The weather report is a bit longer than usual owing to unusual conditions summarized broadly as cool and wet in the east, cool and dry in the west, and cool and wet in the Peace River region! This all has an impact on the progression of insect development as well as crop growth.
Catch Monday’s Insect of the Weekfor Week 3- it’s the most common wireworm, Hypnoidus bicolor!
Questions or problems accessing the contents of this Weekly Update? Please contact us so we can connect you to our information. Past “Weekly Updates” can be accessed on our Weekly Update page.
TEMPERATURE: Since April 1, the 2022 growing season has been cooler than normal, particularly across Manitoba. Conditions continue to be dry across Alberta and western Saskatchewan while rainfall amounts have been well above normal for eastern Saskatchewan and Manitoba. This past week (May 16-22, 2022), the average temperature across the prairies was 2 °C cooler than normal (Fig. 1). Temperatures were warmest in an area extending from Regina to Lethbridge and north to Edmonton.
Figure 1. Seven-day average temperature (°C) across the Canadian prairies for the period of May 16-22, 2022.
The average 30-day temperature (April 23-May 22, 2022) was 0.5 °C less than climate normal values (Fig. 2) and the growing season (April 1-May 22, 2022) has been 1.7 °C cooler than average (Fig. 3). Compared with climate normal values or average growing season temperatures, temperatures in 2022 have been 2-4 °C cooler than average across southeastern Saskatchewan and Manitoba (Fig. 4; Table 1).
Figure 2. 30-day average temperature (°C) across the Canadian prairies for the period of April 23 to May 22, 2022.Figure 3. Growing season average temperature (°C) observed across the Canadian prairies for the period of April 1 to May 22, 2022.Figure 4. Growing season average temperature anomaly (°C difference from climate normals) observed across the Canadian prairies for the period of April 1-May 22, 2022.Table 1. Growing season temperature and rainfall summary for specific locations across the Canadian prairies (April 1- May 22, 2022).
PRECIPITATION: Seven-day cumulative rainfall ranged between 0 and 54 mm with highest rainfall amounts occurring across Manitoba and the Parkland region of Saskatchewan (Fig. 5).
Figure 5. Seven-day cumulative rainfall (mm) observed across the Canadian prairies for the period of May 16-22, 2022.
Western Saskatchewan and most of Alberta have received little or no rain over the past seven days. Rain (30-day accumulation) amounts have been well above average across the eastern prairies, particularly southeastern Manitoba; rain amounts have been minimal in Alberta and western Saskatchewan (Fig. 6).
Figure 6. 30-day cumulative rainfall (mm) observed across the Canadian prairies the past 30 days (April 23 to May 22, 2022).
Growing season rainfall for April 1-May 22, 2022 has been greatest across Manitoba and eastern Saskatchewan; precipitation has been well below normal across most of Saskatchewan and Alberta (Figs. 7 and 8; Table 1).
Figure 7. Growing season cumulative rainfall (mm) observed across the Canadian prairies for the period of April 1 to May 22, 2022.Figure 8. Growing season cumulative rain anomaly (% if climate normals) observed across the Canadian prairies for the period of April 1-May 22, 2022.
The grasshopper (Acrididae: Melanoplus sanguinipes) model predicts development using biological parameters known for the pest species and environmental data observed across the Canadian prairies on a daily basis. Review lifecycle and damage information for this pest. Review the historical grasshopper maps based on late-summer adult in-field counts performed across the prairies.
Model simulations were used to estimate percent grasshopper embryonic (egg) development as of May 22, 2022. Egg development ranges between 55 and 75% across most of the prairies (average=64%) (Fig. 1). Based on climate normals data, long term average development should be 64% (Fig. 2). Cool conditions in Manitoba and the Peace River region continue to result in slower than average development rates. Across southern Alberta, the simulation indicates that egg development is similar to average values. This region has had the least amount of rain during the growing season.
Grasshopper risk can be greater when conditions are warm and dry. Initial hatch is predicted to have begun near Medicine Hat and Brooks Alberta.
Figure 1. Predicted grasshopper (Melanoplus sanguinipes) embryological development across the Canadian prairies as of May 22, 2022.Figure 2. Long-term average predicted grasshopper (Melanoplus sanguinipes) embryological development across the Canadian prairies as of May 22 based on climate normals data.
The alfalfa weevil (AAW) (Curculionidae: Hypera postica) model predicts development using biological parameters known for the pest species and environmental data observed across the Canadian prairies on a daily basis. Review lifecycle and damage information for this pest.
Model simulations for alfalfa weevil (AAW) indicate thatoviposition should be well underway across the prairies. The following graphs indicate, based on potential number of eggs, that development is marginally slower near Lethbridge, Alberta (Fig. 1) than Saskatoon, Saskatchewan (Fig. 2). The model predicts that hatch should begin next week.
Figure 1. Predicted status of alfalfa weevil (Hypera postica) populations near Lethbridge AB as of May 22, 2022.Figure 2. Predicted status of alfalfa weevil (Hypera postica) populations near Saskatoon SK as of May 22, 2022.
Additional information can be accessed by reviewing the Alfalfa Weevil Page extracted from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible as a free downloadable PDF in either English or French on our new Field Guides page.
The cereal leaf beetle (CLB) (Chysomelidae: Oulema melanopus) model predicts larval development using biological parameters known for the pest species and environmental data observed across the Canadian prairies on a daily basis. Review lifecycle and damage information for this pest.
Cereal leaf beetle (CLB) model output suggests that oviposition is underway across the southern prairies. The following graphs provide a comparison of development for Lethbridge, Alberta (Fig. 1) and Brandon, Manitoba (Fig. 2). Warmer conditions in southern Alberta are predicted to result in more rapid development of CLB populations than for southern Manitoba. The simulation predicts that first instar larvae may occur next week in southern Alberta and 7-10 days later across southern Manitoba.
Figure 1. Predicted status of cereal leaf beetle (Oulema melanopus) populations near Lethbridge AB as of May 22, 2022.Figure 2. Predicted status of cereal leaf beetle (Oulema melanopus) populations near Brandon MB as of May 22, 2022.
Access scouting tips for cereal leaf beetle or find more detailed information by accessing the Oulema melanopus page from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (2018; accessible as a free downloadable PDF in either English or French on our new Field Guides page.
1. REVERSE TRAJECTORIES (RT) Since May 1, 2022, the majority of reverse trajectories that have crossed the prairies originated from the Pacific Northwest (Idaho, Oregon and Washington) (Fig. 1). Relative to previous weeks, this past week (May 17-23, 2022) there were fewer trajectories passing over the prairies.
Figure 1. Average number (based on a 5-day running average) of reverse trajectories (RT) crossing the prairies for the period of May 1-23, 2022.
a. Pacific Northwest (Idaho, Oregon, Washington) – The majority of Pacific Northwest reverse trajectories have been reported to pass over southern and central Alberta and western Saskatchewan (Fig. 2).
Figure 2. Total number of dates with reverse trajectories originating over the Idaho, Oregon, and Washington that have crossed the prairies between April 1 and May 23, 2022.
b. Mexico and southwest USA (Texas, California) – This past week there were no reverse trajectories originating from Mexico, California or Texas. Since April 1, reverse trajectories were reported for Manitoba (Portage, Selkirk, Brandon, Carman, Russell) and eastern Saskatchewan (Gainsborough, Grenfell) (Fig. 3).
Figure 3. The total number of dates with reverse trajectories originating over Mexico, California and Texas that have crossed the prairies between April 1 and May 23, 2022.
c. Oklahoma and Texas – Since April 1, reverse trajectories were reported for Manitoba and eastern Saskatchewan (Fig. 4). No trajectories were predicted for May 17-23, 2022.
Figure 4. The total number of dates with reverse trajectories originating over Texas and Oklahoma that have crossed the prairies between May 1 and May 23, 2022.
d. Nebraska and Kansas – Reverse trajectories, originating from Kansas and Nebraska have crossed southeastern Saskatchewan and southern Manitoba (April 1 – May 23, 2022) (Fig. 5).
Figure 5. The total number of dates with reverse trajectories originating over Kansas and Nebraska that have crossed the prairies between April 1 and May 23, 2022.
2. FORWARD TRAJECTORIES (FT) The following map presents the total number of dates (since April 1, 2022) with forward trajectories (originating from Mexico and USA) predicted to cross the Canadian prairies (Fig. 6). Results indicate that the greatest number of forward trajectories entering the prairies have originated from the Pacific Northwest (Idaho, Oregon, Washington), Montana and Wyoming.
Figure 6. Total number of dates with forward trajectories, originating from various regions of the United States and Mexico, crossing the prairies between April 1 and May 23, 2022.
Provincial entomologists provide insect pest updates throughout the growing season so link to their information:
MANITOBA’SCrop Pest Updates for 2022 are up and running! Access a PDF copy of the May 25, 2022 issue here. Bookmark their Crop Pest Update Index to readily access these reports and also bookmark their insect pest homepage to access fact sheets and more! • Diamondback moth pheromone trap monitoring update for MB – “So far, diamondback moth has only been found in 14 traps.” Review page 5 of the above report for greater detail.
ALBERTA’SInsect Pest Monitoring Network webpage links to insect survey maps, live feed maps, insect trap set-up videos, and more. There is also a Major Crops Insect webpage. The new webpage does not replace the Insect Pest Monitoring Network page. Remember, AAF’s Agri-News occasionally includes insect-related information. Twitter users can connect to #ABBugChat Wednesdays at 10:00 am. • Diamondback moth pheromone trap monitoring update for AB – Cumulative counts arising from weekly data are available so refer to the Live Map. • Cutworm live monitoring map for AB – Cumulative counts arising from weekly data are available so refer to the Live Map.
