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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 23-29, 2022) average daily temperatures were significantly warmer than last week. The average temperature across the prairies was 1C warmer than normal (Fig. 1). Temperatures were warmest in an area extending from Saskatoon to Winnipeg.
Figure 1. Seven-day average temperature (°C) across the Canadian prairies for the period of May 23-29, 2022.
Weekly temperatures continue to be cooler in the Peace River region. Average 30-day temperatures (April 30-May 29, 2022) were similar to climate normal values (Figs. 2 and 4). Temperatures were warmer than normal across most of Alberta and western Saskatchewan. The growing season (April 1-May 29, 2022) has been cooler than average (Fig. 3; Table 1).
Figure 2. 30-day average temperature (°C) across the Canadian prairies for the period of April 30 to May 29, 2022.Figure 3. Growing season average temperature (°C) observed across the Canadian prairies for the period of April 1 to May 29, 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 29, 2022.Table 1. Growing season temperature and rainfall summary for specific locations across the Canadian prairies (April 1- May 29, 2022).
PRECIPITATION: Seven-day cumulative rainfall ranged between 0 and 67 mm with the highest rainfall amounts occurring across western Manitoba and eastern Saskatchewan (Fig. 5). Conditions continue to be dry across western Saskatchewan and most of Alberta with rainfall amounts that were generally 5 mm or less for the period of May 23-29.
Figure 5. Seven-day cumulative rainfall (mm) observed across the Canadian prairies for the period of May 23-29, 2022.
Rain (30-day accumulation) amounts have been well above average across the eastern prairies, particularly southeastern Manitoba; rain amounts have been below normal in Alberta and western Saskatchewan (Figs. 6 and 8).
Figure 6. 30-day cumulative rainfall (mm) observed across the Canadian prairies the past 30 days (April 30 to May 29, 2022).
Growing season rainfall for April 1-May 29, 2022 continues to be greatest across Manitoba and eastern Saskatchewan yet conditions have been well below normal across most of western Saskatchewan and Alberta (Fig. 7; Table 1).
Figure 7. Growing season cumulative rainfall (mm) observed across the Canadian prairies for the period of April 1 to May 29, 2022.Figure 8. Growing season cumulative rain anomaly (% if climate normals) observed across the Canadian prairies for the period of April 1-May 29, 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 29, 2022. Recent warmer temperatures have resulted in increased rates of egg development. Last week average development was 64 %. This week, average egg development is predicted to be 73 % with a range of 63-82 % (Fig. 1). In comparison, egg development based on long-term climate data is typically 70 % by this week of the growing season (Fig. 2). Cool conditions in Manitoba and the Peace River region continue to result in slower than average development rates in those areas. Across southern Alberta, the simulation indicates that egg development is similar to long-term average values.
Figure 1. Predicted grasshopper (Melanoplus sanguinipes) embryological development (%) across the Canadian prairies as of May 29, 2022.Figure 2. Long-term average predicted grasshopper (Melanoplus sanguinipes) embryological development (%) across the Canadian prairies as of May 29 based on climate normals data.
Hatch is progressing across southern Alberta and western Saskatchewan (Fig. 3). Last week, grasshopper hatchlings were collected in an area between Saskatoon and Kindersley. Southern Alberta and western Saskatchewan have received the least amount of rain during the growing season. Grasshopper risk can be greater when conditions are warm and dry.
Figure 3. Predicted grasshopper (Melanoplus sanguinipes) grasshopper hatch (%) across the Canadian prairies as of May 29, 2022.
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 initial hatch should be occurring across southern and central regions of Alberta and Saskatchewan. First and second instar larvae are predicted to appear in alfalfa fields near Medicine Hat.
The following graphs indicate, based on potential number of eggs, that development is marginally faster near Vauxhall, Alberta (Fig. 1), compared to Saskatoon, Saskatchewan (Fig. 2). Development is similar to long-term average values. The model predicts that first and second instar larval populations may peak over the next 10 days near these two locations.
Figure 1. Predicted status of alfalfa weevil (Hypera postica) populations near Vauxhall AB as of May 29, 2022.Figure 2. Predicted status of alfalfa weevil (Hypera postica) populations near Saskatoon SK as of May 29, 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.
Warmer conditions in southern Alberta and southwest Saskatchewan are expected to have resulted in more rapid development of CLB populations in those areas than in southern Manitoba. The model output suggests that CLB hatch should be occurring across southern Alberta and Saskatchewan (Figs. 1 and 2). As a result of cooler conditions, egg development is predicted to be delayed in southern Manitoba (Fig. 3). The simulation predicts that second instar larvae may occur next week in southern Alberta and then 7-10 days later across southern Manitoba.
Figure 1. Predicted status of cereal leaf beetle (Oulema melanopus) populations near Lethbridge AB as of May 29, 2022.Figure 2. Predicted status of cereal leaf beetle (Oulema melanopus) populations near Maple Creek SK as of May 29, 2022. Figure 3. Predicted status of cereal leaf beetle (Oulema melanopus) populations near Brandon MB as of May 29, 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.
When considering average versus in-season pupal development, the current 2022 development of overwintered BAW pupae is expected to be significantly delayed for the Peace River region, Manitoba, and southern and eastern regions of Saskatchewan (Fig. 1). Though somewhat delayed, development of BAW pupae in southern and central Alberta and western Saskatchewan will be similar to average.
We recommend BAW pheromone traps be placed in fields when pupal development is 75-80 % to ensure traps are deployed in advance of the emergence of adults. The weather forecast predicts normal temperatures for the next week. This should advance BAW development with rates becoming similar to long-term average values. Based on current runs, it is advisable that Alberta and Saskatchewan traps be placed in fields by the end of next week (June 6-10). Traps in MB and the Peace River region should be put out one (Manitoba) or two (Peace River region) weeks later.
Figure 1. Predicted bertha armyworm (Mamestra configurata) pupal development (%) across the Canadian prairies as of May 29, 2022.
Biological and monitoring information related to bertha armyworm in field crops is posted by the provinces of Manitoba, Saskatchewan, Alberta and the Prairie Pest Monitoring Network. Also, refer to the bertha armyworm pages within 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 crossing the prairies originated from the Pacific Northwest (Idaho, Oregon and Washington) (Fig. 1). Relative to previous weeks, this past week (May 24-30, 2022) there was a significant increase in the number of trajectories (PNW, OK/TX and NE/KS) that passed 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 1-30, 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 30, 2022.
b. Mexico and southwest USA (Texas, California) – This past week there have not been any reverse trajectories that originated 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 30, 2022.
c. Oklahoma and Texas – Since April 1, reverse trajectories were reported for Manitoba and eastern Saskatchewan (Fig. 4). This past week (May 24-30, 2022) there was an increase in the number of reverse trajectories that have crossed over southeastern Saskatchewan (Weyburn and Gainsborough) and Manitoba (Portage and Brandon) relative to previous weeks.
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 30, 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). This past week (May 24-30, 2022) there was an increase in the number of reverse trajectories that have crossed over eastern Saskatchewan and Manitoba relative to previous weeks.
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 30, 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) that were 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 30, 2022.
View historical PPMN wind trajectory reports by following this link which sorts the reports from most recent to oldest.
The Pests and Predators Field Guide is filled with helpful images for quick insect identification and plenty of tips to manage the pests AND natural enemies in your fields. Claim your free copy at http://fieldheroes.ca/fieldguide/ or download a free copy to arm your in-field scouting efforts!
Review the Sweep-net Video Series including: • How to sweep a field. Meghan Vankosky (Agriculture and Agri-Food Canada-Saskatoon). Published online 2020. • What’s in my sweep-net? Meghan Vankosky (Agriculture and Agri-Food Canada-Saskatoon). Published online 2020. • Why use a sweep-net? Meghan Vankosky (Agriculture and Agri-Food Canada-Saskatoon). Published online 2020.
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 June 1, 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 been found in 24 traps. Levels are generally very low, with the exception that some moderate counts have occurred in the Eastern region, particularly over the past two weeks. The highest cumulative trap count so far is 50 from a trap near Hadashville in the Eastern region” Review page 4 of the above report for greater detail and regional counts.
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. So far, low numbers of diamondback moth have been intercepted across the province. • Cutworm live monitoring map for AB – Cumulative counts arising from weekly data are available so refer to the Live Map. So far, no cutworms have been reported on the live map.
