Wind trajectories

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.

The entire list of 2020 Wind Trajectory Reports is available here.

→ Read the WEEKLY Wind Trajectory Report for Wk10 (released June 22, 2020).

Weekly Update

Time to transition to more insects in field crops – add a few more to your scouting list!

Access information to support your in-field insect monitoring efforts in the complete Weekly Update either as a series of Posts for Week 9 OR a downloadable PDF.

Stay Safe!

Questions or problems accessing the contents of this Weekly Update? Please email Meghan.Vankosky@canada.ca or Jennifer.Otani@canada.ca. Past “Weekly Updates” can be accessed on our Weekly Update Blog Page.

Flax Pests / Feature Entomologist: Boyd Mori

This week’s Insect of the Week feature crop is flax, a crop that thrives in cooler environments. Our feature entomologist this week is Boyd Mori.

Flax Field
Ian Patterson cc by sa 2.0

Flax is a versatile crop grown across the Canadian Prairies, and is used in cooking, animal nutrition, and industrial production. Since 1994 Canada has been the largest flax producer and exporter in the world (Flax Council of Canada, 2020). In 2019 flax was grown on 375,700 hectares (928,500 acres) across the Prairies, producing 483,000 metric tonnes (532,400 US tons). Just under 80% of that total was grown in Saskatchewan.

Flax crops are susceptible to a number of pests. Monitoring and scouting protocols as well as economic thresholds (when available) are found in Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and Management and the Cutworm Pests of Crops on the Canadian Prairies: Identification and Management Field Guide. Additional monitoring protocols exist to control certain pests

Flax Pests:
  • Army cutworm
  • Aster leafhopper
  • Beet webworm
  • Bertha armyworm
  • Clover cutworm
  • Darksided cutworm
  • Dingy cutworm
  • Flax bollworm
  • Grasshoppers
  • Pale western cutworm
  • Potato aphid
  • Redbacked cutworm
Redbacked cutworm, larval stage – AAFC

Entomologist of the Week: Boyd Mori

Name: Boyd Mori
Affiliation: Department of Agricultural, Food and Nutritional Sciences, University of Alberta
Contact Information: bmori@ualberta.ca twitter: @BoydMori

How do you contribute in insect monitoring or surveillance on the Prairies? 

I actively participate in the PPMN. In my position at the U of A, I help monitor bertha armyworm and wheat midge at sites in North-Central Alberta.Next year, my research group will have a project that will try to verify the source of diamondback moths captured in pheromone traps. We will also be re-evaluating the wheat midge pheromone monitoring system with Dr. Maya Evenden (U of A). In the past, my former research group (AAFC-Saskatoon) along with Dr. Meghan Vankosky ran the survey for the canola flower midge in SK and MB and I occasionally helped with the pea leaf weevil survey in SK. I have also been involved with verifying some of the monitoring protocols used by all members of the PPMN.

In your opinion, what is the most interesting field crop pest on the Prairies?

Probably not a surprise to most, but I am going to have to say the canola flower midge, an insect I helped to recently discover and describe. The canola flower midge was previously mistaken for the swede midge, a significant pest of canola and other cruciferous vegetable crops in Ontario. Luckily, the canola flower midge is not as damaging as the swede midge (at least so far), and we are still trying to determine its overall pest status. What makes it really interesting is that we don’t know where the canola flower midge came from. We don’t know if it is a native or invasive species, although we tend to think it is native to the Prairies. We hypothesize it may have switched hosts to canola as acreage increased over the last 40 years, but we don’t know what is its original host plant was. There is a lot of interesting research to come on this species!

What is your favourite beneficial insect? 

I am partial to hover flies (Syrphids). The adult flies are often mistaken for bees due to their colouration, but they are harmless and actually help to pollinate many different plants. The larvae are active predators within crops, feeding on a variety of soft-bodied insects, especially aphids.

Tell us about an important project you are working on right now. 

I am currently working on a project with Dr. Hector Carcamo (AAFC-Lethbridge) and Jennifer Otani (AAFC-Beaverlodge) investigating insecticide resistance in alfalfa weevil in southern Alberta. We have identified a few populations with resistance to synthetic pyrethroids and we now have a graduate student, Michelle Reid, whose project will map resistance and also the presence of parasitoids throughout southern Alberta. We don’t see much insecticide resistance on the Prairies compared to other regions of the world, so this is a unique project.

What tools, platforms, etc. do you use to communicate with your stakeholders? 

I enjoy giving presentations, speaking with farmers and actively participating in extension events (e.g., CanolaPalooza, WheatStalk, Crop walks, etc.) and AGMs each year. Results of our work is published by industry magazines, blogs and newsletters. You can also reach me directly via email or Twitter (@BoydMori). Hopefully my research group will have a functional website soon too.

Weekly Update

Hello – again!

We had an email glitch so the Weekly Update was released over June 6-7, 2019.  

Please access the complete Weekly Update either as a series of Posts for Week 09 (June 6, 2019) OR a downloadable PDF.  Be sure to check out the Insect of the Week – the rest of the growing season features doppelgangers to aid in-field scouting!

Questions or problems accessing the contents of this Weekly Update?  Please e-mail either Dr. Meghan Vankosky or Jennifer Otani.  Past “Weekly Updates” can be accessed on our Weekly Update page.

Subscribe to the Blog by following these easy steps!

Weather synopsis

Weather synopsis – The prairie wide average temperature for May was 2 °C cooler than average (Fig. 1) while rainfall was approximately 50% of average (Fig. 2). The coolest conditions have occurred across southern MB and SK. 

Figure 1. Average temperature (°C) across the Canadian prairies for the month of May (May 1-31, 2019).
Figure 2. Mean temperature differences from Normal across the Canadian prairies from May 1-31, 2019.
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (06Jun2019).  Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

This week (May 29 – June 4, 2019) weather conditions were warm and dry. Across the prairies, temperatures were 3-4 °C warmer than last week and 1-2 °C warmer than average (Fig. 3). The warmest temperatures were observed across a region that extended from Medicine Hat AB to Saskatoon SK and southwestern MB.  

Figure 3. Average temperature (°C) across the Canadian prairies the past seven days (May 29-June 4, 2019).

Average 30-day temperatures were warmest in AB and coolest in eastern SK and MB (Fig. 4). Northern locations within the Peace River region were warmer than average. 

Figure 4. Average temperature (°C) across the Canadian prairies the past 30 days (May 5-June 4, 2019).

Seven day cumulative rainfall indicated that minimal rain was observed across most of the prairies (Fig. 5). Most locations reported less than 5 mm.  Higher rainfall amounts were reported in southwestern AB, southeastern SK and an area near Dauphin MB. 

Figure 5. Cumulative precipitation observed the past seven days across the Canadian prairies (May 29-June 4, 2019).

Across the prairies, rainfall amounts for the past 30 days (May 5 – June 4, 2019) were approximately 48 % of normal (Fig. 7 and 8). Most of the prairies reported rainfall amounts less than 40 % of normal. 

Figure 6. Cumulative precipitation observed the past 30 days across the Canadian prairies (May 5-June 4, 2019).

Growing season rainfall (April 1 – June 4) amounts have been well below average for most of the prairies, particularly in west central SK and eastern regions of AB (Fig. 7). Almost all of the prairies has had growing season rainfall that is 85 percent, or less, than average. 

Figure 7. Cumulative precipitation observed for the growing season across the Canadian prairies (April 1-June 4, 2019).
Figure 8. Percent of Average precipitation across the Canadian prairies for the growing season (April 1-June 5, 2019).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (06Jun2019).  Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

Soil moisture values are low across most of the prairies (Fig. 9). 

Figure 9. Modeled soil moisture (%) across the Canadian prairies (up to June 4, 2019).

The growing degree day map (GDD) (Base 5 ºC, April 1-June 3, 2019) is below (Fig. 10):

Figure 10. Growing degree day (Base 5 ºC) across the Canadian prairies for the growing season (April 1-June 3, 2019).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (06Jun2019).  Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

The growing degree day map (GDD) (Base 10 ºC, April 1-June 3, 2019) is below (Fig. 11):

Figure 11. Growing degree day (Base 10 ºC) across the Canadian prairies for the growing season (April 1-June 3, 2019).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (06Jun2019).  Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

The lowest temperatures (°C) observed the past seven days ranged from 6 to at least -5 °C in the map below (Fig. 12).

Figure 12. Lowest temperatures (°C) observed across the Canadian prairies the past seven days (May 30-June 5, 2019).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (06Jun2019).  Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

The highest temperatures (°C) observed the past seven days ranged from 14 to at least 32 °C in the map below (Fig. 14).

Figure 14. Highest temperatures (°C) observed across the Canadian prairies the past seven days (May 30-June 5, 2019).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (06Jun2019).  Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

The maps above are all produced by Agriculture and Agri-Food Canada.  Growers can bookmark the AAFC Drought Watch Maps for the growing season.

Predicted bertha armyworm development

Bertha armyworm (Lepidoptera: Mamestra configurata– Based on BAW model runs, pupal development is nearing 80% in some areas of southern and central AB and SK (Fig. 1). BAW adults may begin to emerge within the next 10 days (Table 1).It is advisable to place pheromone traps in fields when pupal development is 80% to capture the full extent of adult flight activity. Based on this value, traps should be put out in SK and AB fields this week.

Figure 1. Predicted bertha armyworm (Mamestra configurata) pupal development acrossthe Canadian prairies as of June 3, 2019. 
Table 1. Predicted emergence date of bertha armyworm moths at select locations across the Canadian prairies in 2019.

Recent warm conditions have advanced bertha armyworm (BAW) pupal development. Compared to last weekdevelopment is 2-6 days faster and development is 2 days ahead of normal (based on climate normals).  Model outputs were run for bertha armyworm for Saskatoon SK (Fig. 2), Lethbridge AB (Fig. 3), and Edmonton AB (Fig. 4).

Figure 2. Predicted development of bertha armyworm populations near Saskatoon SK as of June 3, 2019. 
Figure 3. Predicted development of bertha armyworm populations near Lethbridge AB as of June 3, 2019. 
Figure 4. Predicted development of bertha armyworm populations near Edmonton AB as of June 3, 2019. 

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 new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Cereal leaf beetle

Cereal leaf beetle (Oulema melanopus) – The cereal leaf beetle model indicates hatch has begun (Fig. 1).  Models were projected to June 21, 2019 and run for Lethbridge AB (Fig. 2), Grande Prairie AB (Fig. 3), and Brandon MB (Fig. 4). 

Figure 1.  Percent of populations of cereal leaf beetle (Oulema melanopus) in the larval stage as of June 3, 2019, across the Canadian prairies. 
Figure 2. Predicted status of cereal leaf beetle populations near Lethbridge AB projected to June 21, 2019, generated using long term average temperatures.
Figure 3. Predicted status of cereal leaf beetle populations near Grande Prairie AB projected to June 21, 2019, generated using long term average temperatures.
Figure 4. Predicted status of cereal leaf beetle populations near Brandon MB projected to June 21, 2019, generated using long term average temperatures.

Lifecycle and Damage:

Adult: Adult cereal leaf beetles (CLB) have shiny bluish-black wing-covers (Fig. 5). The thorax and legs are light orange-brown. Females (4.9 to 5.5 mm) are slightly larger than the 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 temperature reaches 10-15 ºC and are active for about 6 weeks. They usually begin feeding on grasses, then move into winter cereals and later into spring cereals.  

Figure 5. 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. 6).  When the larva completes its growth, it drops to the ground and pupates in the soil. 

Figure 6.  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 new “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide”.

Predicted grasshopper development

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).  

This week,  the grasshopper hatch is well underway across the prairies (Fig. 1 and 2) with most locations having approximately 15% hatch and some areas having 35% hatch. 

Figure 1. Predicted percent of grasshopper (Melanoplus sanguinipes) population at first instar stage across the Canadian prairies (as of June 4, 2019). 
Figure 2. Predicted percent of grasshopper (Melanoplus sanguinipes) population at second instar stage across the Canadian prairies (as of June 4, 2019). 

Model runs for Saskatoon SK (Fig. 3), Lethbridge AB (Fig. 4), and Grande Prairie AB (Fig. 5) were projected to June 30, 2019. Results for Lethbridge and Saskatoon indicated that populations are primarily in the first and second instars. A survey of roadsides south of Saskatoon indicated that melanoplines were primarily first an second instars. 

Figure 3. Predicted status of Melanoplus sanguinipes populations near Lethbridge  AB projected to June 30, 2019.  
Figure 4.  Predicted status of Melanoplus sanguinipes populations near Saskatoon SK projected to June 30, 2019.  
Figure 5.  Predicted status of Melanoplus sanguinipes populations near Grande Prairie AB projected to June 30, 2019.  

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

Alfalfa weevil

Alfalfa Weevil (Hypera postica) – Degree-day maps of base 9°C are produced using the Harcourt/North Dakota models (Soroka et al. 2015).  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. 

Weather conditions continue to be favourable for development of alfalfa weevil, if alfalfa weevil are present in your area. First instar development is nearing completion (Fig. 1) and the more individuals in the population should be in the second instar stage (Fig. 2). 

Figure 1. Percent of populations of alfalfa weevil (Hypera postica)  in the first instar stage across the Canadian prairies as of June 3, 2019. 
Figure 2. Percent of populations of alfalfa weevil (Hypera postica)  in the second instar stage across the Canadian prairies as of June 3, 2019.

Model runs for Brooks AB (Fig. 3)  and Swift Current SK (Fig. 4) were projected to June 21, 2019.  In alfalfa fields near Brooks AB larvae should start to reach the third instar stage late this week. At Swift Current SK third instar larvae will begin to appear approximately 5-7 days later.

Figure 3. Predicted status of alfalfa weevil populations near Brooks AB projected to June 21, 2019using long term average temperatures.
Figure 4. Predicted status of alfalfa weevil populations near Swift Current SK projected to June 21, 2019using long term average temperatures.

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 9mm long.  

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” (Philip et al. 2015). The guide is available in both a free English-enhanced or French-enhanced version.

Pea leaf weevil

Pea Leaf Weevil (Sitona lineatus– Model runs for Red Deer and Saskatoon were projected to June 30, 2019. Results indicated that oviposition is well underway at both locations.  

Figure 1. Predicted status of pea leaf weevil populations near Red Deer AB projected to June 30, 2019, using long term average temperatures.
Figure 2.  Predicted status of pea leaf weevil populations near Saskatoon SK projected to June 30, 2019, using long term average temperatures.

This week, pea leaf weevil and its doppelgangers were featured as part of the INSECT OF THE WEEK.  

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.  Females lay 1000 to 1500 eggs in the soil either near or on developing pea or faba bean plants from May to June.

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 refer to the pea leaf weevil page within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.  A review of this insect was published in 2011 in Prairie Soils and Crops by Carcamo and Vankosky.

Cereal Aphid Manager (CAM)

Congratulations!  The Cereal Aphid Management (CAM) Mobile Application Team was recognized with an Agriculture and Agri-Food Canada Gold Harvest Award this month!  Team members included Ashraf Eid, Paul Faure, John Gavloski, François Jodoin, Elham Karimi, Eric Li, Jackson Macdonald, Nancy MacDonald, Owen Olfert, Chrystel Y. Olivier, 

Daniel Shen, Erl Svendsen, Gabriel Tobian, Tyler J. Wist.

“The app is a culmination of innovative thinking, extensive research, and most importantly collaboration in order to design a tool that met the needs of the farming community. The team’s ability to work together and build this application will result in economic savings, a greener environment, and increased crop quality in the food production industry.”

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) innovative 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.

By taking into consideration factors like these, the app predicts what the aphid population will be in seven days and the best time to apply insecticide based on economic thresholds.

Available in iOS and Android.

To learn more and to download, go to AAFC’s CAM webpage.

Note: Cereal aphids can blow up from the South at any time which cannot be predicted by the app. Therefore, farmers and crop advisors should regularly check fields during the growing season regardless of what Cereal Aphid Manager Mobile may recommend.

CAM Homepage
CAM monitoring report and recommendation
CAM icon

Field Events – Speak to an entomologist

Public summer field events – Coming to a field near you –  Prairie field crop entomologists are already scheduled to be at these 2019 field tour events from May-August (be sure to re-confirm dates and details as events are finalized):

•  June 20, 2019: Solstice Forage and Crops Field Tour to be held at the Beaverlodge Research Farm (Beaverlodge AB).  View event info/registration details.  Entomologists tentatively participating: Jennifer Otani, Keith Uloth

•  June 26, 2019: 2019 CanolaPALOOZA to be held at the Lacombe Research and Development Centre (Lacombe AB).  View event info/registration details.  Entomologists tentatively participating: Jennifer Otani, Amanda Jorgensen, Meghan Vankosky, Scott Meers, Shelley Barkley, Patty Reid, Sunil Shivananjappa, Hector Carcamo, Julie Soroka, Mark Cutts, Jim Tansey, Sherrie Benson and the Junior Entomologists.

•  July 9-12, July 16-18, 2019: Crop Diagnostic School. Held at the University of Manitoba Research Farm at Carman, Manitoba. An 2-week diagnostic school will complete units on entomology, plant pathology, weed science, soil fertility, pulse crop production, and oilseed production. View registration and event information. Entomologists participating: John Gavloski and Jordan Bannerman.

•  July 9, 2019: CanolaPALOOZA Saskatoon, to be held at the SRDC Llewellyn Farm. Read more about this event.  Entomologists presenting: Tyler Wist, James Tansey, Greg Sekulic, Meghan Vankosky

•  July 22, 2019: Pulse grower gathering held near Three Hills AB.  Check Alberta Pulse Growers Event Page for more information.  Entomologists presenting: Graduate students from Dr. Maya Evenden’s (U of A) working on pea leaf weevil.

•  July 23-24, 2019: Crop Diagnostic School, Scott Saskatchewan. Read more about this event.  Entomologists presenting: Meghan Vankosky, Tyler Wist.

•  July 24, 2019: Crops-a-Palooza. Held at Canada-Manitoba Crop Diversification Centre (CMCDC), Carberry, Manitoba. Read more about this event. Entomologist participating: John Gavloski, Vincent Hervet, Tharshi Nagalingam, Bryan Cassone.

•  August 8, 2019:  2019 Wheatstalk to be held at Teepee Creek AB.  View event info/registration details.   Entomologists tentatively participating: Jennifer Otani, Amanda Jorgensen, Boyd Mori.

  August 8, 2019. Horticulture School. Agriculture and Agri-Food Canada Research Farm, Portage la Prairie, Manitoba. Entomologist presenting: John Gavloski, Kyle Bobiwash.

Provincial Insect Pest Reports

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

Manitoba‘s Insect and Disease Updates for 2019 are posted here and includes an update posted June 5, 2019.

Saskatchewan‘s Crops Blog Posts includes a segment on “Early season scouting of cutworms” by Sara Doerksen posted in April 2019 and “Economic thresholds” by Kaeley Kindrachuk posted in May 2019.

•  Alberta Agriculture and Forestry’s Call of the Land regularly includes insect pest updates from Mr. Scott Meers. The most recent Call of the Land was posted March 18-22, 2019 but did not include an insect update.

Crop report links

Crop reports are produced by:
• Manitoba Agriculture (June 4, 2019 or access the current online report)
• Saskatchewan Agriculture (May 28-June 3, 2019) or access the current online report).
• Alberta Agriculture and Forestry Crop Report (May 28, 2019 or access the current online report)

The following crop reports are also available:
• The United States Department of Agriculture (USDA) produces a Crop Progress Report (read the June 3, 2019 edition).

• The USDA’s Weekly Weather and Crop Bulletin (read the June 4, 2019 edition). 

Monarch migration

We continue to track the migration of the Monarch butterflies as they move north by checking the 2019 Monarch Migration Map!  A screen shot of the map has been placed below as an example (retrieved 06Jun2019) but follow the hyperlink to check the interactive map.  They are in Manitoba!

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.  

Previous Posts

Click to review these earlier 2019 Posts:

2019 Risk and forecast maps – Week 2

Crop protection guides – Week 6
Cutworms – Week 5

Field heroes – Week 6
Flea beetles – Week 5

Insect scouting chart for Canola – Week 5
Insect scouting chart for Flax – Week 5

Painted lady butterfly – Week 8

Ticks and Lyme disease – Week 4

Weather Radar – Week 6
Wildfires – Week 8

Wind trajectories – Weeks 1-4

Insect of the Week – Doppelgangers: Pea leaf weevil and other Sitona species

The case of the innocuous versus the evil twin: When making pest management decisions, be sure that the suspect is a actually a pest. This can be challenge since insects often mimic each other or look very similar. An insect that looks, moves and acts like a pest may in fact be a look-alike or doppelganger. 

Doppelgangers may be related (e.g. same genus) or may not be related, as in the case monarch butterflies (Danaus plexippus) and viceroys (Limenitis achrippus).  In some cases, doppelgangers are relatively harmless. In others, the doppelganger is a pest too yet behaviour, lifecycle and hosts may be different. 

Correctly identifying a pest enables selection of the most accurate scouting or monitoring protocol. Identification and monitoring enables the application of economic thresholds. It also enables a producer to select and apply the most effective control option(s) including method and timing of application.  For the rest of the growing season, the Insect of the Week will feature insect crop pests and their doppelgangers.

The case of the pea weevil and other Sitona species doppelgangers

Weevils of the genus Sitona are broad-nosed weevils that are pests of various legume crops, including field pea, faba bean, alfalfa and sweet clover. Sitona larvae attack the roots of the host plant and usually consume the root nodules and the enclosed symbiotic bacteria that fix nitrogen. Adult Sitona weevils consume plant leaves resulting in ‘U’-shaped feeding notches. Sitona species  known to occur in Canada include:

• Sitona lineatus –  pea leaf weevil (Fig. 1), has two primary hosts: field pea and faba bean.
• Sitona cylindricollis – clover root weevil or sweet clover weevil (Fig. 4).
Sitona hispidulus – clover root curculio* (Fig. 3), a clover pest.
Sitona lineellus –  alfalfa curculio (Fig. 5), eats alfalfa, vetch and field pea.
Sitona obsoletus (=S. flavescens = S. lepidus) – clover root curculio*, a clover pest (Fig. 6).

Note that common names can be used to describe more than one species and can be confusing.

Figure 1. Pea leaf weevil (Sitona lineatus L.).
Photo: AAFC-Sasktoon-Williams.

The above five Sitona species found in Canada are doppelgangers of each other for several reasons:

1. Similar in size and appearance – Require a taxonomic key and microscope to accurately identify to species. Notable difference is Sitona hispidulus which has hairy elytra compared to the other four species which lack hair on their elytra (Fig. 2). 

2.  Sitona weevils share primary and secondary hosts – Pea leaf weevils must feed on primary hosts (i.e., field pea and faba bean) to attain sexual maturation AND the larvae must feed on primary hosts to successfully develop. However, early in the spring and again in the fall, pea leaf weevils feed on virtually any species of legume, including the primary host plants of the other four Sitona species.

3. Foliar feeding damage is similar – According to Weich and Clements (1992), “careful scrutiny” is required to differentiate the feeding damage caused by different Sitona species feeding on the same host plant. Therefore, it is important to collect adult weevils for identification to confirm which species is responsible for foliar damage.

Figure 2. Characteristics of four of the five Sitona species found in Canada, useful when scouting for pea leaf weevils. See  also the pea leaf weevil monitoring protocol. Images © AAFC-Beaverlodge

Species pages for all five species available by searching the species names in the E.H. Strickland Entomology Museum: http://www.entomology.museums.ualberta.ca/searching.php

Figure 3. Clover root curculio (Sitona hispicula Fabricious).
Photo: © Donald Hobern  
Figure 5.  Alfalfa curculio (Sitona lineellus Bonsdorff). 
Photo: © by nc Chris Moody.
Figure 4.  Sweet clover weevil (Sitona cylindricollis Fahreaus). Photo: © Janet Graham.
Figure 6.  Clover root curculio (Sitona obsoletus).
Photo: by K. Walker

More information about pea leaf weevil (Sitona lineatus), and sweetclover weevil (Sitona cylindricollis) can be accessed on the Insect of the Week page. Information related to crop pests and their natural enemies can be found in the newly updated Field Guide and Cutworm Guide. Both are available for free download on our Insect Field Guide and Cutworm Field Guide pages.

Meghan Vankosky (@DrVanbugsky)

Wind Trajectories

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.

In a continuing effort to produce timely information, the wind trajectory reports are available in two forms:

Prairie Crop Disease Monitoring Network

The Prairie Crop Disease Monitoring Network (PCDMN) represents the combined effort of our prairie pathologists who work together to support in-field disease management in field crops.  

In 2019, the PCDMN will release a series of weekly Cereal Rust Risk Reports throughout May and June.  Information related to trajectory events based on forecast and diagnostic wind fields and cereal rust risk is experimental, and is OFFERED TO THE PUBLIC FOR INFORMATIONAL PURPOSES ONLY. 

Background:  Agriculture and AgriFood 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. In addition, plant pathologists have shown that trajectories can assist with the prediction of plant disease infestations and are also beginning to utilize these same data. An introduction will be presented of efforts to identify wind trajectory events that may bring rust urediniospores into Western Canada from epidemic areas in the central and Pacific northwest (PNW) regions of the USA. Identification of potential events as well as an assessment of epidemic severity from source locations, and prairie weather conditions, will be used to assess the need for prompt targeted crop scouting for at-risk regions of the Canadian Prairies.

This week, two documents are available from the PCDMN:

Summary of wind trajectory and cereal rust risk assessment and the need for in-crop scouting in the Prairie region, May 28 – June 3, 2019:

1. Pacific Northwest – Currently there is limited stripe rust development in the PNW, a low-moderate number of recent wind trajectories from the PNW, cool and relatively dry Prairie weather conditions, and generally early stages of Prairie crop development, especially in spring cereals.  Thus, as of June 3, 2019, the risk of stripe rust appearance from the PNW is limited and scouting for this disease is not urgent.  

2. Texas-Oklahoma corridor – In general, crops are advancing towards maturity and thus will become less of a source of rust inoculum.  There have been no recent wind trajectories from this area, cool and relatively dry Prairie weather conditions, and generally early stages of Prairie spring crop development.  Thus, as of June 3, 2019, the risk of leaf and stripe rust appearance from the Texas-Oklahoma corridor is low and scouting for these diseases is not urgent.  

3. Kansas-Nebraska corridor – Although leaf and stripe rust development continues in Kansas with a recent report of stripe rust in Nebraska, it is at low-moderate levels, although there have been reports of elevated levels in regions of Kansas.  There have been no recent wind trajectories from this area, cool and relatively dry Prairie weather conditions, and generally early stages of Prairie crop development.  Thus, as of June 3, 2019, the risk of leaf and stripe rust appearance from the Kansas-Nebraska corridor is low and scouting for these diseases is not urgent, but further development of rust in these regions may increase the risk.  

4. Where farmers or consultants noticed stripe rust development on winter wheat in the fall of 2018, it is recommended to scout winter wheat fields that have resumed growth this spring.  Scouting is especially critical where the variety being grown is susceptible to stripe rust.  Currently, there are no early spring reports of stripe rust on commercial fields of winter wheat in the prairie region.

5.  Access the full downloadable report.

Insect of the Week – Pea aphid (Hemiptera: Aphididae)

This week’s insect of the week is the pea aphid (Acyrthosiphon pisum). This long-legged, pear-shaped aphid is 3-4 mm long, light to dark green and each antennal segment is tipped by a black band. It feeds on field peas, alfalfa, broad beans, chickpeas, clover and lentils. Feeding damage can reduce yields due to lower seed formation and seed size. Leaves may turn yellow and overall plant growth can be delayed.

Pea aphids overwinter as eggs on the leaves and stems of perennial legumes (eg. clover or alfalfa crowns). They produce 2-3 generations asexually before winged females migrate to summer host crops where several more generations are produced. Winged sexual forms develop in late summer that mate and females return to winter host crops to lay eggs.

For more information about pea aphids, see our Insect of the Week page!

Pea aphid adult (L) and nymph (R)
©Mike Dolinski, MikeDolinski@hotmail.com

Weekly Update

Greetings!

Field crop entomologists across the prairies are on the move with surveying so the Weekly Update is restricted to the basics for Week 9.

Access the Weekly Update as a series of Posts for Week 09 (July 05, 2018). A similarly abridged downloadable PDF will be available Friday.   Review the “Insect of the Week” for Week 9!

Questions or problems accessing the contents of this Weekly Update?  Please e-mail either Dr. Meghan Vankosky or Jennifer Otani.  Past “Weekly Updates” can be accessed on our Weekly Update page.

Subscribe to the Blog by following these three steps!

Weather synopsis

Weather synopsis – This week staff have been busy surveying so we direct you to the AAFC Drought Watch maps in addition to the following updates.

The average temperature (14.6 °C) this past week (June 25 – July 2, 2018) was almost 2 °C warmer than long term average values (Fig. 1). 

Figure 1.  Average temperature the past seven days (June 25-July 2, 2018).

Once again, the warmest weekly temperatures occurred across MB. The 30-day (June 2-July 2) average temperature (14.3 °C) was approximately 0.5 °C warmer than long term average (Fig. 2). Average June temperatures were above normal across the entire prairie region (Fig. 3). 

Figure 2.  Average temperature the past 30 days (June 2-July 2, 2018).
Figure 3.  Monthly mean temperature differences from Normal for the month of June 2018. 
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (03Jul2018).  Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1529635048320).

Weekly and 30-day total precipitation was slightly above average (Figs. 4 and 5). The wettest (30-day) region was across eastern areas in SK and southern MB, while western SK and most of AB continue to be dry.

Figure 4.  Cumulative precipitation the past seven days (June 25-July 2, 2018).
Figure 5.  Cumulative precipitation the past 30 days (June 2-July 2, 2018).

The growing degree day map (GDD) (Base 10ºC, March 1 – July 2, 2018) is below:

The growing degree day map (GDD) (Base 5ºC, March 1 – July 2, 2018) is below:

The maps above are all produced by Agriculture and Agri-Food Canada.  Growers may wish to bookmark the AAFC Drought Watch Maps for the growing season.

Wheat midge

Wheat Midge (Sitodiplosis mosellana– As of July 2, 2018, the warm, moist conditions in Manitoba are predicted to be favourable for emergence of wheat midge adults, while dry conditions in Alberta and Saskatchewan should result in delayed emergence (Fig. 1).  Some populations may have greater than 50% emergence. Oviposition is predicted to have begun and larvae may be appearing in wheat heads. 

Figure 1. Percent wheat midge adult emergence based on model simulations for April 1-July 2, 2018.

Model runs for Saskatoon SK (Fig. 2) indicate the midge emergence is slower than  predicted emergence at Brandon MB (Fig. 3).  The delay in midge emergence is related to dryer dryer conditions in June 2018 in Saskatchewan. 

Figure 2.  Predicted wheat midge phenology for April 1-July 2, 2018, at Saskatoon SK. 
Figure 3.  Predicted wheat midge phenology for April 1-July 2, 2018, at Brandon MB.

Monitoring:

When monitoring wheat fields, pay attention to the synchrony between flying midge and anthesis.  

In-field monitoring for wheat midge should be carried out in the evening (preferably after 8:30 pm or later) when the female midges are most active. On warm (at least 15ºC), calm evenings, the midge can be observed in the field, laying their eggs on the wheat heads (photographed by AAFC-Beav-S. Dufton & A. Jorgensen below). Midge populations can be estimated by counting the number of adults present on 4 or 5 wheat heads. Inspect the field daily in at least 3 or 4 locations during the evening.

REMEMBER that in-field counts of wheat midge per head remain the basis of economic threshold decision.  Also remember that the parasitoid, Macroglenes penetrans (photographed by AAFC-Beav-S. Dufton below), is actively searching for wheat midge at the same time.  Preserve this parasitoid whenever possible and remember your insecticide control options for wheat midge also kill these beneficial insects which help reduce midge populations.

Economic Thresholds for Wheat Midge:

a) To maintain optimum grade: 1 adult midge per 8 to 10 wheat heads during the susceptible stage.

b) For yield only: 1 adult midge per 4 to 5 heads. At this level of infestation, wheat yields will be reduced by approximately 15% if the midge is not controlled.

Inspect the developing kernels for the presence of larvae and the larval damage. 

Click here to review the 2018 wheat midge forecast map.  

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.  Additionally, more information 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

Bertha armyworm (Lepidoptera: Mamestra configurata– BAW populations are predicted to be in the larval stages and may have begun feeding within the plant canopy on leaves. Figure 1 illustrates that BAW oviposition is complete and  that the population is in the larval stage for populations near Brandon (Fig. 1). 

Figure 1.  Predicted BAW phenoloyg at Brandon MB. 
Values are based on model simulations for April 1-July 2, 2018 (projected to July 10, 2018)

Many thanks to those who are checking a bertha armyworm pheromone trap on a weekly basis.  Please use the reference photo below kindly shared by Saskatchewan Agriculture to aid your identification and reporting of trap interceptions.  Note the kidney-bean white-patterned shape on each forewing but also know other cutworm species can resemble bertha armyworm moths.  Check carefully and thanks for your help!

Monitoring:

  • Larval sampling should commence once the adult moths are noted. 
  • Sample at least three locations, a minimum of 50 m apart. 
  • At each location, mark an area of 1 m2 and beat the plants growing within that area to dislodge the larvae. 
  • Count them and compare the average against the values in the economic threshold table below:  

Scouting tips:

  • Some bertha armyworm larvae remain green or pale brown throughout their larval life. 
  • Large larvae may drop off the plants and curl up when disturbed, a defensive behavior typical of cutworms and armyworms. 
  • Young larvae chew irregular holes in leaves, but normally cause little damage. The fifth and sixth instar stages cause the most damage by defoliation and seed pod consumption. Crop losses due to pod feeding will be most severe if there are few leaves. 
  • Larvae eat the outer green layer of the stems and pods exposing the white tissue. 
  • At maturity, in late summer or early fall, larvae burrow into the ground and form pupae.

Keep track of the Provincial Entomologist Updates for the latest in-season pheromone trap monitoring results for 2018.  

Saskatchewanians can view the latest pheromone trap interceptions below kindly provided by Saskatchewan Agriculture.

Albertans can access the online reporting map (screenshot retrieved 04Jul018 provided below for reference:

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 new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.

Predicted grasshopper development

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).  

As of July 2, 2018, the predictive model output indicated that the average instar = 3.7, with 1st instar (5%), 2nd (12%), 3rd (24%), 4th (34%), 5th (23%), and 2.4% in the adult stage. The most rapid development occurred across southern MB and southeast SK (Fig. 1). 

Figure 1.  Grasshopper development (average instar stage) based on model simulations for April 1-July 2, 2018.

Model output for Saskatoon illustrates that populations are primarily in the 4th and 5th instars with appearance of a few adults (Fig. 2).   By comparison, model output based on long-term climate data indicates that grasshopper populations should on average only be in the 3rd and 4th instars (Fig. 3).

Figure 2.  Predicted grasshopper phenology at Saskatoon SK.
Values are based on model simulations for April 1-July 2, 2018.
Figure 3.  Predicted grasshopper phenology at Saskatoon SK.
Values are based on model simulations for Long Term Climate Normals.

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.

● Starting 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 end point 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 related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Lygus in canola

Lygus bugs (Lygus spp.) – As of July 2, 2018, the model indicates the Lygus populations range from the 1st instar stage to adults with most of the population being at the 4th and 5th instar stages (Fig. 1).  Warmer temperatures have resulted in rapid development in southern Manitoba and southeast Saskatchewan. 

Figure 1.  Predicted Lygus development (average instar stage) based on model simulations for April 1-July 2, 2018.

This week, model runs were conducted for Saskatoon, Lethbridge and Grande Prairie to compare site specific development. The Lygus model output suggests that Saskatoon populations should be primarily be in the 3-5th instar stages (Fig. 2) with development predicted to be marginally slower in Lethbridge (Fig. 3). Populations near Grande Prairie are predicted to be in the 3rd instar stage (Fig. 4). 

Figure 2. Predicted Lygus phenology for April 1-July 2, 2018, for Saskatoon SK.
Figure 3. Predicted Lygus phenology for April 1-July 2, 2018, for Grande Prairie AB.
Figure 4.  Predicted Lygus phenology for April 1-July 2, 2018, for Lethbridge AB.

Remember – The economic threshold for Lygus in canola is applied at late flower and early pod stages.  

Adult L. lineolaris (5-6 mm long) (photo: AAFC-Saskatoon).
Fifth instar lygus bug nymph (3-4 mm long) (photo:  AAFC-Saskatoon).

Damage: Lygus bugs have piercing-sucking mouthparts and physically damage the plant by puncturing the tissue and sucking plant juices. The plants also react to the toxic saliva that the insects inject when they feed. Lygus bug infestations can cause alfalfa to have short stem internodes, excessive branching, and small, distorted leaves. They feed on buds and blossoms and cause them to drop. They also puncture seed pods and feed on the developing seeds causing them to turn brown and shrivel.

Begin monitoring canola when it bolts and continue until seeds within the pods are firm. Since adults can move into canola from alfalfa, check lygus bug numbers in canola when nearby alfalfa crops are cut.

Sample the crop for lygus bugs on a sunny day when the temperature is above 20°C and the crop canopy is dry. With a standard insect net (38 cm diameter), take ten 180° sweeps. Count the number of lygus bugs in the net.

Repeat the sampling in another 14 locations. Samples can be taken along or near the field margins. Calculate the cumulative total number of lygus bugs and then consult the sequential sampling chart (Figure C). If the total number is below the lower threshold line, no treatment is needed. If the total is below the upper threshold line, take more samples. If the total is on or above the upper threshold line, calculate the average number of lygus bugs per 10-sweep sample and consult the economic threshold table.

Sequential sampling for lygus bugs at late flowering stage in canola.

The economic threshold for lygus bugs in canola covers the end of the flowering (Table 1) and the early pod ripening stages (Table 2). Once the seeds have ripened to yellow or brown, the cost of controlling lygus bugs may exceed the damage they will cause prior to harvest, so insecticide application is not warranted.

Remember that insecticide applications at bud stage in canola have not been proven to result in an economic benefit in production.  The exception to this is in the Peace River region where early, dry springs and unusually high densities of lygus bug adults can occasionally occur at bud stage.  In this situation, high numbers of lygus bugs feeding on moisture-stressed canola at bud stage is suspected to result in delay of flowering so producers in that region must monitor in fields that fail to flower as expected.

Table 1.  Economic thresholds for lygus bugs in canola at late flowering and early pod stages (Wise and Lamb 1998).

1 Canola crop stage estimated using Harper and Berkenkamp 1975).
2 Economic thresholds are based on an assumed loss of 0.1235 bu/ac per lygus bug caught in 10 sweeps (Wise and Lamb. 1998. The Canadian Entomologist. 130: 825-836).

Table 2.  Economic thresholds for lygus bugs in canola at pod stage (Wise and Lamb 1998).

 3 Economic thresholds are based on an assumed loss of 0.0882 bu/ac per lygus bug caught in 10 sweeps (Wise and Lamb. 1998. The Canadian Entomologist. 130: 825-836).

Biological and monitoring information related to Lygus in field crops is posted by the provinces of Manitoba or Alberta fact sheets or the Prairie Pest Monitoring Network’s monitoring protocol.  Also refer to the Lygus pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.

Provincial Insect Pest Reports

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

Manitoba‘s Insect and Disease Updates for 2018 can be accessed here. At posting time, specific updates (June 20, and 27) would not open on the Manitoba website – please keep trying though!

Saskatchewan‘s Crop Production News for 2018 is posted with Report #3 now available. Insect monitoring information is included in the article, “Canola plants disappearing? Scout the field to look for cutworm damage”. Saskatchewan growers can review articles to assess plant stand densities in flax or canola, and for flea beetles, pea leaf weevils. Also note the following diamondback moth pheromone trap interception counts from across the regions (updated June 27, 2018):

Alberta Agriculture and Forestry’s Call of the Land regularly includes insect pest updates from Scott Meers. The most recent Call of the Land (posted July 4, 2018, by Mark Cutts) highlights the importance of field scouting now. You can review the Weekly Insect Update (posted by Scott Meers on June 21, 2018) noting that bertha armyworm moths were detected this first week of pheromone monitoring (check online map), onset of flowering in canola signalling the need for in-field monitoring for cabbage seedpod weevil, continued grasshopper calls from the south and advice to scout now while nymphs are easier to manage, Nutall’s blister beetle transiently showing up in some fields (blister beetle post), and the presence of the beneficial stiletto fly larvae which is a predator within the soil profile and targets wireworm larvae.

Download the Field Guide

If you haven’t downloaded the FREE field guide yet, please do so now!

Field Crop and Forage Pests and their Natural Enemies in Western Canada: IDENTIFICATION AND MANAGEMENT FIELD GUIDE

The 152-page, full-colour field guide, now available online, is designed to help you make informed decisions in managing over 90 harmful pests of field and forage crops in Western Canada. Better decision making helps save time and effort and eliminates unnecessary pesticide applications to improve your bottom line. The guide also helps the reader identify many natural enemies that prey on or parasitize pest insects. Recognizing and fostering populations of natural enemies will enhance their role in keeping or reducing pest populations below economic levels.

Find links to download the FREE Insect Field Guide.

Previous Posts

The following is a list of 2018 Posts – click to review:

Alfalfa weevil – Week 6

Cabbage seedpod weevil – Week 8 
Cereal aphid manager (CAM) – Week 2
Cereal leaf beetle – Week 5
Cereal leaf beetle larvae request – Week 8
Crop protection guides – Week 2
Crop reports – Week 8
Cutworms – Week 4

Diamondback moth – Week 7

Field heroes – Week 8
Flea beetles – Week 4

Monarch migration – Week 8

Pea leaf weevil – Week 8
PMRA Pesticide Label Mobile App – Week 4

Scouting charts (canola and flax) – Week 3

Ticks and Lyme Disease – Week 4

Weather radar – Week 3
West nile virus – Week 8
Wind trajectories – Week 6
Wireworm distribution maps – Week 6
White grubs in fields – Week 8

Weekly Update – Wheat midge

Wheat Midge (Sitodiplosis mosellana– Reminder – The previous Insect of the Week (Week 7) features wheat midge!  

Simulation modelling is used to predict wheat midge emergence across the Canadian prairies.  The model has not changed significantly from last week. The map below predicts the geographic distribution and corresponding accumulation of heat units necessary for wheat midge to emerge from puparia developing in the soil.  



Monitoring:

When monitoring wheat fields, pay attention to the synchrony between flying midge and anthesis.  

In-field monitoring for wheat midge should be carried out in the evening (preferably after 8:30 pm or later) when the female midges are most active. On warm (at least 15ºC), calm evenings, the midge can be observed in the field, laying their eggs on the wheat heads (photographed by AAFC-Beav-S. Dufton & A. Jorgensen below). Midge populations can be estimated by counting the number of adults present on 4 or 5 wheat heads. Inspect the field daily in at least 3 or 4 locations during the evening.



REMEMBER that in-field counts of wheat midge per head remain the basis of economic threshold decision.  Also remember that the parasitoid, Macroglenes penetrans (photographed by AAFC-Beav-S. Dufton below), is actively searching for wheat midge at the same time.  Preserve this parasitoid whenever possible and remember your insecticide control options for wheat midge also kill these beneficial insects which help reduce midge populations.





Economic Thresholds for Wheat Midge:

a) To maintain optimum grade: 1 adult midge per 8 to 10 wheat heads during the susceptible stage.


b) For yield only: 1 adult midge per 4 to 5 heads. At this level of infestation, wheat yields will be reduced by approximately 15% if the midge is not controlled.

Inspect the developing kernels for the presence of larvae and the larval damage. 



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.  

NEW – Alberta Agriculture and Forestry has also released a YouTube video describing in-field monitoring for wheat midge this week.  


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.

Weekly Update – White grubs in field crops

Scarabaeidae – Reminder – Each June brings scattered reports across the Prairies of white grubs associated with crop damage.  In fact, several species of Aphodius, Phyllophaga, Polyphylla or even small Aetenius produce larvae described as “white grubs”.  


Recently, crop damage reports have been associated with a grub identified as the larvae of the beetle Aphodius distinctus (see below). This common beetle is not known to be a pest, but there is an ongoing effort to gather information to develop a ‘pest’ profile.  Additional information is online at Top Crop Manager. Please send reports of this insect and associated information to Dr. Kevin Floate (Agriculture and Agri-Food Canada, Lethbridge, AB).

Weekly Update – Painted Lady Butterfly

Painted Lady Butterflies (Lepidoptera: Vanessa cardui) – Back on Week 6, we posted information and links related to the adult.  


UPDATE – This week, Alberta Agriculture & Forestry reminded their network of cooperators to watch for V. cardui larvae because the species has a broad host range and can feed on soybean (Action threshold=>25% defoliation), sunflowers, borage and dry beans in addition to several species of thistles (including Canada thistle) and mallow. 

In addition to the Week 6 information linking to the Butterflies of Canada entry for Vanessa cardui, the Butterflies and Moths of North America website tracks confirmed sightings of V. cardui (screenshot provided below).

The Butterflies and Moths of North America website also includes some verified photos of larvae to compare to when scouting.  Here’s screenshot below of the photo provided by T. Stout to hasten the need to link to this valuable resource!






Weekly Update – Monarch migration

We again track the migration of the Monarch butterflies as they move north by checking the 2017 Monarch Migration Map!  A screen shot of the map has been placed below as an example (retrieved 22Jun2017) but follow the hyperlink to check the interactive map!  They’ve migrated into southern Manitoba (various), southeast Saskatchewan (near Rhein), and now Alberta (near Sylvan Lake)! 

Weekly Update – Previous Posts

The following is a list of 2017 Posts – click to review:


Alfalfa weevil (Week 7)


Brood X Cicadas



Cabbage seedpod weevil (Week 8)

Canola scouting chart
Cereal leaf beetle
Crickets with your popcorn
Crop protection guides
Crop reports (Week 8)
Cutworms

Diamondback moth


Flax scouting chart

Flea beetles


Grasshopper development (Week 8)

Iceberg reports


Lily leaf beetle



Pea leaf weevil
PMRA Pesticide Label Mobile App
Provincial Insect Pest Reports (Week 8)


Nysius niger (Week 8)

Ticks and Lyme disease


Weather radar


Wind trajectories


Insect of the Week – Cereal aphids

This week’s Insect of the Week is the group of aphids known
as cereal aphids. These aphids include the corn leaf aphid, the English grain
aphid, the oat-birdcherry aphid and the Russian wheat aphid. They feed on
cereal crops and are vectors of viruses, causing lower crop quality and yield. There are several natural enemies of cereal aphids, including various species of wasps and beetles. 

For more information on cereal aphids, see our Insect of the Week page. 

English grain aphid – adult, nymph (Tyler Wist, AAFC)



Remember the NEW Cutworm Field Guide is free and downloadable in 2017!

Weekly Update – Greetings!

Greetings!

This week AAFC Staff are out surveying so the Weekly Update will be released in segments.  Please access the series of Posts for Week 9 (Jun 29, 2017) to reach the most up-to-date information.   



Remember, if we’re in the field, you should be too!


Questions or problems accessing the contents of this Weekly Update?  Please e-mail either Dr. Owen Olfert or Jennifer Otani.  Past “Weekly Updates” can be accessed on our Weekly Update page.

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Weather Synopsis

Weather synopsis – Our AAFC Staff are busy surveying this week so be sure to check back for updates!


Precipitation for the growing season is presented below (April 1-June 27, 2017) followed by the precipitation expressed as Percent of Normal for the same period.



Over the past seven days, the greatest precipitation fell in northern growing areas along areas typically grouped as Boreal Plains (June 21-27, 2017).  Southern Alberta, southeast Saskatchewan and southwest Manitoba received the lowest amounts of precipitation over the same period.



The lowest temperatures across the prairies over the past seven days (June 21-27, 2017) are mapped below.  Although there was little chance of frost, much of the prairies recorded lows ranging from 0-4°C.



In contrast, the highest temperatures recorded over the past seven days (June 21-27, 2017) are presented below.  The field crops in some of these areas endured daily fluctuations of 20-25°C.

The updated growing degree day map (GDD) (Base 5ºC, March 1 – June 25, 2017) is below:



While the growing degree day map (GDD) (Base 10ºC, March 1 – June 25, 2017) is below:


The maps above are all produced by Agriculture and Agri-Food Canada.  Growers may wish to bookmark the AAFC Drought Watch Maps for the growing season.

Weekly Update – Predicted Bertha Armyworm Development

Bertha armyworm (Lepidoptera: Mamestra configurata– Bertha armyworm should be in the adult stage across the prairies this week.  The map illustrates predicted appearance of adults (percent of the population) across the southern prairies.

For those monitoring BAW pheromone traps, compare trap “catches” to the following reference photo kindly shared by Saskatchewan Agriculture:



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 new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.

Cabbage seedpod weevil

Cabbage seedpod weevil (Ceutorhynchus obstrictus) –  Reminder – There is one generation of CSPW per year and the overwintering stage is the adult which is an ash-grey weevil measuring 3-4mm long (Refer to lower left photo).  Adults typically overwinter in soil beneath leaf litter within shelter belts and roadside ditches.

CSPW emerge from overwintering in the spring as soil temperatures warm to ~15°C.  CSPW utilize several flowering hosts including wild mustard, flixweed, hoary cress, stinkweed and volunteer canola.  CSPW move to canola during the bud to early flower stages and will feed on pollen and buds, causing flowers to die.

The map below reflects CSPW densities observed in 2015.  Growers situated within or adjacent to areas of the map highlighted yellow, orange and red will need to be scouting with a sweep-net as their canola fields initiate flowering.




Monitoring:  
 ● Begin sampling when the crop first enters the bud stage and continue through the flowering. 
 ● Sweep-net samples should be taken at ten locations within the field with ten 180° sweeps per location.  
 ● Count the number of weevils at each location. Samples should be taken in the field perimeter as well as throughout the field.  
 ● Adults will invade fields from the margins and if infestations are high in the borders, application of an insecticide to the field margins may be effective in reducing the population to levels below which economic injury will occur.  
 ● An insecticide application is recommended when three to four weevils per sweep are collected and has been shown to be the most effective when canola is in the 10 to 20% bloom stage (2-4 days after flowering starts). 
 ● Consider making insecticide applications late in the day to reduce the impact on pollinators.  Whenever possible, provide advanced warning of intended insecticide applications to commercial beekeepers operating in the vicinity to help protect foraging pollinators.  
 ● High numbers of adults in the fall may indicate the potential for economic infestations the following spring.

Damage: Adult feeding damage to buds is more evident in dry years when canola is unable to compensate for bud loss.  Adults mate following a pollen meal then the female will deposit a single egg through the wall of a developing pod or adjacent to a developing seed within the pod (refer to lower right photo).  Eggs are oval and an opaque white, each measuring ~1mm long.  Typically a single egg is laid per pod although, when CSPW densities are high, two or more eggs may be laid per pod.


There are four larval instar stages of the CSPW and each stage is white and grub-like in appearance ranging up to 5-6mm in length (refer to lower left photo).  The first instar larva feeds on the cuticle on the outside of the pod while the second instar larva bores into the pod, feeding on the developing seeds.  A single larva consumes about 5 canola seeds.  The mature larva chews a small, circular exit hole from which it drops to the soil surface and pupation takes place in the soil within an earthen cell.  Approximately 10 days later, the new adult emerges to feed on maturing canola pods.  Later in the season these new adults migrate to overwintering sites beyond the field.


Please find additional detailed information for CSPW in fact sheets posted by Alberta Agriculture and ForestrySaskatchewan Agriculture, or the Prairie Pest Monitoring Network.


Also watch provincial reports for updates on surveying underway now.  Alberta Agriculture & Forestry has released a new live CSPW map and online reporting tool for growers.  A screenshot (retrieved 29 Jun 2016) is included below.


Provincial Insect Pest Reports

Provincial entomologists provide insect pest updates throughout the growing season so we have attempted to link to their most recent information: 

– Manitoba’s Insect and Disease Update which includes alfalfa weevil and descriptions to aid scouting for cereal leaf beetle (June 22, 2016, prepared by John Gavloski and Pratisara Bajracharya).

– Saskatchewan’s Insect Report which mentions redbacked cutworms but emphasizes scouting for cabbage seedpod weevil, wheat midge and grasshoppers (Issue 4, prepared by Scott Hartley).
– Watch for Alberta Agriculture and Forestry’s Call of the Land for updates from Scott Meers  who recently provided an update (posted on June 23, 2016including cabbage seedpod weevil on early canola in southern Alberta, cereal leaf beetle reports on wheat and barley but also the benefits of its parasitoid, Tetrastichus julis.

Weekly Update – Crop reports

Crop reports are produced by:

– Manitoba Agriculture, Rural Development (June 27, 2016)
– Saskatchewan Agriculture Crop Report (June 20, 2016)

– Alberta Agriculture and Forestry (for June 21, 2016)

Weekly Update – Previous Posts

The following is a list of previous 2016 Posts – click to review:

Canola scouting chart

Wind trajectories
Cutworms
Flea beetles in canola
Predicted cereal leaf beetle development
Predicted lygus bug development
Predicted wheat midge development
Pea leaf weevil monitoring
Crop protection guides
Using Environment Canada’s radar maps to follow precipitation events
Iceburg reports

Monarch migration

Weekly Update

Greetings!

A downloadable PDF version of the complete Weekly Update for Week 9 (June 29, 2016) can be accessed here.  

This edition includes the “Insect of the Week” featuring beneficial arthropods in 2016!

Subscribe to the Blog by following the instructions posted here!  You can receive automatic updates in your inbox through the growing season.



Questions or problems accessing the contents of this Weekly Update?  Please e-mail either Dr. Owen Olfert or Jennifer Otani.  Past “Weekly Updates” are very kindly archived to the Western Forum website by webmaster, Dr. Kelly Turkington.  

Weekly Update – Weather Synopsis

Staff are busy surveying so some maps are not available this week.

Warmer temperatures were observed throughout the prairies and the west was drier compared to the east.


The Accumulated Precipitation the past 7 days (June 22-28, 2016) is below:



The map below reflects the Accumulated Precipitation for the Growing Season so far for the prairie provinces (i.e., May 1-June 26, 2016):





Compared to last week, overnight temperatures were warmer during the past 7 days.  The map below shows the Lowest Temperatures the Past 7 Days (June 22-28, 2016) across the prairies:



The map below shows the Highest Temperatures the Past 7 Days (June 22-28, 2016):





The updated growing degree day map (GDD) (Base 5ºC, March 1 – June 26, 2016) is below:





While the growing degree day map (GDD) (Base 10ºC, March 1 – June 26, 2015) is below:




The maps above are all produced by Agriculture and Agri-Food Canada.  Growers may wish to bookmark the AAFC Drought Watch Maps for the growing season.

Weekly Update – Bertha Armyworm

Bertha armyworm (Lepidoptera: Mamestra configurataThis week, moths are expected to complete their yearly flight.  Reporting sites across the prairies have generally reported lower cumulative interceptions with some exceptions in Saskatchewan.  

Provincial staff coordinate BAW pheromone trapping across the prairies and summarize cumulative counts in report or map formats:
● Saskatchewanians.… Male moths have been intercepted at multiple sites in Saskatchewan with some sites reporting higher risk values (Insect Report-Issue #4, prepared by S. Hartley).  
● Manitobans.…. Low numbers of male moths have been intercepted throughout the province but review the values in the most recent Insect and Disease Report prepared by J. Gavloski and posted June 22, 2016.  

● Albertans.…..  Refer to the live 2016 map reporting Bertha armyworm pheromone trap interceptions.  A copy of the map (retrieved June 29, 2016) is below for reference.

Weekly Update – Grasshoppers

Grasshoppers (Acrididae) – Previous model predictions related to hatch and nymphal instar development can be reviewed here.  


The following image showing various stages of Camnulla pellucida is provided below – note that adults have wings extending the length of the abdomen whereas nymphs lack wings but develop wing buds that will eventually mature to wings.  


Generally, the economic threshold for grasshoppers in cereals is 8-12 per square metre but will vary by crop and growing conditions.

Figure 1. Life stages of Camnulla pellucida which including eggs, first-fifth instar nymphs and adult (L-R).
Biological and monitoring information related to grasshoppers in field crops is posted by the provinces of ManitobaSaskatchewanAlbertaBritish Columbia and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.

Weekly Update – Swede midge

Swede midge (Contarinia nasturtii)  – Reminder – Pheromone traps captured the first swede midge of 2016 between May 25 and 31 in northeastern Saskatchewan.  This is substantially earlier (6-7 weeks) compared to 2014 and 2015. 

The earlier emergence pattern is likely due to the mild winter and warm spring weather combined with adequate moisture levels. Emergence traps indicate a moderate number of swede midge have emerged near Carrot River, Saskatchewan, and producers should monitor their canola fields for damage symptoms

Figure 1. Swede midge infested canola buds which are enlarged with sepals fused together. 


Figure 2.  Swede midge large (~1mm long; yellowish-white) feeding within canola flower.


Swede midge scouting tips for in-field monitoring:
• Watch for unusual plant structures and plant discolourations then follow-up by closely scrutinizing the plant for larvae.
• The growing tip may become distorted and produce several growing tips or none at all, young leaves may become swollen, crinkled or crumpled and brown scarring caused by larval feeding may be seen on the leaf petioles and stems.
• Flowers may fail to open.
• Young plants that show unusual growth habits should be examined carefully for damage and larvae; especially if the sticky liners have many flies resembling midges (swede midges are about the size of orange blossom wheat midge but are not orange).
• Larvae can be seen with a hand lens.
• Refer to the Canola Watch article by Dr. Julie Soroka for more information on swede midge and watch for a new Ontario fact sheet produced by Baute et al. 2016.

Note the distribution map of confirmed symptoms and populations of swede midge (red dots) on the Canadian prairies  (Soroka and Andreassen 2015).


Weekly Update – Cereal leaf beetle

Cereal leaf beetle (Oulema melanopus) – Reminder – Back in May, the cereal leaf beetle (CLB) bioclimatic model was utilized to help predict when eggs and larvae might appear in fields along with its parasitoid, Tetrastichus julis

Recall the following (posted May 25, 2016) – Predicted dates of peak emergence of CLB eggs and larvae:




Cereal leaf beetle larvae hatch from eggs 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. 1).  When the larva completes its growth, it drops to the ground and pupates in the soil.  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.

Figure 1.  Larval stage of Oulema melanopus with characteristic feeding damage visible on leaf.

Monitoring:
Give priority to 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 your 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. 

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 new “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide”.

Weekly Update – Alfalfa weevil

Alfalfa Weevil (Hypera postica) – 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 9mm long.  Alfalfa growers are encouraged to check the Alfalfa Weevil Fact Sheet prepared by Dr. Julie Soroka (AAFC-Saskatoon).



Updated – Degree-day maps of base 9°C are now being produced by Soroka, Olfert, and Giffen (2016) using the Harcourt/North Dakota models.  The aim or the modelling is to predict the development of Alfalfa weevil (Hypera postica) across the prairies and to help growers time their in-field scouting as second-instar larvae are predicted to occur.  Compare the following predicted development stages and degree-day values copied below (Soroka 2015) to the map below.




For the week of June 26, 2016, the following map predicts the developmental stages for alfalfa weevil and corresponding degree-days.  Areas highlighted orange are predicted to find fourth instar larvae so scout for major leaf feeding then compare larval densities to the action threshold for alfalfa weevil!



Economic thresholds for Alfalfa weevil (adapted from Soroka 2015) vary by crop type (hay or seed), area fed upon and larval densities.

In hay fields, forage losses can be economic if one or more of the following symptoms are noted:
● if 25-50 % of the leaves on the upper one-third of the stem show damage, or
● if 50-70% of the terminals are injured, or
● if 1 to 3 third or fourth instar larvae occur per stem (with shorter stems having lower economic thresholds and 3 or more larvae requiring treatment no matter what the alfalfa height), or 
● 20-30 larvae per sweep occur when 12% leaf loss is acceptable.
● Also consider these two points:
      1. Early cutting of the first growth of alfalfa or insecticide treatment will reduce alfalfa weevil populations.
      2. If the hay crop value is high and weevil injury is seen or 2 or more larvae per stem reappear in regrowth after cutting, insecticide may be necessary (if a second cut is anticipated). 

In alfalfa seed fields:
● Economic thresholds are 20-25 third to fourth instar larvae per sweep or 35-50% of the foliage tips showing damage. 
● Thresholds increase with the height of the alfalfa, and decrease in drought conditions. 
● Also know that several small wasps parasitize alfalfa weevil larvae and adults, and in the past these natural control agents kept the weevil in check in most years. One of these wasps, Bathyplectes curculionis (Thomson), parasitizes alfalfa weevil in Alberta and Saskatchewan, and is now found in Manitoba.

Weekly Update – Small scarab beetle

Small scarab beetle (Coleoptera: Aphodius distinctus) – Reminder – This is the time of summer that farmers will be seeing larvae of a small scarab beetle (Aphodius distinctus) in their fields.  There have been scattered reports each June of large numbers of beetle grubs in crops associated with crop damage (e.g., canola, corn, dry bean, onion, pea).


Please help researchers compile information related to this species so they might confirm its pest status!  Information is posted about the beetle and the survey.  Here’s how you can help:

1. Please send reports of high white grub densities and associated crop damage to Kevin.Floate@agr.gc.ca (403-317-2242). 

2. Live larvae accompanied by the following field information would be extremely helpful please – contact Dr. Kevin Floate if you have a sample!

3. Include answers to the following so the pest status for this species can be ascertained:  
     – Previous crop?
     – Legal land location or latitude+longitude?
     – Irrigated or not?
     – Was composted manure added this spring?
     – Surface residue in spring?


Weekly Update – Multitude of Mayflies!

Mayflies on your radar?!  Unusually large numbers – enough to repeatedly show up on eastern weather radar systems in North America, have been emerging and they’ve made the news!  


See and read more about mayflies on Bug Guide which is where this wonderful photo by Werner Eigelsreiter is posted.

Mayflies occur in rivers, streams, ponds and lakes and they are an important food source for several species of fish.  The aquatic nymph develops through several stages then moves to the surface to molt into a winged sub-adult that flies to nearby plants and molts again into an adult that usually live only for 48-72 hrs.  

Mayflies belong to the Order Ephemeroptera and you can see and read more about them on Bug Guide’s website.  

Insect of the Week – Rove beetle

Rove Beetle (predator and parasitoid)

Last year, the focus of the Insect of the Week was crop pests. This year, we’re changing things up and highlighting the many natural enemies that help you out, silently and efficiently killing off crop pests. [note: featured Insects of the Week in 2015 are available on the Insect of the Week page] 

This week’s Insect of the Week is the rove beetle (Delia spp.), is a generalist predator. The adult feeds on aphids, mites and larvae of many species under plant debris, rocks, dead animals, dung and other materials. The rove beetle larvae have similar hosts as the adult; the larvae of Aleochara spp parasitize various fly species including cabbage root maggot.

For more information about rove beetle, the pests it controls and other important crop and forage insects, see the new Field Crop and Forage Pests and their Natural Enemies in Western Canada – Identification and Management Field Guide for identification, life cycle and conservation options (download links for field guide available on the Insect of the Week page).

Adult rove beetle. (c) AAFC-Tyler Wist