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 Wk07 (released June 8, 2020).

Weekly Update

This time it’s a BIG Weekly Update – several predictive model updates have been generated this week! Find updated information for bertha armyworm, grasshoppers, cereal leaf beetle, alfalfa weevil, wheat midge and pea leaf weevil.  A new Pests & Predators podcast is available and much more.  Keep scrolling down and it’s time to get in fields to scout!

Access information to support your in-field insect monitoring efforts in the complete Weekly Update either as a series of Posts for Week 7 OR a downloadable PDF.

Stay Safe!

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

Barley Pests / Feature Entomologist: John Gavloski

This week’s Insect of the Week feature crop is barley, an important Prairie cereal (and not just because it’s an essential ingredient for beer). Our feature entomologist this week is John Gavloski (Manitoba Agriculture and Resource Development).

Barley Crop
cc by 2.0 Ian Britton

Without barley, there would be no beer. And the world wept. Thankfully, plenty of barley is grown on the Prairies, not just for beer but also as feed. Roughly 96% of the barley grown on the Prairies is split equally between Alberta and Saskatchewan. In 2019, total Prairie production on 2.85 million hectares (7.05 million acres) was 9.93 million metric tonnes (10.95 million US tons).

A number of pests can be found in barley fields. Monitoring and scouting protocols as well as economic thresholds (when available) are found in the 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. More detailed protocols exist for some of the pests.

Barley Pests
  • Army cutworm
  • Armyworm
  • Barley thrips
  • Black grass bugs
  • Brown wheat mite
  • Cereal leaf beetle
  • Chinch bug
  • Corn leaf aphid
  • Darksided cutworm
  • Dingy cutworm
  • English grain aphid
  • Fall armyworm
  • Fall field cricket
  • Glassy cutworm
  • Grasshoppers
  • Green-tan grass bugs
  • Greenbug
  • Haanchen barley mealybug
  • Mormon cricket
  • Oat-birdcherry aphid
  • Pale western cutworm
  • Redbacked cutworm
  • Rice leaf bug
  • Russian wheat aphid
  • Say stink bug
  • Variegated cutworm
  • Wheat head armyworm
  • Wheat stem maggot
  • Wireworms

ENTOMOLOGIST OF THE WEEK: John Gavloski

Name: John Gavloski
Affiliation: Manitoba Agriculture and Resource DevelopmentContact Information: John.Gavloski@gov.mb.ca, @Johnthebugguy

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

I organize annual monitoring programs for diamondback moth, bertha armyworm and grasshoppers in Manitoba. I am also currently monitoring the distribution and levels of cabbage seedpod weevil and pea leaf weevil in Manitoba. 

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

Grasshoppers, as a group of insects, are quite interesting. In Canada there are about 180 species of grasshoppers, but only a few cause economic damage to crops. I have enjoyed the sights, sounds, and tastes of grasshoppers; yes you read that last part correctly! The pest species like dry conditions. In late-spring or early-summer we often start to see species of grasshoppers with colourful and almost butterfly-like hind wings; when they fly you get flashes of orange, yellow, and black. None of these are pest species, but cool to observe. Others are good mimics, and can blend in with sand, gravel or leaves very well. Late in the summer it is always a treat to hear the singing of grasshoppers, especially the katydids, which are not pests and are usually green with long antennae. And yes, I have eaten grasshoppers, at an entomology conference featuring an insect banquet. I did enjoy them – anything cooked in a flavourful sauce is good, but I suggest  removing the wings if you ever try them – too much cuticle. I guess this bout of entomophagy makes me and the other entomologists at the banquet natural enemies of grasshoppers.

What is your favourite beneficial insect?

This is a really tough, as there are so many fascinating beneficial insects! Hover flies are a family of flies (Syrphidae) with many beneficial and interesting attributes. They are predators, pollinators, masters of mimicry, and it is fun to watch the larvae feed. There are 539 species of hover flies in Canada. Adults are good pollinators that are great at mimicking wasps and bees, come in a variety of sizes, and can often be seen hovering near flowers. The slug-like, legless larvae of many hover flies feed on aphids by impaling an aphid with its mouthparts, holding it up, sucking the fluids out of the body, and discarding the exoskeleton. It makes for a great show. I try to raise awareness about hover flies so that people know they are not wasps or bees, cannot sting and are beneficial in many ways.

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

I am tracking the distribution and densities of cereal leaf beetle in Manitoba. It was first found in the northwest region of Manitoba in 2009. A small parasitic wasp called Tetrastichus julis was introduced shortly after cereal leaf beetles were detected. I have been tracking the spread and densities of both the pest and the parasitoid across Manitoba. Cereal leaf beetle larvae are sent to AAFC-Lethbridge where they are dissected to determine the level of parasitism. If the level is low, parasitoids are sent to me for release in Manitoba in areas where they may be lacking. I will be assessing levels of cereal leaf beetle larvae again this year, and hopefully releasing more wasps if needed.

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

I enjoy doing presentations for academics, producers, agronomists, and the general public. I co-produce the Manitoba Crop Pest Update from May through August. This is an opportunity to communicate current types and levels of insect activity in Manitoba. I like producing factsheets, for pests and beneficial insects, that are available on our department’s website. An information campaign that has been fun to contribute to is “Field Heroes”, which provides information to help raise awareness and provide information about beneficial insects. Until several of the rural newspapers in Manitoba closed recently, I produced a monthly column called “Incredible Creatures” that several of the rural newspapers carried.

Weekly Update

Greetings!

Access the complete Weekly Update either as a series of Posts for Week 07 (May 23, 2019) OR a downloadable PDF.  Check out the Insect of the Week.

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!

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:

Synopsis of May 21, 2019, Weekly Cereal Rust Risk Report: 
Wind trajectory and cereal rust risk assessment and need for in-crop scouting in the Prairie region, May 21, 2019.

1.  Pacific Northwest – Given limited stripe rust development in the PNW, a low number of recent wind trajectories from the PNW, cool and relatively dry Prairie weather conditions, and early stages of Prairie crop development, as of May 21, 2019, the risk of stripe rust appearance from the PNW is limited and scouting for this disease is not urgent.  

2.  Texas-Oklahoma corridor – Although leaf and stripe rust development continues in this corridor, especially Oklahoma, the disease is mainly affecting the lower canopy at generally low levels.  In addition, crops are advancing towards maturity and thus will become less of a source of rust inoculum.  There have been a low number of recent wind trajectories from this area, cool and relatively dry Prairie weather conditions, and early stages of Prairie crop development.  Thus, as of May 21, 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 this corridor, it is at low-moderate levels and mainly in the middle portions of crop canopies, recent moisture conditions may promote further development.  There have been a low number of recent wind trajectories from this area, cool and relatively dry Prairie weather conditions, and early stages of Prairie crop development.  Thus, as of May 21, 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 winter wheat.

5.  Access the full downloadable report.

Weather synopsis

Weather synopsis – This past week (May 8-15, 2019) the average temperature was approximately 1 °C cooler than normal (Fig. 1). The warmest temperatures were observed in AB and with conditions much cooler in SK and MB.  

This week, May 15-21, 2019, cool, dry conditions continued to occur across the prairies. Though temperatures are warming up, early growing season daily average temperatures continue to be cooler than normal. This past week the average temperature was approximately 2.5 °C cooler than normal (Fig. 2). The warmest temperatures were observed in central AB, southeast SK and southwest MB (Fig. 2).  

Figure 1.  Average Temperature (°C) across the Canadian prairies the past seven days (May 15-21, 2019).
Figure 2.  Average Temperature (°C) across the Canadian prairies the past 30 days (April 21-May 21, 2019).

Average 30 day temperatures were approximately 3 °C cooler than average (Fig. 3). Across the prairies, average temperatures (April 23 – May 20, 2019)  were 2 to -3 °C below normal with central SK having temperatures that were 3 to 4 °C cooler than average with well below average temperatures occurring in a large area of central SK. 

Figure 3.  Mean temperature differences from Normal across the Canadian prairies from April 23-May 20, 2019.
Image has not been reproduced in affiliation with, or with the endorsement of the 
Government of Canada and was retrieved (21May2019).  
Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

This week (May 15-21, 2019), the seven-day cumulative rainfall indicated that minimal rain was observed across large areas of SK (Fig. 4). Most locations reported less than 5 mm.  Wetter conditions were reported in a corridor between Lethbridge and Calgary AB. 

Figure 4. Cumulative precipitation observed the past seven days across the Canadian prairies (May 15-21, 2019).

Across the prairies, rainfall amounts for the past 30 days (April 21-May 21, 2019) have been approximately 50% of normal (Fig. 5).  Rainfall in southwest SK has increased.  Between Brandon MB and Lloydminster SK 30-day rainfall amounts are well below average (Fig. 5). Growing season rainfall (April 1 – May 21) amounts have been well below average for most of the prairies, particularly in west central SK and eastern regions of AB (Fig. 6).  For this growing season, almost all of the prairies have received rainfall that is 85 percent or less than average (Fig. 7).

Figure 5.  Cumulative precipitation observed the past 30 days across the Canadian prairies (April 21-May 21, 2019).
Figure 6.  Cumulative precipitation observed for the growing season across the Canadian prairies (April 1-May 21, 2019).
Figure 7. Percent of Average precipitation across the Canadian prairies for the growing season (April 1-May 21, 2019).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and 
was retrieved (21May2019).  
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. Near normal soil moisture is predicted to occur in an area extending from Swift Current, west to Lethbridge and north to Edmonton and Grande Prairie (Fig. 8).

Figure 8. Modeled soil moisture (%) across the Canadian prairies (up to May 21, 2019).

The growing degree day map (GDD) (Base 5 ºC, April 1-May 20, 2019) is below (Fig. 9):

Figure 9.  Growing degree day (Base 5 ºC) across the Canadian prairies for the growing season (April 1-May 20, 2019).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (22May2019).  
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-May 15, 2019) is below (Fig. 10):

Figure 10.  Growing degree day (Base 10 ºC) across the Canadian prairies for the growing season (April 1-May 20, 2019).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (22May2019).  
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 range from -10 to 2 °C in the map below (Fig. 11).

Figure 11.  Lowest temperatures (°C) observed across the Canadian prairies the past seven days (May 14-20, 2019).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (22May2019).  
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 range from -10 to 2 °C in the map below (Fig. 12).

Figure 12.  Highest temperatures (°C) observed across the Canadian prairies the past seven days (May 14-20, 2019).Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (22May2019).  
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 may wish to bookmark the AAFC Drought Watch Maps for the growing season.

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. 

Model output indicates that alfalfa weevil hatch has begun and first instar alfalfa weevils should be present across most of AB (Fig. 1). Model runs for Brooks AB (Fig. 2) and Swift Current SK (Fig. 3) were projected to June 15, 2019.  Second instar larvae will begin to occur late next week in fields near Brooks and 3-5 days later in the Swift Current region. 

Figure 1.  Predicted percent of grasshopper (Melanoplus sanguinipes) population at first instar stage across the Canadian prairies (as of May 21, 2019). 
Figure 2. Projected predicted status of alfalfa weevil populations near Brooks AB to June 15, 2019, using long term average temperatures.
Figure 3.  Projected predicted status of alfalfa weevil populations near Swift Current SK to June 15, 2019, using 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 AB (Fig. 1) and Swift Current SK (Fig. 2) were projected to June 15, 2019. Results indicated that oviposition should begin at the end of May. Model predictions, based on long term normal weather data, predict that initial hatch near Saskatoon should occur on May 29th.

Figure 1.  Projected predicted status of pea leaf weevil populations near Red Deer AB to June 15, 2019 using long term average temperatures.
Figure 2.  Projected predicted status of pea leaf weevil populations near Swift Current SK to June 15, 2019 using long term average temperatures.

Pea leaf weevils emerge in the spring primarily by flying (at temperatures above 17ºC) or they may walk short distances. Pea leaf weevil movement into peas and faba beans is achieved primarily through flight.  Adults are slender, greyish-brown measuring approximately 5 mm in length (Fig. 3, Left).  

The 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 3.  Comparison images and descriptions of four Sitona species adults including pea leaf weevil (Left).

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 leaf beetle

Cereal leaf beetle (Oulema melanopus) – The CLB model was run for Lethbridge AB (Fig. 1), Brandon MB (Fig. 2), and Grande Prairie AB (Fig. 3) and projected to June 15, 2019.  The cereal leaf beetle model indicates that eggs may begin to hatch later next week in Lethbridge (Fig. 1) and Brandon (Fig. 2). Hatch is predicted to be 4-7 days later in the Peace River region (Fig. 3).

Figure 1. Projected predicted status of cereal leaf beetle populations near Lethbridge AB to June 15, 2019, generated using long term average temperatures.
Figure 2. Projected predicted status of cereal leaf beetle populations near Brandon MB to June 15, 2019, generated using long term average temperatures.
Figure 3. Projected predicted status of cereal leaf beetle populations near Grande Prairie AB to June 15, 2019, generated using long term average temperatures.

Lifecycle and Damage:

Adult: Adult cereal leaf beetles (CLB) have shiny bluish-black wing-covers (Fig. 2). 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 2. 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. 3).  When the larva completes its growth, it drops to the ground and pupates in the soil. 

Figure 3.  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).  

As of May 21, 2019, predicted grasshopper egg development was 66% (63% last week) and is similar to long term average values (68%) (Fig. 1).  

Figure 1. Predicted grasshopper (Melanoplus sanguinipes) embryological development across the Canadian prairies as of May 21, 2019. 
Figure 2.  Predicted percent of grasshopper (Melanoplus sanguinipes) population at first instar stage across the Canadian prairies (as of May 21, 2019). 

Model runs for Grande Prairie (Fig. 3), Lethbridge (Fig. 4) and Saskatoon (Fig. 5) were projected to June 15, 2019.  Results for Lethbridge (Fig. 4) and Saskatoon (Fig. 5) indicated that eggs should begin to hatch this week. Hatch in the Peace River region is predicted to be approximately one week later. Results also indicated that initial hatch (less than 6%) should have occurred in southwest SK and southeast AB.

Figure 3.  Predicted status of Melanoplus sanguinipes populations near Grande Prairie AB as of  May 21, 2019.  
Figure 4.  Predicted status of Melanoplus sanguinipes populations near Lethbridge AB as of  May 21, 2019.  
Figure 5.  Predicted status of Melanoplus sanguinipes populations near Saskatoon SK as of  May 21, 2019.  

Reminder – The Prairie Pest Monitoring Network’s 2019 Grasshopper Forecast Map was released in March.  Review all the current risk and forecast maps by linking here.  While spring temperatures, soil moisture conditions, and precipitation can all have an impact on overwintered grasshopper eggs, areas highlighted orange or red in the 2019 forecast map should be vigilant this spring by performing in-field scouting to assess nymph densities.

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.

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 May 22, 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:

The following crop reports are also available:

Field Events – Speak to an entomologist

Public summer field events – Coming to a field near you –  Our 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 6, 2019. Farming Smarter crop walk or plot hop if you are a flea beetle! Access event information. Entomologist participating: Hector Carcamo

•  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 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.

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

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

Ticks and Lyme disease – Week 4

Weather Radar – Week 6

Wind trajectories – Weeks 1-4

Insect of the Week – Spotted wing drosophila (Drosophila suzukii Mats.)

(This week’s post is provided by Dr. James Tansey, Saskatchewan Ministry of Agriculture, Provincial Specialist, Insect/Vertebrate Pest Management)

With the onset of the 2019 growing season, we decided to feature an insect that is becoming a growing problem throughout Canada: Spotted Wing Drosophila (SWD), Drosophila suzukii.

Figure 1: Spotted wing drosophila (Drosophila suzukii) adults on raspberry fruit Hannah Burrack, North Carolina State University, Bugwood.org

This invasive insect is thought to have originated in southeast Asia. The first record of SWD is from Japan in 1916. SWD is now established in small and stone fruit production areas throughout North America. SWD has been reported in British Columbia since 2009, and was first reported in Alberta in 2010. Although it has not yet been found in Saskatchewan, occurrence in Alberta and low levels in southern Manitoba suggest that SK infestations are likely imminent. Saskatchewan Ministry of Agriculture will be monitoring for this pest this summer (2019).

SWD is an economic pest of many soft fruits including raspberry, strawberry, cherry, blueberry and plum (Figure 1). Saskatoon berry has been documented as a host. Haskap is also considered susceptible but may escape major damage as SWD populations typically do not increase until after harvest. However, Ontario haskap growers have seen economic losses when a mild winter is coupled with factors that lead to delayed ripening.

SWD adults are 3-4 mm, yellow-brown with red eyes. Males have a conspicuous spot on the leading edge of each wing (Figure 2). Females lack the spots but have a characteristic large, serrated ovipositor (Figure 3).

Figure 2: Spotted wing drosophila (Drosophila suzukii) adult male
cc by 2.0 – Martin Cooper
Figure 3: Spotted wing drosophila (Drosophila suzukii) adult female
cc by 2.0 – Martin Cooper

SWD overwinter as adults. These become active in the spring, mate and seek egg-laying sites. Female SWD lay as many as 16 eggs per day for up to two months, averaging 384 eggs each. Female SWD deposit eggs with their serrated ovipositor under the skin of healthy, ripening fruit. Oviposition sites look like pin-holes in the skin (Figure 4). These can also serve as avenues of entry to pathogens like brown rot and botrytis. Several larvae can occur per fruit (Figure 5). Larval feeding causes fruit to become prematurely soft and unmarketable. Larvae mature in 3-13 days and pupate most commonly in the fruit. The pupal stage lasts another 3-15 days. Multiple generations per year are common.

Figure 4: Ovipositor scars in cherry fruit from Spotted wing drosophila (Drosophila suzukii
cc by 3.0 – Martin Hauser Phycus
Figure 5: Spotted wing drosophila (Drosophila suzukii) larva
Hannah Burrack, North Carolina State University, Bugwood.org

Although SWD adults can be moved around by winds, movement of contaminated plant material is the major route for dispersal. Current management includes culling and destruction of soft fruit and the application of insecticides to established populations. Products registered to control SWD can be on Health Canada’s pesticide label search site (http://pr-rp.hc-sc.gc.ca/ls-re/index-eng.php). Use the search terms ‘spotted wing drosophila’. Product updates occur periodically so check this site regularly.

For information about previous featured insects, please visit our Insect of the Week page. For even more information on crop pests and their natural enemies, be sure to check out our newly updated Field Guide and Cutworm Guide, available for free download on our Insect Field Guide and Cutworm Field Guide pages.

Weather synopsis

Weather synopsis – This past week (June 11 – 18, 2018), the average temperature (12.4 °C) was 1 °C cooler than long term average values (Fig. 1). The warmest weekly temperatures occurred across Manitoba. The 30-day (May 19-June 18, 2018) average temperature (13.1 °C) was approximately 1 °C warmer than long term average (Fig. 2).  

Figure 1.  Weekly (June 11 – 18, 2018) average temperature (°C) . 
Figure 2.  The 30-day (May 19 – June 18, 2018) average temperature (°C).

Weekly and 30-day total precipitation was above average (Figs. 3 and 4).  The wettest (30-day) region was across eastern areas in SK and western MB, while western Saskatchewan and most of Alberta are dry.

Figure 3.  Weekly (June 11 – 18, 2018) cumulative precipitation (mm).
Figure 4.  The 30-day (May 19 – June 18, 2018) cumulative precipitation (mm).

Accumulated precipitation for the growing season (April 01-June 19, 2018) is available from Agriculture and Agri-Food Canada (Fig. 5).

Figure 5.  Precipitation across the Canadian prairies for the growing season (April 1-June 18, 2018). 
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (21Jun2018).  Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1529635048320).

The map below reflects the Highest Temperatures occurring over the past 7 days (June 5-11, 2018) across the prairies and is available from Agriculture and Agri-Food Canada (Fig. 6). 

Figure 6.  Highest temperature across the Canadian prairies the past seven days (June 13-19, 2018).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (21Jun2018).  Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1529635048320).

The map below reflects the Lowest Temperatures occurring over the past 7 days (June 5-11, 2018) across the prairies and is available from Agriculture and Agri-Food Canada (Fig. 7).

Figure 7.  Lowest temperature across the Canadian prairies the past seven days (June 13-19, 2018).
Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (21Jun2018).  Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1529635048320).

The growing degree day map (GDD) (Base 10ºC, March 1 – June 18, 2018) is below:

The growing degree day map (GDD) (Base 5ºC, March 1 – June 18, 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.

Weekly Update

Greetings!

Access the complete Weekly Update either as a series of Posts for Week 07 (June 21, 2018) OR a downloadable PDF version.  Also review the “Insect of the Week” for Week 7!

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!

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 June 18, 2018, the model output indicated that the average instar was 2.1 this week (1.7 last week), with 23, 27, 25, 8 and  2% in the 1st, 2nd, 3rd, 4th and 5th instar stages, respectively. The most rapid grasshopper development was predicted to occur across southern Manitoba and southeast Saskatchewan (Fig. 8).

Figure 8.  Grasshopper development (average instar) based on model simulations, for April 1 – June 18, 2018.

Model output for Saskatoon illustrates that populations are primarily in the 2nd and 3rd instar stages with 4th and 5th instar stages beginning to appear (Fig. 9). This agrees with this week’s survey conducted between Saskatoon and Rosetown. Melanoplinae adults were collected at a few sites near Saskatoon and eastern Saskatchewan.

Figure 9.  Predicted grasshopper phenology at Saskatoon SK.
Values are based on model simulations for April 1 – June 18, 2018.
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.

Predicted bertha armyworm development

Bertha armyworm (Lepidoptera: Mamestra configurata– BAW development continues to be 7-10 days ahead of normal development (Figs. 1 and 2). Near Saskatoon, oviposition is predicted to be well underway (Fig. 1). 

Figure 1.  Predicted bertha armyworm phenology at Saskatoon SK. 
Values are based on model simulations for April 1 – June 18, 2018.



Based on climate data (LTCN), oviposition near Saskatoon should begin the third week of June (Fig. 2).  

Figure 2.  Predicted bertha armyworm phenology at Saskatoon SK when using Long Term Climate Normal (LTCN) data.



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.  


Albertans can access the online reporting map (screenshot retrieved 19Jun2018 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.

Wheat midge

Wheat Midge (Sitodiplosis mosellana– Recent dry conditions near Saskatoon have resulted in slower wheat midge development (compared to last week’s model output).  Predictions for 2018 (Fig. 1) are similar to long term average values (Fig. 2). 

Figure 1.  Predicted wheat midge phenology at Saskatoon SK.
Values are based on model simulations for April 1 – June 18, 2018.




Figure 2.  Predicted wheat midge phenology at Saskatoon SK.
Values are based on model simulations for Long Term Climate Normals.

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. 



The 2018 wheat midge forecast map was circulated in January and is posted below for reference.  Note that areas highlighted orange or red in the map below included surveyed fields with comparatively higher densities of wheat midge cocoons last fall.


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.


Lygus in canola

Lygus bugs (Lygus spp.) – The model indicated that Lygus populations range between the 1st – 4th instar stages with the average being second instar stage.  The greatest development is predicted to occur across southern Manitoba and Saskatchewan (Fig. 1). The model suggests that Saskatoon populations consist of first to third instar stages (Fig. 2). 

Figure 1.  Lygus development (average instar) based on model simulations, for April 1 – June 18, 2018.




Figure 2.  Predicted Lygus phenology at Saskatoon SK. Values are based on model simulations for April 1 – June 18, 2018.





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.

Consider the estimated cost of spraying and expected return prior to making a decision to treat a crop. 

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.

Diamondback moth

Diamondback moth (Plutellidae: Plutella xylostella) – Once the diamondback moth is present in the area, it is important to monitor individual canola fields for larvae.  Warm growing conditions can quickly translate into multiple generations in a very short period!


Monitoring:

Remove the plants in an area measuring 0.1 m² (about 12″ square), beat them on to a clean surface and count the number of larvae (Fig. 1) dislodged from the plant. Repeat this procedure at least in five locations in the field to get an accurate count.


Figure 1. Diamondback larva measuring ~8mm long.
Note brown head capsule and forked appearance of prolegs on posterior.


Figure 2. Diamondback moth pupa within silken cocoon.


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  (approximately 1-2 larvae per plant).

Figure 3. Diamondback moth.


Across the prairies, provincial staffs coordinate diamondback pheromone trapping during the growing season.  Every spring, the early arrival of diamondback moths (Fig. 3) is monitored through the tracking of high level air masses that originate from the south of North America and arrive across the Canadian prairies. Additionally, pheromone traps are deployed to intercept the initial moths.  Cumulative male moth counts occurring over a 6-7 week period of trapping are used to estimate relative risk for the growing season.  Vast networks of cooperators across Manitoba, Saskatchewan, Alberta, and the BC Peace work with their provincial entomologists to generate the following in-season results: 



● Counts are summarized by Saskatchewan Agriculture (updated June 15, 2018, by J. Tansey):



● Manitoba Agriculture generally reports low DBM counts so far but review the specifics by region within the latest Insect and Disease Update (June 6, 2018).  


● Alberta Agriculture and Forestry has a live 2018 map reporting Diamondback moth pheromone trap interceptions.  A copy of the map (retrieved June 21, 2018) is below for reference.



Biological and monitoring information for DBM is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, and the Prairie Pest Monitoring Network.  

More information about Diamondback moths 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 Diamondback moth page but remember the guide is available as a free downloadable document as both an English-enhanced or French-enhanced version.

Cabbage seedpod weevil

Cabbage seedpod weevil (Ceutorhynchus obstrictus) –  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.




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.

Reminder – The 2017 cabbage seedpod weevil distribution map was circulated in January and is posted below for reference.  Note that areas highlighted orange or red in the map below included fields with comparatively higher densities of the weevil in 2017 so in-field scouting is particularly important in these same areas in 2018.




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

Request for Cereal Leaf Beetle Larvae

Researchers need your help – They are looking for LIVE cereal leaf beetle larvae from any field across the Canadian prairies in order to assess Tetrastichus julis parasitism rates.

If larvae are encountered in 2018, please carefully collect 20-30 of them and put them with some cereal leaves and a moist paper towel in a hard container (e.g. plastic yogurt container) with holes poked in the lid for air. Pack the parcel with ice packs, label with your name, date, crop type, and location, and send them to us.  Email or phone us for information on how to ship for free.

What’s in it for you? Learn if cereal leaf beetle is being controlled by natural enemies in your field. If you need T. julis, we may be able provide you with some.

Contact:
Dr. Haley Catton, Agriculture and Agri-Food Canada
5403 – 1 Ave S, Lethbridge, Alberta T1J 4B1
403-317-3404, haley.catton@canada.ca

Pea leaf weevil

Pea Leaf Weevil (Sitona lineatus– The PLW model predicted that larvae should be appearing in fields near Saskatoon (Fig. 1). Development in 2018 is faster than that predicted using long term averages  (LTCN presented in Fig. 2).  

Figure 1.  Predicted pea leaf weevil phenology at Saskatoon SK.
Values are based on model simulations for April 1 – June 18, 2018.
Figure 2.  Predicted pea leaf weevil phenology at Saskatoon SK. 
Values are based on model simulations for April 1 – June 18, 2018. using Long Term Climate Normals.



Larvae develop under the soil over a period of 30 to 60 days. They are “C” shaped with a dark brown head capsule. The rest of the body is a milky-white color (Fig. 3 A). Larvae develop through five instar stages. In the 5th instar, larvae range in length from 3.5 – 5.5 mm. First instar larvae bury into the soil after hatching, and search out root nodules on field pea and faba bean plants. Larvae enter and consume the microbial contents of the root nodules (Fig. 3 B). These root nodules are responsible for nitrogen-fixation, thus pea leaf weevil larval feeding can affect plant yield and the plant’s ability to input nitrogen into the soil. 

Figure 3.  Pea leaf weevil larva in soil (A) and field pea root nodules damaged by larval feeding (B).  Photos: 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 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.

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).

Field Heroes

What a difference a year makes! The Field Heroes campaign has been successful at raising awareness of the role of beneficial insects in Western Canadian crops. You’ll see this year’s campaign giving growers and agronomists more details on the many natural enemies they should be scouting for in cereal, oilseed and pulse crops.

Please make use of the Scouting Guides freely available on the Field Heroes website.  Each guide includes valuable information and photos to help identify the contents of a sweep-net and to increase understanding of the impact of beneficial insects. Please share and encourage use of the Scouting Guides.

Be sure to follow @FieldHeroes on Twitter for practical tips and information. Please tag @FieldHeroes in your own Tweets about beneficials. Re-Tweets are great, too.

Thanks to Western Grains Research Foundation for their support of this important campaign. This initiative is not possible without the support and advice of enthusiastic members of the Prairie Pest Monitoring Network. Our research is having a tangible impact on growers’ pest management decisions.

Link here to access a complete list of all the PPMN Blog Posts related to Natural Enemies!

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 Update for 2018 can be accessed here. Review the most recent update (June 6, 2018) prepared by John Gavloski and Holly Derksen. The insect update notes flea beetles in canola and cutworms with monitoring for alfalfa weevil larvae underway. Diamondback moth trap numbers remain low and bertha armyworm pheromone traps will go up this week.

Saskatchewan‘s Crop Production News for 2018 is now posted. Access Report #2 posted June 7, 2018. Insect monitoring information is included in the article, “Troubleshooting emergence and assessing plant stand densities in flax or canola“. Saskatchewan growers can review articles posted for flea beetles, pea leaf weevils. Also note the following updated diamondback moth pheromone trap interception counts from across the regions (updated June 15, 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 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.

Crop reports

Crop reports are produced by:
• Manitoba Agriculture (June 18, 2018)
• Saskatchewan Agriculture (June 12-18, 2018)
• Alberta Agriculture and Forestry Crop Report (June 12, 2018)

The following crop reports are also available:
• The United States Department of Agriculture (USDA) produces a Crop Progress Report (view the June 18, 2018 edition).

• The USDA’s Weekly Weather and Crop Bulletin (view the June 19, 2018 edition).

Monarch migration

We continue to track the migration of the Monarch butterflies as they move north by checking the 2018 Monarch Migration Map!  A screen shot of the map has been placed below as an example (retrieved 21Jun2018) but follow the hyperlink to check the interactive map.  They are in Manitoba and moving west through southern Saskatchewan this week!

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 fascinating insect.  

Previous Posts

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


Alfalfa weevil – Week 6

Cereal aphid manager (CAM) – Week 2
Cereal leaf beetle – Week 5
Crop protection guides – Week 2
Cutworms – Week 4

Flea beetles – Week 4

PMRA Pesticide Label Mobile App – Week 4

Scouting charts (canola and flax) – Week 3

Ticks and Lyme Disease – Week 4

Weather radar – Week 3
Wind trajectories – Week 6
Wireworm distribution maps – Week 6

Insect of the Week – Red turnip beetle (Entomoscelis americana)

This week’s Insect of the week is the red turnip beetle (Coleoptera: Chrysomelidae). This beetle is 7-10 millimeters long and has a distinctive red body with black markings on the head and thorax, and three black stripes down its back (elytra). They feed on mustards, canola, cole crops, and cruciferous weeds (except stinkweed).

They overwinter as reddish brown oval eggs in the soil. Adults emerge in the spring to feed for 2-3 weeks before re-entering the soil to escape the summer heat. When they re-emerge, they disperse throughout the host crop, feeding, mating, and laying eggs (300-400/female). Feeding damage can cause delayed harvest or need for re-seeding to replace killed plants. Later in the season they feed on leaves, stems, and pods. Attached pods are prone to premature shelling.

For more information about the red turnip beetle, have a look at our Insect of the Week page!

Red turnip beetle adult and damage
John Gavloski, Manitoba Agriculture, Food and Rural Development

Insect of the Week – Wheat midge

This week’s Insect of the Week is the wheat midge. Larvae feed on the surface of developing wheat kernels in spring and winter wheat, durum wheat, triticale and occasionally spring rye. Damage includes aborted, shrivelled, misshapen, cracked, or scared kernels. This lowers grain yield, quality and grade.

For more information on the wheat midge, visit our Insect of the Week page.

Wheat midge – larva (Mike Dolinski, MikeDolinski@hotmail.com

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

Weekly Update – Greetings!

Greetings!

Access the complete Weekly Update either as a series of Posts for Week 7 (Jun 15, 2017) OR downloadable PDF version.





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.

Subscribe to the Blog by following these easy steps!

Weekly Update – Weather Synopsis

Weather synopsis – Over this past week, average temperatures were similar to last week and only marginally cooler than long term averages for early June. Average temperatures were warmest in southern Manitoba with cooler conditions occurring across Alberta. 



 This second map presents the 30 Day Average Temperature. Average temperatures were greatest in southern regions of Manitoba and central Alberta.

The map below indicates that 7 Day Accumulated Precipitation was greatest across Alberta while central and southern Saskatchewan continued to be dry. 



The map below indicates that the rainfall amounts for the past month (May 13 – June 11) were average to above-average in Alberta and below-average for Manitoba and Saskatchewan.


The updated growing degree day map (GDD) (Base 5ºC, March 1 – June 11, 2017) is below:



While the growing degree day map (GDD) (Base 10ºC, March 1 – June 11, 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 Grasshopper Development

Grasshopper Simulation Model Output – Simulation modelling is used to predict grasshopper development across the prairies. Weekly temperature data is incorporated into the model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper). Predicted hatch for June 11, 2017, was 52% (23% last week) with 32% of the population in the first instar, 15% second instar and 15% third instar. 

The greatest development was predicted to be across southern regions in all three provinces, particularly southeastern Alberta and a region extending south from Swift Current/Regina to the US border. 



Grasshopper populations near Saskatoon were predicted to be primarily in the second instar with appearance of some third and fourth instars. This week’s survey (southwest of Saskatoon) agreed with model predictions with first collections of a few fourth instars.  





Model output for Grande Prairie indicates that development continues to be approximately 10 days later than locations across the southern prairies.

Reminder:  Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Food and Rural DevelopmentSaskatchewan 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.

Weekly Update – Predicted Bertha Armyworm Development

Bertha armyworm (Lepidoptera: Mamestra configurata– Emergence of adult moths is well underway. The map illustrates predicted appearance of adults (percent of the population) across the southern prairies; oviposition is predicted to begin this week with first hatch beginning later next week.

For those of you monitoring BAW pheromone traps, you may want to 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.

Weekly Update – Wheat midge

Wheat Midge (Sitodiplosis mosellana– The Insect of the Week features wheat midge!  


Simulation modelling is used to predict wheat midge emergence across the Canadian prairies.  The model predicted that wheat midge adults should emerge in July. The following graphs indicate that adult emergence at Saskatoon (Fig. 1) could be two weeks later than at Melfort (Fig. 2). Though average temperatures have been similar for both locations, model output indicates that dry conditions at Saskatoon (6 mm since June 1) may result in delayed emergence. Adequate moisture at Melfort (20 mm since June 1) has resulted in expected emergence patterns. Predicted rainfall for this week should result in emergence patterns that are more typical.

Figure 1. Predicted wheat midge development at Saskatoon SK.


Figure 2.  Predicted wheat midge development at Melfort SK.

As a refresher, the 2017 wheat midge forecast map circulated in January can be accessed at our Risk and Forecast Maps Post.  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.

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 – Pea leaf weevil

Pea Leaf Weevil (Sitona lineatus– Oviposition is predicted to have peaked across central and southern regions of Alberta and Saskatchewan.  Hatch should be underway in pea fields near Lethbridge while hatching is predicted to occur this week near Saskatoon. 

Biological and monitoring information related to pea leaf weevil in field crops is posted by the province of Alberta and a NEWLY UPDATED PPMN monitoring protocol is available!

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.

Weekly Update – Alfalfa weevil

Alfalfa Weevil (Hypera postica) – Recent warm weather has resulted in rapid alfalfa weevil development. Model output indicates that 98% of the hatch is complete (less than 80% last week). Larval populations should be predominantly in the second (35%) and third (46%) instars.

Alfalfa growers are encouraged to check the Alfalfa Weevil Fact Sheet prepared by Dr. Julie Soroka (AAFC-Saskatoon) and 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).  That guide is available in both a free English-enhanced or French-enhanced version.

Weekly Update – White grubs in field crops

Scarabaeidae – 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).


2017 Wind Trajectories

THE WEEK OF JUNE 15, 2017


Reverse trajectories (RT)
There were 139 reverse trajectories that were predicted to pass across Alberta and Saskatchewan from the Pacific Northwest between May 26 and June 8.  

Forward trajectories (FT) 
The following map indicates the origin of forward trajectories predicted to cross the prairies over the next five days. There have been an increased number of winds that have crossed the prairies from the southwest USA and Mexico since June 1.


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 for 2017 is prepared by John Gavloski and Pratisara Bajracharya the latest issue (Insect and Disease Update).

● Saskatchewan’s Crop Production News – 2017 – Issue #2 prepared by Scott Hartley and Danielle Stephens is now posted and includes the latest update on pea leaf weevil.

● Watch for Alberta Agriculture and Forestry’s Call of the Land and access the most recent Insect Update provided by Scott Meers.


Crop reports

Crop reports are produced by:
• Manitoba Agriculture, Rural Development (June 12, 2017)
• Saskatchewan Agriculture Crop Report (May 30-June 5, 2017)
• Alberta Agriculture and Forestry Crop Report (June 6, 2017)

Weekly Update – Previous Posts

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

Brood X Cicadas

Canola scouting chart

Crop protection guides
Cutworms

Diamondback moth

Flax scouting chart

Flea beetles

Iceberg reports


Lily leaf beetle



PMRA Pesticide Label Mobile App

Ticks and Lyme disease



Weather radar

Wind trajectories


Weekly Update – Weather Synopsis


Across the prairies, weather conditions were warmer and wetter than long term average values for the period of June 6-13, 2016The average temperature was 15°C and was approximately 2°C warmer than the previous week. 




This week’s rainfall was generally greater than long term average amounts. For the 30 day period of May 14-June 13,  conditions were cooler in Alberta compared to Saskatchewan and Manitoba.  The area extending from Swift Current to Regina and north to Saskatoon continues to be the warmest/driest region of the prairies. 





The map below reflects the Accumulated Precipitation for the Growing Season so far for the prairie provinces (i.e., April 1-June 14, 2016):


The map below reflects the Accumulated Precipitation the Past 7 Days for the prairie provinces (i.e., June 8-14, 2016):


Compared to last week, overnight temperatures were warmer the past 7 days.  The map below shows the Lowest Temperatures the Past 7 Days (June 8-14, 2016) across the prairies:

The map below shows the Highest Temperatures the Past 7 Days (June 8-14, 2016):

The updated growing degree day map (GDD) (Base 5ºC, March 1 – June 12, 2016) is below:

While the growing degree day map (GDD) (Base 10ºC, March 1 – June 12, 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 – Cutworms

Cutworms (Noctuidae) – Please refer to earlier cutworm posts describing scouting tips, monitoring protocols and fact sheets (including cutworm images plus action and economic thresholds).

For Manitobans….The  earlier Insect Update included great photos of dingy and redbacked cutworms plus monitoring tips including how to discern these two species from one another.  Reports of cutworm continued in the current Insect Update.

For Saskatchewanians…. Cutworms were again reported in the recent Saskatchewan Insect Report.

For Albertans….. Additional reports of cutworms have occurred throughout the province the past week!  If you find cutworms, please consider using the Alberta Pest Surveillance Network’s “2016 Cutworm Reporting Tool”.  Once data entry occurs, your growers can view the live 2016 cutworm map.

A screen shot of the live map has been retrieved (15Jun2016) below for your reference.



Weekly Update – Grasshoppers

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

Reminder – Weekly surveying conducted by AAFC-Saskatoon Staff on June 2, 2016, confirmed that Melanoplines were primarily first and second instar stages although a few third instar nymphs were collected.

The following image showing various stages of the clearwinged grasshopper 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.  

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.

Bertha Armyworm

Bertha armyworm (Lepidoptera: Mamestra configurataThose monitoring BAW pheromone traps may want to compare trap “catches” to the following reference photo kindly shared by Saskatchewan Agriculture below:

Provincial staff coordinate BAW pheromone trapping across the prairies and summarize cumulative counts in report or map formats:
● Saskatchewanians.… Watch for future Insect Reports.  
● Manitobans.…. Watch for future Insect and Disease Reports.  

● Albertans.…..  Refer to the live 2016 map reporting Bertha armyworm pheromone trap interceptions.  A copy of the map (retrieved June 15, 2016) is below for reference.

Weekly Update – Swede midge

Swede midge (Contarinia nasturtii)  – 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. 





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.

Weekly Update – Cabbage seedpod weevil

Cabbage seedpod weevil (Ceutorhynchus obstrictus) –  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.


They 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.


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.





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.


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

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 (June 8, 2016, prepared by John Gavloski and Pratisara Bajracharya).

– Saskatchewan’s Insect Report which contains a reminder for cutworms (Issue 3, prepared by Scott Hartley).
– Watch for Alberta Agriculture and Forestry’s Call of the Land for updates from Scott Meers  who recently gave a summary (posted on June 9, 2016).

Weekly Update – Previous Posts

The following is a list of previous 2016 Posts – click to review:
Canola scouting chart
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 7 (June 15, 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.  

Wind Trajectories

THE WEEK OF JUNE 13, 2016:  Wind trajectory data processing by AAFC-Saskatoon Staff began in April.  Reverse Trajectories track arriving air masses back to their point of origin while Forward Trajectories predict favourable winds expected to arrive across the Canadian Prairies for the week of  June 13, 2016:

Reverse trajectories (RT)
Mexico and southwest USA – This week, Grande Prairie (June 7) had the first report of a Reverse Trajectory crossing over southwest US and Mexico crossing. Other sites included Selkirk, Portage, Carman and Brandon.

The map below represents the distribution of RTs from the prairies that originated over southwest US and Mexico.


Forward trajectories (FT) 
There were 17 Forward Trajectories from southwest US (12) and Mexico (5) that were predicted to cross the prairies over the next five days.



Weather forecasts (7 day):
Winnipeg: https://weather.gc.ca/city/pages/mb-38_metric_e.html
Brandon: https://weather.gc.ca/city/pages/mb-52_metric_e.html
Saskatoon: https://weather.gc.ca/city/pages/sk-40_metric_e.html
Regina: https://weather.gc.ca/city/pages/sk-32_metric_e.html
Edmonton: https://weather.gc.ca/city/pages/ab-50_metric_e.html
Lethbridge: https://weather.gc.ca/city/pages/ab-30_metric_e.html
Grande Prairie: https://weather.gc.ca/city/pages/ab-31_metric_e.html


Downloadable versions of the Wind Trajectory Updates are available here.

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 12, 2016, thanks to D. Giffen for updating the following map to match the above predicted developmental stages and corresponding degree-days.  Areas highlighted yellow are predicted to find second instar larvae the week of June 12th.   Areas highlighted gold are predicted to encounter third instar larvae while areas highlighted orange should observe 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 syptoms 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 – Crop reports

Crop reports are produced by:

– Manitoba Agriculture, Rural Development (June 6, 2016)
– Saskatchewan Agriculture Crop Report (June 6, 2016)

– Alberta Agriculture and Forestry (for June 7, 2016)

Insect of the Week – Tetrastichus julis

Tetrastichus julis (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 Tetrastichus julis (sorry, no common name), an important cereal leaf beetle parasitoid. Where T. julis has become established, it can reduce cereal leaf beetle populations by 40 – 90%, preventing yield loss without using pesticides. See also the factsheet, Biological Control at its Best, Using the T. julis Wasp to Control the Cereal Leaf Beetle (French version).


For information about the cereal leaf beetle (p. 24) and other pests and their natural enemies, 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).

T. julis adult parasitizing a cereal leaf beetle larva 
– Swaroop Kher, University of Alberta/AAFC


Weekly Update (Update)

Today we updated the Bertha armyworm and Grasshopper sections of the Weekly Update that was originally posted on June 17, 2015!  

Please review either the Post (in HTML format) by scrolling down below and selecting it OR access a PDF copy of the updated file.

Insect of the Week – Lygus bugs

The lygus bug (Lygus spp.) is this week’s Insect of the Week (from the new Field Crop and Forage Pests and their Natural Enemies in Western Canada – Identification and Management Field Guide). 

Environment Canada’s weather radar and precipitation events

If your field is near one of Environment Canada’s radar
stations, you can access weather
radar maps
in video format which show the past 1hr OR 3hrs of precipitation
events.  These maps can help growers
review where and how much precipitation fell nearby.
We included screen shots of Environment Canada’s webpages
below and we added red text and arrows to help.

Predicted wheat midge emergence

The map below is
the first of the predicted emergence maps for the wheat midge for
the 2015 growing season.  Remember, wheat midge emergence and flight will also be affected by precipitation events and wind.  Even so, if you are hoping
to catch the very first wheat midge as they start to emerge, keep watching the map below for areas
that will be highlighted below as lime-green (i.e., 600-693 DD). 
Rain fell over
the past five days so watch for the updated map in the Weekly Update which
should be available by Thursday.