Weekly Update – Weather synopsis

Ross Weiss, Owen Olfert, David Giffen and Erl Svendsen
Week 2

Across the prairies, meteorological conditions for the period of May 1-8, 2016, continued to be warm and dry. 

The average temperature was 12.2 C and was 5 C warmer than the average temperature for May 1-8. 

This past week rainfall amounts were well below normal. Average rainfall (prairie wide) was less than 1 mm. 

Normal weekly rainfall is 8.7 mm. Rainfall amounts for the past 30 days (average =21 mm) were also below average (average= 28 mm). 

Compared to last week, soil moisture levels were predicted to be lower.

The map below reflects the Highest Temperatures occurring over the past 7 days across the prairies.

The map below reflects the Lowest Temperatures occurring over the past 7 days across the prairies.

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.

Wind trajectories

Ross Weiss, Owen Olfert, Serge Trudel and prairiepest_admin
Week 2
2016 Wind Trajectories – High altitude air masses originate from southern locations and continuously move northerly to Canadian destinations. Insect pest species such as Diamondback moth and Aster leafhoppers, traditionally unable to overwinter above the 49th parallel, can utilize these air masses in the spring to move north from Mexico and the United States (southern or Pacific northwest). Data acquired from Environment Canada is compiled by Olfert et al. (AAFC-Saskatoon) to track and model spring high altitude air masses with respect to potential introductions of insect pests onto the Canadian prairies. 

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.

As of May 9, 2016, Reverse Trajectories (RTs) originating from Mexico and southwest USA have crossed most prairie locations:

Whereas Reverse Trajectories (RTs) originating from northwest USA have arrived over a greater area of the prairies with more RTs arriving in Alberta and the BC Peace:

Review the 2016 Wind Trajectory Updates in PDF format.

Weather forecasts (7 day):

Weekly Update – Flea beetles

Jennifer Otani
Week 2

Flea Beetles (Chrysomelidae: Phyllotreta species) – Be on the lookout for flea beetle damage resulting from feeding on canola cotyledons but also on the stem.

Remember, the Action Threshold for flea beetles on canola is 25% of cotyledon leaf area consumed.  Shot-hole feeding is the traditional damage in seedling canola but watch the growing point and stems of seedlings.

Refer to the flea beetle page from 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 – Cutworms

Jennifer Otani, Scott Meers and John Gavloski
Week 2

Cutworms (Noctuidae) – Keep an eye on 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.  

Several species of cutworms  can be present in fields.  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 and Rural Initiatives cutworm fact sheet which includes action and economic thresholds for cutworms in several crops. 

More information about cutworms 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”.  An excerpt of ONLY Cutworm pages from 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.

For ALBERTANS….. If cutworms are spotted in Albertan fields, 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 (10May2016) below for your reference.

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

Weekly Update – Cereal leaf beetle predictions

Ross Weiss, David Giffen, Owen Olfert, Erl Svendsen and Jennifer Otani
Week 2

Cereal leaf beetle (Oulema melanopus) – Based on last week’s warm weather, our bioclimate model predicted rapid development of cereal leaf beetle (CLB) populations.

As of May 8, 2016, model indicated that oviposition is well underway and that larvae should be appearing across southern Alberta and a week later in southern Saskatchewan. Larval populations are predicted to peak in mid-June in southern Alberta and one to two weeks later at the Saskatchewan and Manitoba locations.

Predicted dates of peak emergence of CLB eggs and larvae:

Output suggests that it’s parasitoid, Tetrastichus julis, should be emerging during the period when CLB eggs are most abundant. The model run for Swan River MB showed potential symmetry for both species, though phenologies would be two weeks later than for southern Alberta.


Fact sheets for CLB are published by the province of Alberta and by the Prairie Pest Monitoring Network. Also access the Oulema melanopus page from the new “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide”.

Weekly Update – Predicted Grasshopper Development

Jennifer Otani, David Giffen, Owen Olfert, Ross Weiss and Erl Svendsen
Week 2

Grasshoppers (Acrididae) – Warm conditions over the past seven days have resulted in rapid grasshopper development. Predicted mean embryological development was 74% (last week was 62%) with greatest development predicted to be in southern AB. Embryological development is predicted to be 16% ahead of long term average values (prairie wide). The model predicts that 4% of the hatch is complete (AB, SK and MB).

Recall that the 2016 Grasshopper Forecast Map circulated in January predicted the following risk areas.  

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

Weekly Update – Crop reports

Scott Meers, Scott Hartley, John Gavloski and prairiepest_admin
Week 2

Crop reports are produced by:

International reports are produced by:

Weekly Update – Pea leaf weevil

Jennifer Otani
Week 2

Pea Leaf Weevil (Sitona lineatus) – 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.  

The pea leaf weevil resembles the sweet clover weevil (Sitona cylindricollis) yet the former is distinguished by three light-coloured stripes extending length-wise down thorax and sometimes the abdomen (Access the Pea leaf weevil monitoring protocol).  All species of Sitona, including the pea leaf weevil, have a short snout.  

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.

Information related to Pea leaf weevil in Alberta and the forecast for 2016 is posted here.