring Network page. However, the new Major Crops Insect webpage serves as a table of contents, connecting users to crop insect pest information on alberta.ca. It offers links to specific insect identification, life cycle, damage, monitoring and management. Users will hopefully find pertinent insect information with fewer clicks! Remember, AAF’s Agri-News occasionally includes insect-related information or Twitter users can connect to #ABBugChat Wednesdays at 10:00 am.

Diamondback moth pheromone trap monitoring update for AB – Refer to the Live Map which reports zero moths (as of 13May2021).

Cutworm reporting tool for AB – Refer to the Live Map which reports two sites with cutworms (as of 13May2021).

Crop report links ( 2021 Week 2 )

Click the provincial name below to link to online crop reports produced by:

• Manitoba Agriculture and Resource Development – Subscribe to receive, or access a PDF copy of the May 12, 2021 report.

• Saskatchewan Agriculture  or access a PDF copy of the May 10, 2021 report.

• Alberta Agriculture and Forestry or access a PDF copy of the report released May 4, 2021.

The following crop reports are also available:

• The United States Department of Agriculture (USDA) produces a Crop Progress Report (read a PDF copy of the May 10, 2021 edition).

• The USDA’s Weekly Weather and Crop Bulletin (read a PDF copy of the May 11, 2021 edition). 

Wind Trajectory Report for May 10 ( 2021 Week 2 )

ECCC trajectory models indicate that air trajectories, originating over the Pacific Northwest (Idaho, Oregon, Washington), have crossed one Saskatchewan location (Unity) and a number of Alberta locations including Lethbridge, Beiseker, Olds, Provost, Vegreville, Andrew, Grande Prairie, Rycroft and Fort Vermillion.

Access this DAILY one-page report to learn more. Albertans and Saskatchewanians please take note!

Areas highlighted green in this alert may receive incoming winds from the Pacific Northwest of the USA very shortly! Remember, host plants of diamondback moth include all plants in the Brassicacea family, including cruciferous weeds and volunteer canola. These plants are suitable hosts until canola emerges. 

ALERT – Wind Trajectory Report for May 7 ( 2021 Week 1 )

Environment and Climate Change Canada (ECCC) trajectory models indicate that air trajectories, originating over the Pacific Northwest (Idaho, Oregon, Washington), have crossed a number of Alberta locations including Lethbridge, Beiseker, Olds, Manning, Rycroft, and Wanham.

Access this special one-page alert to learn more. Albertans please take note!

Action: Areas highlighted green in this alert may receive incoming winds from the Pacific Northwest of the USA very shortly so please deploy diamondback pheromone traps as soon as possible!

Weekly Update ( 2021 Week 1 )

Seeders are rolling across the prairies this week and we’re back for 2021 with Week 1! In addition to the Weekly Update, be sure to catch the Insect of the Week and Wind Trajectory Report.

Now, more than ever, we wish everyone a safe and productive field season! Stay Safe!

Questions or problems accessing the contents of this Weekly Update?  Please contact us so we can connect you to our information. Past “Weekly Updates” can be accessed on our Weekly Update page.

Weather synopsis ( 2021 Week 1 )

Since April 1, the 2021 growing season has been cooler and dryer than normal. This past week (April 26-May 2, 2021), the average temperature across the prairies was approximately 0.5 °C cooler than normal. Similarly, the average 30-day temperature (April 3- May 2) was 0.6 °C less than climate normal values. Temperatures have been warmest in southern Alberta. Seven day cumulative rainfall indicates that below normal rain (79% of average) was reported for the prairies.

Figure 1. 7-day average temperature (°C) across the Canadian prairies for the period of April 26-May 2, 2021.
Figure 2. 30-day average temperature (°C) across the Canadian prairies for the period of April 3-May 2, 2021.

The growing degree day map (GDD) (Base 5 ºC, April 1-May 2, 2021) is below (Fig. 3) while the growing degree day map (GDD) (Base 10 ºC, April 1-August 9, 2020) is shown in Figure 4.

Figure 3. Growing degree day map (Base 5 °C) observed across the Canadian prairies for the growing season (April 1-May 3, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (06May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true
Figure 4. Growing degree day map (Base 10 °C) observed across the Canadian prairies for the growing season (April 1-May 3, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (06May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

At this early point in the growing season, cool temperatures pose the risk of frost but the differences between low and high temperatures can exert incredible stress on newly germinating plants in field crops. The lowest temperatures ranged from <-14 to >0 °C (Fig. 5) while the highest temperatures (°C) observed across the Canadian prairies the past seven days ranged from <3 to >24 °C (Fig. 6).

Figure 5. Lowest temperatures (°C) observed across the Canadian prairies the past seven days (April 29-May 5, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (06May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true
Figure 6. Highest temperatures (°C) observed across the Canadian prairies the past seven days (April 29-May 5, 2021).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (06May2021). Access the full map at https://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

Rain (30-day accumulation) amounts have been less than average for most of the prairies (75 % of average; Fig. 7). Rainfall for April 3-May 2, 2021, has been greatest for southeastern Manitoba and the extreme southwest of Alberta (Fig. 8).

Figure 7. 30-day cumulative rainfall (mm) observed across the Canadian prairies the past 30 days (April 1-May 2, 2021).
Figure 8. Seven-day cumulative rainfall (mm) observed across the Canadian prairies the past 30 days (April 26-May 2, 2021).

The maps above are all produced by Agriculture and Agri-Food Canada. Growers can bookmark the AAFC Current Conditions Maps for the growing season. Historical weather data can be access at the AAFC Drought Watch Historical website, Environment Canada’s Historical Data website, or your provincial weather network.

Access the PPMN’s Weekly Wind Trajectory report released May 5, 2021.

FYI: Environment and Climate Change Canada updated the weather radar mapping interface recently.

Predicted grasshopper development ( 2021 Week 1 )

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

Model simulations were used to estimate percent grasshopper embryonic development as of May 2, 2021. Results indicate that egg development has begun across the southern prairies (Fig. 1) and progression estimates for sites across the prairies are presented in Figure 2.

Figure 1. Predicted grasshopper (Melanoplus sanguinipes) embryological development across the Canadian prairies as of May 2, 2021. 
Figure 2. Predicted percent embryonic development of overwintered grasshopper eggs across the Canadian prairies as of May 2, 2021. 

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture and Resource DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (accessible in either English-enhanced or French-enhanced versions).

Cereal leaf beetle development ( 2021 Week 1 )

The cereal leaf beetle (CLB) model output suggests that overwintered adults are active and that oviposition is underway across the prairies. The graphs provide a comparison of development for Lethbridge (Fig. 1) and Saskatoon (Fig. 2).

Figure 1. Predicted status of cereal leaf beetle populations near Lethbridge AB as of May 2, 2021.
Figure 2. Predicted status of cereal leaf beetle populations near Saskatoon SK as of May 2, 2021.

Lifecycle and Damage:

Adult: Adult cereal leaf beetles (CLB) have shiny bluish-black wing-covers (Fig. 3). The thorax and legs are light orange-brown. Females (4.9 to 5.5 mm) are slightly larger than males (4.4 to 5 mm). Adult beetles overwinter in and along the margins of grain fields in protected places such as in straw stubble, under crop and leaf litter, and in the crevices of tree bark. They favour sites adjacent to shelter belts, deciduous and conifer forests. They emerge in the spring once temperatures reach 10-15 ºC and the adults are active for about 6 weeks. They usually begin feeding on grasses, then move into winter cereals and later into spring cereals.  

Figure 3. Adult Oulema melanopus measure 4.4-5.5 mm long (Photo: M. Dolinski).

Egg: Eggs are laid approximately 14 days following the emergence of the adults. Eggs are laid singly or in pairs along the mid vein on the upper side of the leaf and are cylindrical, measuring 0.9 mm by 0.4 mm, and yellowish in colour. Eggs darken to black just before hatching.  

Larva: The larvae hatch in about 5 days and feed for about 3 weeks, passing through 4 growth stages (instars). The head and legs are brownish-black; the body is yellowish. Larvae are usually covered with a secretion of mucus and fecal material, giving them a shiny black, wet appearance (Fig. 4).  When the larva completes its growth, it drops to the ground and pupates in the soil. 

Figure 4.  Larval stage of Oulema melanopus with characteristic feeding damage visible on leaf (Photo: M. Dolinski).

Pupa: Pupal colour varies from a bright yellow when it is first formed, to the colour of the adult just before emergence. The pupal stage lasts 2 – 3 weeks. Adult beetles emerge and feed for a couple of weeks before seeking overwintering sites. There is one generation per year.

Fact sheets for CLB are published by the province of Alberta and available from the Prairie Pest Monitoring Network. Also access the Oulema melanopus page from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible in either English-enhanced or French-enhanced versions).

Alfalfa weevil predicted development ( 2021 Week 1 )

Models predicting the development of Alfalfa weevil (AAW) across the prairies are updated weekly to help growers time their in-field scouting for second-instar larvae. 

Model simulations for alfalfa weevil (AAW) indicate that oviposition should have begun across central and western areas of the prairies. The following graphs indicate, based on potential number of eggs, that development is more advanced near Regina SK (Fig. 1) than Winnipeg MB (Fig. 2).

Figure 1. Projected predicted status of alfalfa weevil populations near Regina SK as of May 2, 2021.
Figure 2. Projected predicted status of alfalfa weevil populations near Winnipeg MB as of May 2, 2021.

The larval stage of this weevil feeds on alfalfa leaves in a manner that characterizes the pest as a “skeletonizer”.  The green larva featuring a dorsal, white line down the length of its body has a dark brown head capsule and will grow to 9 mm long.  

Figure 3. Developmental stages of the alfalfa weevil (Hypera postica). Composite image: J. Soroka (AAFC-Saskatoon).

Alfalfa growers are encouraged to check the Alfalfa Weevil Fact Sheet prepared by Dr. Julie Soroka (AAFC-Saskatoon).  Additional information can be accessed by reviewing the Alfalfa Weevil Page extracted from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible in either English-enhanced or French-enhanced versions).

Field heroes ( 2021 Week 1 )

The Field Heroes campaign continues to raise awareness of the role of beneficial insects in western Canadian crops. Check the recently updated Field Heroes website for scouting guides, downloadable posters, and videos. Learn about these important organisms at work in your fields!  

Two important NEW resources for 2021 include:

  1. The NEW Pests and Predators Field Guide is filled with helpful images for quick insect indentification and plenty of tips to manage the pests AND natural enemies in your fields. Claim your free copy at http://fieldheroes.ca/fieldguide/ or download for free to arm your in-field scouting efforts!

2. Real Agriculture went live in 2021 with Season 2 of the Pest and Predators podcast series!

• Access Episode 6 – Powerful parasitoids: Better than fiction (April 20, 2021)

• Access Episode 7 – Good vs pea leaf weEVIL (May 4, 2021)

• Recap of SEASON 1: Episode 1 – Do you know your field heroes? Episode 2 – An inside look at the Prairie Pest Monitoring Network. 3 – How much can one wasp save you? Episode 4 – Eat and be eaten — grasshoppers as pests and food Episode 5 – Killer wasp has only one target — wheat stem sawfly Episode 6Plentiful parasitoids

Access ALL the Field Heroes links here and be sure to follow @FieldHeroes!

Provincial insect pest report links ( 2021 Week 1 )

Provincial entomologists provide insect pest updates throughout the growing season so link to their information: 

Manitoba‘s Crop Pest Updates for 2021 will soon become available. Be sure to bookmark their insect pest homepage to prepare for the season!

Saskatchewan‘s Crop Production News will soon be available. Access the new Crops Blog Posts and review Saskatchewan’s 2020 insect pest surveying results in order to prepare for 2021. Be sure to bookmark their insect pest homepage to access important information! Also, diamondback moth pheromone trap monitoring has begun in the province. To date, no moths have been intercepted (2021May06 Tansey, pers. comm.).

•  Alberta Agriculture and ForestryNEW for 2021 – AAF’s Shelley Barkley has gathered and streamlined information into a Major Crops Insect webpage. The new webpage does not replace the Alberta Insect Pest Monitoring Network page (where insect survey maps, live feed maps, and insect trap set-up videos can be found). However, the new Major Crops Insect webpage serves as a table of contents, connecting users to crop insect pest information on alberta.ca. It offers links to specific insect identification, life cycle, damage, monitoring and management. Users will hopefully find pertinent insect information with fewer clicks! Remember, AAF’s Agri-News occasionally includes insect-related information or Twitter users can connect to #ABBugChat Wednesdays at 10:00 am.

Crop report links ( 2021 Week 1 )


Click the provincial name below to link to online crop reports produced by:

• Manitoba Agriculture and Resource Development – Subscribe to receive, or access a PDF copy of the May 4, 2021 report.

• Saskatchewan Agriculture  or access a PDF copy of the May 3, 2021 report.

• Alberta Agriculture and Forestry or access a PDF copy of the report expected for public release on May 7, 2021.

The following crop reports are also available:

• The United States Department of Agriculture (USDA) produces a Crop Progress Report (read a PDF copy of the May 3, 2021 edition).

• The USDA’s Weekly Weather and Crop Bulletin (read a PDF copy of the May 4, 2021 edition). 

Good luck with harvest! ( 2020 Week 17 )

This is Week 17 and the last Weekly Update for 2020! It’s been an exceptional field season – responding to COVID-19 and a new website for the Prairie Pest Monitoring Network! Watch for special releases during the fall and winter. Your best option is to please subscribe to the new website to stay informed.

We thank the many people who have been monitoring, collecting, compiling and generating data throughout this growing season – your exceptional efforts are appreciated and critical! We also sincerely thank the many researchers, talented technical support staff, and the many students who have contributed to agricultural field crop protection, arthropod biodiversity, and insect pest management this season!

Questions or problems accessing the contents of the Weekly Update? Please email Meghan.Vankosky@canada.ca or Jennifer.Otani@canada.ca .

Weather synopsis ( 2020 Week 17 )

An abbreviated synopsis is provided for the final Weekly Update of the 2020 growing season. It was a warm week for most of the prairies! The highest temperatures the past seven days across the prairies are represented in Figure 1 and ranged from <22 to >35 °C.

Figure 1. Highest temperatures (°C) observed across the Canadian prairies the past seven days (April 1-August 19, 2020).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (20Aug2020). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209

All those high temperatures advanced the accumulation of heat units across the prairies. The growing degree day map (GDD) (Base 5 ºC, April 1-August 17, 2020) is below (Fig. 2) while the growing degree day map (GDD) (Base 10 ºC, April 1-August 17, 2020) is shown in Figure 3.

Figure 2. Growing degree day map (Base 5 °C) observed across the Canadian prairies for the growing season (April 1-August 17, 2020).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (20Aug2020). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209
Figure 3. Growing degree day map (Base 10 °C) observed across the Canadian prairies for the growing season (April 1-August 17, 2020).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (20Aug2020). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209

So far this growing season, the number of days above 25 °C ranges from 0-10 days in the northwest of the prairies then increases up to 61-70 days in southern Manitoba (Fig. 4). In comparison, the number of days above 30 °C ranges up to 25-27 days in southern Saskatchewan and southern Manitoba (Fig. 5)

Figure 4. Number of days above 25 °C observed across the Canadian prairies this growing season (April 1-August 19, 2020).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (20Aug2020). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209
Figure 5. Number of days above 30 °C observed across the Canadian prairies this growing season (April 1-August 19, 2020).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (20Aug2020). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209

As fields continue to mature in late August and in to September, growers will be watching for cool evenings. The lowest temperatures the past seven days across the prairies are represented in Figure 6 and ranged from <1 to >13 °C.

Figure 6. Lowest temperatures (°C) observed across the Canadian prairies the past seven days (April 1-August 19, 2020).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (20Aug2020). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209

Cumulative rainfall for the past 7 days was lowest across central and southern regions of Alberta and Saskatchewan while western and northern areas of the Peace River region AND eastern Saskatchewan plus much of Manitoba received more moisture (Fig. 7). Cumulative 30-day (Fig. 8) and rainfall for the growing season (April 1-August 19, 2020; Fig. 9) are below.

Figure 7. Observed cumulative precipitation across the Canadian prairies the past seven days (as of August 19, 2020).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (20Aug2020). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209
Figure 8. Observed cumulative precipitation across the Canadian prairies the past 30 days (as of August 19, 2020).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (20Aug2020). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209
Figure 9. Observed cumulative precipitation across the Canadian prairies for the growing season (as of August 19, 2020).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (20Aug2020). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209

The maps above are all produced by Agriculture and Agri-Food Canada. Growers can bookmark the AAFC Current Conditions Drought Watch Maps for the growing season. Historical weather data can be access at the AAFC Drought Watch website, Environment Canada’s Historical Data website, or your provincial weather network.