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!
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.
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).
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).
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).
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).
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.
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.
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.
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.
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).
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).
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.
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).
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.
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.