Weekly Update (May 14, 2020; Wk 03) Otani, Weiss, Rounce, Trudel, Svendsen, Turkington, Olfert, Vankosky

A bit of sun, some snow, some rain, a bit too hot and still too cold in other areas - typical spring weather for our prairie producers!

This week the incredible team working to provide weather-related data for PPMN forecasting is coping with technical difficulties so several of the normal updates are not available but stay tuned!

Access information to support your in-field insect monitoring efforts in the complete Weekly Update either as a series of Posts for Week 3 OR  a downloadable PDF.

Stay Safe!

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.

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Weather synopsis

Weather synopsis –  Though still early, the 2020 growing season has been cooler and dryer than normal. It was a cool, wet weekend across most of the prairies (Fig. 1) with many locations experiencing rain, flurries, mixed precipitation, and/or snow (Fig. 4). 

This past week (May 5 - 11, 2020; Fig. 1), the average temperature was approximately 2 °C cooler than normal and the average 30-day temperature (April 12 – May 11; Fig. 2) was 1 °C less than climate normal values (Fig. 3). Warm conditions have been experienced in Alberta while Manitoba has had cooler temperatures. 

Figure 1. Observed average temperatures across the Canadian prairies for the past seven days (May 5-11, 2020).

Figure 2. Observed average temperatures across the Canadian prairies for the past 30 days (April 12-May 11, 2020).

Figure 3. Mean temperature difference from Normal (°C) observed across the Canadian prairies the
past 30 days (April 14-May 11, 2020).

Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (03Jun2020).  

Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209

Seven-day (Fig. 4) and 30-day cumulative rainfall amounts (Fig. 5) were minimal rain across large areas of all three provinces.  Almost the entire prairie region has experienced dryer than normal precipitation over the past 30 days (Fig. 6).

Figure 4. Observed cumulative precipitation across the Canadian prairies for the past seven days (May 5-11, 2020).

Figure 5. Observed cumulative precipitation across the Canadian prairies for the past 30 days (April 12-May 11, 2020).

Figure 6. Percent of average precipitation observed across the Canadian prairies for 
the past 30 days (as of May 11, 2020).

Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (07May2020).  
Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209

The growing degree day map (GDD) (Base 5 ºC, April 1-May 4, 2020) is below (Fig. 7):

Figure 7. Growing degree day map (Base 5 °C) observed across the Canadian prairies for 
the growing season (April 1-May 11, 2020).

Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (14May2020).  
Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209

The growing degree day map (GDD) (Base 10 ºC, April 1-May 4, 2020) is below (Fig. 8):

Figure 8. Growing degree day map (Base 10 °C) observed across the Canadian prairies for 
the growing season (April 1-May 11, 2020).

Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (14May2020).  
Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209

Figure 9. Lowest temperatures (°C) observed across the Canadian prairies the past seven days (May 5-11, 2020).

Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (14May2020).  

Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209

Figure 10. Highest temperatures (°C) observed across the Canadian prairies the past seven days (May 5-11, 2020).

Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (14May2020).  

Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209

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

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.

Access the 2020 Wind Trajectory Reports for the first WEEKLY REPORT (11 May 2020).

New - Review the DAILY REPORT (released 15May2020).

Cutworms

Cutworms (Noctuidae) – A field guide is available to help growers scout and manage Cutworms.  Cutworm Pest of Crops is available for free in either English or French and is posted on the Cutworm Field Guide page!  

Several species of cutworms can be present in fields (Refer to downloadable PDF below).  They range in colour from shiny opaque, to tan, to brownish-red with chevron patterning.  Cutworm biology, species information, plus monitoring recommendations are available in the Prairie Pest Monitoring Network’s Cutworm Monitoring Protocol.  Also refer to Manitoba Agriculture cutworm fact sheet which includes action and economic thresholds for cutworms in several crops. 

In the past, the Insect of the Week featured economically important species of cutworms and some of the important natural enemies that help regulate these pests:
     Glassy cutworm - Wk01 (May 07, 2018)
     Darksided cutworm - Wk02 (May 14, 2018)
     Pale western cutworm - Wk01 (May 1, 2017)
     Dingy cutworm - Wk04 (May 23, 2017)
     Cutworm natural enemies - Wk03 (21 May, 2018)

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

 

For Albertans..... If you find cutworms, please consider using the Alberta Pest Surveillance Network’s “2020 Cutworm Reporting Tool” then view the live 2020 cutworm map which will be updated daily.

Flea beetles

Flea Beetles (Chrysomelidae: Phyllotreta species) – Check the latest Canola Watch May 13, 2020 article describing flea beetles feeding on volunteers which also links to management tips for flea beetles in canola. 

As canola seedlings emerge, scout for flea beetle damage on cotyledons but also on the stem (Fig. 1, left).  Two species, Phyllotreta striolata (Fig. 1, right) and P. cruciferae, will feed on all cruciferous plants but they can cause economic levels of damage in canola seedlings.  

Figure 1.  Flea beetle feeding on leaves canola seedling resulting in "shot-hole" damage plus girdling of stem (left) plus dorsal view of striped flea beetle (right).

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

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

Figure 1. Canola cotyledons with various percentages of leaf area consume owing to 
flea beetle feeding damage (Photo: Soroka & Underwood, AAFC-Saskatoon).

Figure 2.  Percent leaf area consumed by flea beetles feeding on canola seedlings 
(Photo: Soroka & Underwood, AAFC-Saskatoon).

Refer to the flea beetle page within the "Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide" (Philip et al. 2018) as an English-enhanced or French-enhanced version.

Diamondback moth

Diamondback moth (Plutellidae: Plutella xylostella) - Once 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!

Early season detection of diamondback moth is improved through the use of pheromone-baited delta traps deployed in fields across the Canadian prairies.  As they become available, moth reporting numbers observed in Alberta, Saskatchewan and Manitoba (not yet available) will be linked here.

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

Figure 3. Diamondback moth.

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

More information about Diamondback moths can be found by accessing the pages from the  "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.

Alfalfa weevil

Alfalfa Weevil (Hypera postica) – As a result of warmer temperatures in Saskatchewan (compared to Manitoba), AAW development is predicted to be greater in Saskatchewan.  The following graphs indicate, based on potential number of eggs (red line), that development is more advanced near Saskatoon (Fig. 1) than Brandon (Fig. 2).

Figure 1. Predicted alfalfa weevil (Hypera postica) phenology at Saskatoon SK.
Values are based on model simulations (April 1-May 11, 2020).

Figure 2. Predicted alfalfa weevil (Hypera postica) phenology at Brandon MB.
Values are based on model simulations (April 1-May 11, 2020).

 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. 2018). The guide is available as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – As of this week, average embryonic development is 62% (59.5% last week).  Development continues to be greatest across Saskatchewan and Alberta (Table 1; Fig. 1).

Table 1. Predicted percent embryonic development of Melanoplus sanguinipes populations at selected sites across the Canadian prairies (as of May 11, 2020).

Figure 1. Grasshopper embryological development (%) based on model simulations using
current environmental conditions (as of May 11, 2020).

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Saskatchewan Agriculture, Alberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network (newly updated). Also refer to the grasshopper pages within the "Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide" (Philip et al. 2018) as an English-enhanced or French-enhanced version.

Cereal leaf beetle

Cereal leaf beetle (Oulema melanopus) - The cereal leaf beetle model indicates that overwintered adults are active and  oviposition is underway across the prairies. The graphs provide a comparison of development for  Brandon (Fig. 1) and Lethbridge (Fig. 2). Reproductive adults appeared earlier in southern AB, resulting in earlier oviposition.

Figure 1. Predicted cereal leaf beetle phenology at Brandon MB.
Values are based on model simulations (April 1-May 11, 2020).

Figure 2. Predicted cereal leaf beetle phenology at Lethbridge AB.
Values are based on model simulations (April 1-May 11, 2020).

NEW for Manitobans - Dr. John Gavloski is looking for samples of cereal leaf beetle larvae this growing season to determine their range across Manitoba, their population density, and the rate at which larvae are parasitized. Please contact John (John.Gavloski@gov.mb.ca) or @JohnTheBugGuy if you observe cereal leaf beetles in your fields. 

Fact sheets for CLB are published by the province of Alberta and available from the Prairie Pest Monitoring Network. Also access the Oulema melanopus page from the "Field crop and forage pests and their natural enemies in western Canada - Identification and management field guide" available as a free downloadable document in either an English-enhanced or French-enhanced version.

Spring threshing surprise - Seeking beetle data please!

Large numbers of adult Amara ground beetles are being reported this spring (Fig. 1) in canola fields left unharvested last fall. These are non-pest beetles.  Adults feed on seeds, particularly those of cruciferous plants.  Larvae eat pest insects (e.g., grasshopper eggs).

Figure 1. An aggregation of Amara littoralis near Pickardville, AB. This was one of several outbreaks of
carabids observed in central Alberta in the autumn of 2010.  Photo B. Berry.

View another image of this beetle species at Bug Guide.  More images and life history information is available online at the Royal Alberta Museum or read this published Scientific Note by Floate and Spence (2015) describing previous reports of this species.

High numbers of these beetles may be due to an abundance of canola seed left on the ground last fall, which would have provided an ample food supply for adults going in the winter.  These overwintered adults have now emerged and are active.  They will lay their eggs in the soil during the next few weeks with their adult progeny emerging in late summer, which may generate more reports of their high abundance.

Dr. Kevin Floate (AAFC-Lethbridge) is interested in studying this phenomenon. If you observe an ‘outbreak’ of ground beetles, Dr. Floate is looking for the following information:
1. General location
2. 30 to 50 adult beetles collected from the ‘outbreak’ for identification (these can be stored in a small jar of rubbing alcohol)
3. Cropping history of the field where the ‘outbreak’ was observed, going back at least 2 years
4. The scope of the ‘outbreak’ (i.e. the number of acres affected), and
5. An estimate of beetle density (e.g., best guess of number of beetles per m2 or high resolution pictures of the outbreak)

Please contact Dr. Floate directly (kevin.floate@canada.ca) if you have observed a ground beetle ‘outbreak’ and are able to share information.

Thank you!

Field Heroes

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

New this week - Real Agriculture went live with a weekly Pest and Predators podcast series!
• Access Episode 1 - Do you know your field heroes?

New for 2020 - Check out the new Field Heroes YouTube video series:
• How to sweep a field
• What's in my sweep net
• Why use a sweep net

Access the Field Heroes Crop Scouting Guides - information on beneficial insects commonly occurring in Cereals, Oilseeds and Pulse Crops.  There are Pest Scouting Guides applicable to Cutworms, Aphids, Diamondback moth, and Bertha armyworm PLUS the common arthropod predators and parasitoids that attack them.  Also check out the Sweep Net Scouting Tips in the form of Cereal Avengers, Oilseed Avengers or Pulse Avengers.  Download or print them all to share!

Be sure to follow @FieldHeroes for practical tips and information.

Thanks to Western Grains Research Foundation for supporting this important campaign made possible by the support and advice of enthusiastic members of the Prairie Pest Monitoring Network.

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

Scouting Charts - Canola and Flax

Click here to access TWO generalized insect pest scouting charts (with hyperlinks to the insect guide) intended to aid in-field scouting on the Canadian prairies.

Provincial Insect Pest Reports

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

• Manitoba's Crop Pest Updates for 2020 are not yet available but are anticipated to live online here.

• Saskatchewan's Crops Blog Posts can include insect pest information. Also plan to access Crop Production News this growing season.

•  Alberta Agriculture and Forestry's Agri-News occasionally includes insect-related information.

Prairie Crop Disease Monitoring Network - Turkington

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

The PCDMN will release a series of weekly Cereal Rust Risk Reports throughout May and June.  Read the OVERVIEW describing the collaborative nature of this effort and the methods employed.  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.

Synopsis for May 5-11, 2020 - Wind trajectory and cereal rust risk assessment and need for in-crop scouting in the Prairie region

1. Pacific Northwest (PNW) – Even though there were a number of reverse wind trajectories that passed over the PNW region and into the prairies, given limited stripe rust development in the PNW, cool Prairie weather conditions, and early stages of Prairie crop development, as of May 11, 2020, the risk of stripe rust appearance from the PNW is limited and scouting for this disease is not urgent. 

2. Texas-Nebraska corridor – Given limited leaf and stripe rust development in this corridor, a relatively low number of recent wind trajectories from this area, cool Prairie weather conditions, and early stages of Prairie crop development, as of May 11, 2020 the risk of leaf and stripe rust appearance from the Texas-Nebraska corridor is limited and scouting for these diseases is not urgent.

3. Where farmers or consultants noticed stripe rust development on winter wheat in the fall of 2019, 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.

4. Read the full report here.  

Crop reports

Click the provincial ministry name below to link to online crop reports produced by:
• Manitoba Agriculture - Other viewing options include subscribing to receive or access a PDF of May 12, 2020 report.
• Saskatchewan Agriculture  or access a PDF of May 11, 2020 report.
• Alberta Agriculture and Forestry or access a PDF of May 5, 2020 report (released 08May2020).

The following crop reports are also available:
• The United States Department of Agriculture (USDA) produces a Crop Progress Report (read the May 11, 2020 edition).

• The USDA's Weekly Weather and Crop Bulletin (read the May 12, 2020 edition). 

Previous posts

Click to review these earlier 2020 Posts:

2019-2020 Risk and forecast maps

Bookmark prairie provincial insect pest pages (Wk02)

Crop protection guides (Wk02)

Insect Pest of the Week and the Entomologists that Study Them (May 11): Wheat pests / featuring Dr. Meghan Vankosky

This week's Insect of the Week feature crop is wheat (durum, spring and winter) and Dr. Meghan Vankosky is our starring entomologist.

Wheat stem sawfly (image courtesy Frank Peairs, wiki.bugwood.org)

Note: 

This year, we're doing things a bit differently for our Insect of the Week. Instead of focussing on a single insect (pest or natural enemy), we're looking at it from a crop perspective. Each week, we'll pick a crop and list the insects that attack it along with additional helpful information. The insect list is based on the information found in the Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and Management field guide. The field guide offers information describing lifecycle, damage description, monitoring/scouting strategies, economic thresholds (where available) and control options) for each economic pest.

In addition to an Insect of the Week, we'll also feature one of the entomologists that help support the PPMN, either directly or indirectly.