Released July 5, 2024

Welcome to Week 9 for the 2024 growing season! This week includes:
• Weather synopsis
• Wheat midge
• Grasshopper
• Diamondback moth
• Cabbage seedpod weevil
• Alfalfa weevil
• Bertha armyworm
• Cereal leaf beetle
• True armyworm
• West nile virus
• Monarch migration
• Provincial insect pest report links
• Crop report links
• Previous posts

Catch Monday’s Insect of the Week for Week 9 – What’s eating my crop? Wheat midge

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Weather synopsis

This week’s weather summary was kindly provided by the Prairie Crop Disease Monitoring Network (PCDMN).

Last week (Jun 24-30, 2024), a number of locations had 7 day rainfall amounts that exceeded 50 mm. Most of the rain was observed across the central prairies extending from Oyen to Brandon. Beaverlodge and Grande Prairie had rain amounts that exceeded 45 mm. Growing season temperatures have been similar to climate normal values while rainfall amounts continue to be well above average. Manitoba continues to have warm temperatures and above normal precipitation.

The average 30 day temperature (June 1 – 30, 2024) was 13.9 °C and was almost 1 °C cooler than long term average temperatures. Warmest temperatures were observed across Manitoba and the southern prairies (Figure 1). Most of the prairies have reported 30 day rainfall amounts were normal to above normal. Average cumulative rainfall (mm) over the past 30 days was 86 mm (71 mm last week) and was 150 % of climate normal values. Rainfall amounts have been greatest for Manitoba as well as central and Parkland regions of Saskatchewan (Figure 2). Rain amounts for the area extending from Saskatoon to Kindersley has been 250 % of normal for the past 30 days while cumulative 30 day rain totals for southwestern Saskatchewan and southern Alberta have been less than 65 % of normal.

Figure 1. 30 day average temperature (°C) observed across the Canadian prairies for the period of June 1-30, 2024.
Figure 2. 30 day cumulative rainfall (mm) observed across the Canadian prairies for the period of June 1-30, 2024.

Since April 1, the 2024 growing season average temperature (10 °C) has been marginally greater than climate normal values. Warmest average temperatures were observed across a region extending from Winnipeg to Saskatoon and southwest to Lethbridge (Figure 3). Growing season rainfall (prairie wide average) was 194 mm and has been above normal across most of the prairies (Figure 4). Regions around Brandon and Saskatoon have been particularly wet. Near normal precipitation amounts occurred across southern Saskatchewan, western Alberta and western areas of the Peace River region. Current rain amounts have been 175 % of climate normals. Cumulative rainfall has been lowest for a large region than is west of a line that extends from Regina to Grande Prairie (Figure 5).

Figure 3. Growing season average temperature difference from climate normal (°C) observed across the Canadian prairies for the period of April 1 – June 30, 2024.
Figure 4. Growing season percent of normal rain (%) observed across the Canadian prairies from April 1 to June 30, 2024.
Figure 5. Growing season cumulative rainfall (mm) observed across the Canadian prairies for the period of April 1 – June 30, 2024.

Soil moisture conditions (top 5 cm) continue to be driest for western regions of Saskatchewan and eastern regions of Alberta (Figure 6) and is similar to the 30 day cumulative rainfall map (Figure 4). Soil moisture values were greatest for Manitoba and the Parkland region of Saskatchewan. Lowest values occurred across southern and central regions of Alberta as well as southwestern Alberta.

Figure 6. 7 day average saturated soil moisture (% soil moisture for the surface layer, <5 cm depth) for the period of June 24-30, 2024.

Growing degree day (GDD) maps for the Canadian prairies for Base 5 ºC and Base 10 ºC (April 1-July 1, 2024) can be viewed by clicking the hyperlinks. Over the past 7 days (to July 3, 2024), the lowest temperatures recorded across the Canadian prairies ranged from -22 to 7 °C while the highest temperatures observed ranged from 4 to 28 °C. In terms of precipitation across the Canadian prairies, review the growing season accumulated precipitation (April 1-July 3, 2024), the growing season percent of average precipitation (April 1-July 3, 2024), and the past 7 days (as of July 3, 2024). Access these maps and more using the AAFC Maps of Historic Agroclimate Conditions interface.

Growers can bookmark the AAFC Maps of Current Agroclimate Conditions for the growing season. Historical weather data can be accessed at the AAFC Drought Watch Historical website, Environment and Climate Change Canada’s Historical Data website, or your provincial weather network. The AAFC Canadian Drought Monitor also provides geospatial maps updated monthly.

Wheat midge

Although the PPMN is unable to model and predict wheat midge development as in previous years, accumulated precipitation levels during May and June provide guidance in terms of in-field scouting. Elliott et al. (2009) reported that wheat midge emergence was delayed or erratic if rainfall did not exceed 20-30 mm during May. Olfert et al. (2016) ran model simulations to demonstrate how rainfall impacts wheat midge population density. The Olfert et al. (2020) model indicated that dry conditions may result in: (a) Delayed adult emergence and oviposition, and (b) Reduced numbers of adults and eggs.

Important the accumulated precipitation levels over past 60 days (May 5 to July 3, 2024) were mapped in Figure 1 and ranged from 60 to >250 mm across the prairies, well beyond the 45 mm threshold that facilitates larvae to exit their cocoons to pupate in the soil then emerge. Areas in Figure 1 receiving substantial rainfall this spring need to plan to scout for wheat midge now as adults typically emerge and seek wheat in early July.

Figure 1. 60 day cumulative rainfall (mm) observed across the Canadian prairies for the period of May 5 -July 3, 2024.

Remember – the rate of development and timing of adult midge emergence varies at the field level and can only be verified through in-field scouting. Midge flight coinciding with the beginning of anthesis is a crucial point when in-field counts of wheat midge on plants are carefully compared to the economic thresholds.

Producers opting to grow cultivars susceptible to wheat midge need to be mindful that any historically elevated density of wheat midge occurring over the past one or even possibly six years across the prairies that also has received substantial rainfall since May of 2024, warrants in-field monitoring now. Review the past wheat midge maps here in relation to your fields THEN compare the historical densities to areas of high precipitation in Figure 1.

In-Field Monitoring: When scouting wheat fields, pay attention to the synchrony between flying midge and anthesis.  In-field monitoring for wheat midge should be carried out in the evening (preferably after 8:30 pm or later) when the female midges are most active. On warm (at least 15 ºC), calm evenings, the midge can be observed in the field, laying their eggs on the wheat heads (Fig. 3). Midge populations can be estimated by counting the number of adults present on 4 or 5 wheat heads. Inspect the field daily in at least 3 or 4 locations during the evening.

Figure 3. Wheat midge (Sitodiplosis mosellana) laying their eggs on a wheat head. Photo: AAFC-Beav-S. Dufton and A. Jorgensen.
Figure 4. Macroglenes penetrans, a parasitoid wasp that attacks wheat midge, measures only ~2 mm long.  Photo: AAFC-Beav-S. Dufton.

REMEMBER that in-field counts of wheat midge per head remain the basis of the economic threshold decision.  Also remember that the parasitoid, Macroglenes penetrans (Fig. 4), is actively searching for wheat midge at the same time.  Preserve this parasitoid whenever possible and remember insecticide control options for wheat midge also kill these beneficial insects who help reduce midge populations.

Economic Thresholds for Wheat Midge:
a) To maintain optimum No. 1 grade: 1 adult midge per 8 to 10 wheat heads during the susceptible stage.
b) To maintain yield only: 1 adult midge per 4 to 5 heads. At this level of infestation, wheat yields will be reduced by approximately 15% if the midge is not controlled.
Inspect the developing kernels for the presence of larvae and larval damage.

Albertans… please refer to this week’s Provincial Insect Pest Report Links to link to count reports of wheat midge for 2024.

Wheat midge was featured as the Insect of the Week in 2023 (for Wk08). Be sure to also review wheat midge and its doppelganger, the lauxanid fly, featured as the Insect of the Week in 2019 (for Wk11) – find descriptions and photos to help with in-field scouting!  Additionally, the differences between midges and parasitoid wasps were featured as the Insect of the Week in 2019 (for Wk12).  Remember – not all flying insects are mosquitoes nor are they pests! Many are important parasitoid wasps that regulate insect pest species in our field crops OR pollinators that perform valuable ecosystem services!

Information related to wheat midge biology and monitoring can be accessed by linking to your provincial fact sheet (Saskatchewan Ministry of Agriculture or Alberta Agriculture & Irrigation).  Alberta Agriculture & Irrigation has a YouTube video describing in-field monitoring for wheat midge.  

Additional information can be accessed by reviewing the Wheat midge pages extracted from the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and Field Guide” (2018) accessible as a free downloadable PDF in either English or French on our new Field Guides page.


Grasshopper Scouting Tips:
Review grasshopper diversity and photos of nymphs, adults, and non-grasshopper species to aid in-field scouting from egg hatch and onwards.
● It is best to scout on warm days when grasshopper nymphs are more active and easier to observe.
● Carefully check roadside ditches and along field edges but also check the edge of the crop and into the actual field.
● Younger or earlier instar nymphs are easier to manage – visit sites every few days to stay on top of local field conditions.
● A sweep-net can ‘detect’ grasshopper nymphs, however, economic thresholds for grasshoppers are based on the number of grasshoppers per square-metre counts.
● Access the PPMN’s Grasshopper Monitoring Protocol as a guide to help implement in-field monitoring.
● Review grasshopper lifecycle, damage and scouting and economic thresholds to support sound management decisions enabling the preservation of beneficial arthropods and mitigation of economic losses.

Important – A preliminary summary of available thresholds for grasshoppers has been kindly shared by Dr. J. Tansey (Saskatchewan Agriculture) in Table 1. When scouting, compare in-field counts to the available threshold value for the appropriate host crop AND for field or ditch situations. Available thresholds (nominal and economic) help support producers while protecting beneficials (i.e., predators, parasitoids, and pathogens) that regulate natural populations of grasshoppers.

Biological and monitoring information (including tips for scouting and economic thresholds) related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan Ministry of AgricultureAlberta Agriculture and Irrigation, the BC Ministry of Agriculture, and the Prairie Pest Monitoring Network.  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” (2018) accessible as a free downloadable PDF in either English or French on our Field Guides page. Review the historical grasshopper maps based on late-summer in-field counts of adults performed across the Canadian prairies.

Diamondback moth

Please refer to this week’s Provincial Insect Pest Report Links to find the most up-to-date information summarizing weekly cumulative counts compiled by provincial pheromone trapping networks across the Canadian prairies in 2024.

Scouting and pest management for diamondback moth depends on in-field counts of larvae per metre2! This means plants need to be pulled and tapped off to assess the number of larvae! Use Figure 1 below to help identify the different stages of the diamondback moth.

Figure 1. The life stages of the diamondback moth (Plutella xylostella), which can have multiple generations per year. Photos: AAFC-Saskatoon-J. Williams.

The economic threshold for immature and flowering canola is 100-150 larvae per metre2. Biological and monitoring information for DBM (including tips for scouting and economic thresholds) is posted by Manitoba AgricultureSaskatchewan Ministry of Agriculture, Alberta Agriculture and Irrigation, and the Prairie Pest Monitoring Network.  Also, refer to the diamondback moth 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 Field Guides page.

Cabbage seedpod weevil

There is one generation of cabbage seedpod weevil (CSPW; Ceutorhynchus obstrictus) per year. The overwintered adult is an ash-grey weevil measuring 3-4mm long (e.g., lower left photo).  Mating and oviposition are quickly followed by eggs hatching within developing canola pods (e.g., lower right photo). The highly concealed larvae feed within the pod, consuming the developing seeds.

Damage: Adult feeding damage to buds is more evident in dry years when canola is unable to compensate for bud loss.  Adults mate following a pollen meal then the female will deposit a single egg through the wall of a developing pod or adjacent to a developing seed within the pod (refer to lower right photo).  Eggs are oval and an opaque white, each measuring ~1mm long.  Typically a single egg is laid per pod although, when CSPW densities are high, two or more eggs may be laid per pod.

There are four larval instar stages of the CSPW and each stage is white and grub-like in appearance ranging up to 5-6mm in length (refer to lower left photo).  The first instar larva feeds on the cuticle on the outside of the pod while the second instar larva bores into the pod, feeding on the developing seeds.  A single larva consumes about 5 canola seeds.  The mature larva chews a small, circular exit hole from which it drops to the soil surface and pupation takes place in the soil within an earthen cell.  Approximately 10 days later, the new adult emerges to feed on maturing canola pods.  Later in the season, these new adults migrate to overwintering sites beyond the field.


  • Begin sampling when the crop first enters the bud stage and continue through the flowering. 
  • Sweep-net samples should be taken at ten locations within the field with ten 180° sweeps per location.  
  • Count the number of weevils at each location. Samples should be taken in the field perimeter as well as throughout the field.  
  • Adults will invade fields from the margins and if infestations are high in the borders, application of an insecticide to the field margins may be effective in reducing the population to levels below which economic injury will occur.  
  • An insecticide application is recommended when three to four weevils per sweep are collected and has been shown to be the most effective when canola is in the 10 to 20% bloom stage (2-4 days after flowering starts). 
  • Consider making insecticide applications late in the day to reduce the impact on pollinators.  Whenever possible, provide advanced warning of intended insecticide applications to commercial beekeepers operating in the vicinity to help protect foraging pollinators.  
  • High numbers of adults in the fall may indicate the potential for economic infestations the following spring.

Albertan growers can report and check the live map for CSPW posted by Alberta Agriculture and Irrigation (screenshot provided below for reference; retrieved 2024Jul04).

Please find additional detailed information for CSPW in fact sheets posted by Alberta Agriculture and IrrigationSaskatchewan Ministry of Agriculture, or the Prairie Pest Monitoring Network.  Also refer to the cabbage seedpod weevil 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. The Canola Council of Canada’s “Canola Encyclopedia” also summarizes CSPW.

Alfalfa weevil

The alfalfa weevil, Hypera postica, overwinters as an adult that typically flies to alfalfa fields in April and May. Adult females start to lay eggs in May. Adults consume alfalfa foliage, but typically do not cause economic levels of damage. However, larval feeding peaks in June and, if high densities are present, can cause yield losses. Thus, field scouting to assess larval stages and densities should begin in May through to June. Review the alfalfa weevil life cycle and the damage it causes.

Reminder – The larval stage of this weevil feeds on alfalfa leaves in a manner that characterizes the pest as a “skeletonizer” (Fig. 1).  The green larva featuring a dorsal, white line down the length of its body has a dark brown head capsule and will grow to 9 mm long.  Alfalfa growers are encouraged to check the Alfalfa Weevil Monitoring Protocol prepared by Dr. Julie Soroka (AAFC-Saskatoon).

Figure 1. Alfalfa weevil injury to alfalfa; (a, b) leaf notching and skeletonizing and (c) injury to stem tips. Photos: AAFC-Soroka.

Economic Thresholds and Control:
Economic thresholds for alfalfa weevil vary with the alfalfa crop type (whether hay or seed) the advising body, and the measurable unit. In hay fields, forage losses can be economic if one or more of the following symptoms are noted:
• if 25-50 % of the leaves on the upper one-third of the stem show damage, or
• if 50-70% of the terminals are injured, or
• if 1 to 3 third or fourth instar larvae occur per stem (with shorter stems having lower economic thresholds and 3 or more larvae requiring treatment no matter what the alfalfa height), or
• 20-30 larvae per sweep occur when 12 % leaf loss is acceptable.

Early cutting of the first growth of alfalfa or insecticide treatment will reduce alfalfa weevil populations. If the hay crop value is high and weevil injury is seen or 2 or more larvae per stem reappear in regrowth after cutting, insecticide may be necessary if a second cut is anticipated. In alfalfa seed fields, economic thresholds are 20-25 third to fourth instar larvae per sweep or 35-50 % of the foliage tips showing damage. Thresholds increase with the height of the alfalfa, and decrease in drought conditions. Several small wasps parasitize alfalfa weevil larvae and adults, and in the past these natural control agents kept the weevil in check in most years. One of these wasps, Bathyplectes curculionis (Thomson), (Fig. 3a-c), parasitizes alfalfa weevil in Alberta and Saskatchewan, and is now found in Manitoba.

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.

Bertha armyworm

Weekly Pheromone-baited Trapping Results – Early season detection of bertha armyworm is improved through the use of pheromone-baited unitraps traps deployed in fields across the Canadian prairies. Please refer to this week’s Provincial Insect Pest Report Links to find the most up-to-date information summarizing weekly cumulative counts compiled by provincial pheromone trapping networks across the Canadian prairies in 2024.

Remember: in-field scouting is required to apply the economic threshold to manage both this pest and its natural enemies. Use the images below (Fig. 1) to help identify moths from the by-catch that will be retained in the green phermone-baited unitraps.

Figure 1. Stages of bertha armyworm from egg (A), larva (B), pupa (C), to adult (D). Photos: J. Williams (Agriculture and Agri-Food Canada).

Refer to the PPMN Bertha armyworm monitoring protocol for help when performing in-field scouting or review the 2024 Insect of the Week featuring bertha armyworm. Also scan over the 2019 Insect of the Week featuring bertha armyworm and its doppelganger, the clover cutworm! 

Biological and monitoring information related to bertha armyworm in field crops is posted by the provinces of ManitobaSaskatchewanAlberta 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.

Cereal leaf beetle

The cereal leaf beetle (Chrysomelidae: Oulema melanopus) has a broad host range. Wheat is the preferred host, but adults and larvae also feed on leaf tissue of oats, barley, corn, rye, triticale, reed canarygrass, ryegrass, fescue, wild oats, millet and other grasses. Yield quality and quantity is decreased, if the flag leaf is stripped. Fortunately, the parasitoid wasp, Tetrastichus julis Walker (Hymenoptera: Eulophidae), is an important natural enemy of cereal leaf beetle larvae. Learn more about this beneficial insect species featured in Week 9 of 2023’s Insect of the Week!

Cereal Leaf Beetle Lifecycle and Damage:

Larva: The larvae hatch in about 5 days and feed for about 3 weeks, passing through 4 growth stages (instars). The head and legs are brownish-black; the body is yellowish. Larvae are usually covered with a secretion of mucus and fecal material, giving them a shiny black, wet appearance (Fig. 1).  When the larva completes its growth, it drops to the ground and pupates in the soil. 

Figure 1.  Larval stage of Oulema melanopus with characteristic feeding damage visible on leaf (Photo: M. Dolinski).

Pupa: Pupal colour varies from a bright yellow when it is first formed, to the colour of the adult just before emergence. The pupal stage lasts 2 – 3 weeks. Adult beetles emerge and feed for a couple of weeks before seeking overwintering sites. There is one generation per year.

Adult: Adult cereal leaf beetles (CLB) have shiny bluish-black wing covers (Fig. 2). The thorax and legs are light orange-brown. Females (4.9 to 5.5 mm) are slightly larger than males (4.4 to 5 mm). Adult beetles overwinter in and along the margins of grain fields in protected places such as in straw stubble, under crop and leaf litter, and in the crevices of tree bark. They favour sites adjacent to shelterbelts, deciduous and conifer forests. They emerge in the spring once temperatures reach 10-15 ºC and the adults are active for about 6 weeks. They usually begin feeding on grasses, then move into winter cereals and later into spring cereals.  

Figure 2. Adult Oulema melanopus measure 4.4-5.5 mm long (Photo: M. Dolinski).

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.

West nile virus

While the PPMN no longer predicts the development of Culex tarsalis, the vector for West Nile Virus (WNV), areas of the Canadian prairies in 2024 have received high levels of precipitation. This is noteworthy because the larvae of C. tarsalis can develop in, “agricultural tailwater, alkaline lake beds, fresh and saline wetlands, secondary treated sewage effluent and oil field run-off” (Centre for Vector Biology URL retrieved 2024Jul04).

Historically, by mid-July, C. tarsalis adults begin to fly in southern parts of the Canadian prairies. Field scouts and outdoor enthusiasts should wear DEET to protect against C. tarsalis and WNV.

The Public Health Agency of Canada posts information related to West Nile Virus in Canada. Link here to view the latest case numbers and seasonal updates. Bird surveillance continues to be an important way to detect and monitor West Nile Virus. The Canadian Wildlife Health Cooperative (CWHC) works with governmental agencies (i.e., provincial laboratories and the National Microbiology Laboratory) and other organizations to report the occurrence of WNV. Access information on surveillance posted by the provinces of Manitoba, Saskatchewan, or Alberta.

Monarch migration

Track the migration of the Monarch butterflies as they move north by checking the 2024 Monarch Migration Map!  A screenshot of Journey North’s “first sightings of adults” map was featured Wk07. This week, the updated map of “first sightings of LARVAE” has been placed below (retrieved 04Jul2024) but follow the hyperlink to check the interactive map.  Larvae have been spotted in Manitoba so far!

Access this Post to help you differentiate between Monarchs and Painted Lady Butterflies!

Visit the Journey North website to learn more about migration events in North America and visit their monarch butterfly website for more information related to this amazing insect. 

Provincial insect pest report links

Prairie-wide provincial entomologists provide insect pest updates throughout the growing season. Follow the hyperlinks to readily access their information as the growing season progresses:

MANITOBA’S Crop Pest Updates for 2024 are available. Access the online July 4, 2024 report (or PDF copy). Bookmark the insect pest homepage to access fact sheets and more! Highlights pulled from the latest report include:
Flea beetles – Dr. J. Gavloski reported, “some spraying for flea beetles in late-seeded fields over the past week”.
Alfalfa weevil – Was “at high levels in alfalfa and other forage legumes in some fields; there have been reports of high levels now from the Interlake, Eastern, Northwest and Southwest regions”.
Bertha armyworm pheromone trap monitoring – Reports moths in “58 of 79 traps” although “counts have been low so far”. Access the PDF copy of the July 4 report.
Diamondback moth pheromone trap monitoring – Reports that trapping is complete for 2024 with moths present “in 75 out of 92 traps” and that, “trap counts were generally been low in the Northwest and Southwest regions with a few traps in the Northwest exceeding 25 moths” and “some moderate to high counts in the Eastern, Central, and Interlake regions”. The highest cumulative trap count was 233 from a trap near Riverton in the Interlake region.” Access the PDF copy of the July 4 report.
True armyworm in MB – “Armyworms have been caught in 34 traps so far. Eighteen traps have intercepted >25 moths; three in the Central region, five in the Eastern region, and ten in the Interlake region. The highest cumulative trap count so far is 434 from a trap near Riverton in the Interlake region.” Scouting for larvae in cereals and forage grasses is still recommended in areas of the Central, Eastern, and Interlake regions. “Armyworm larvae have been reported in the Central and Interlake regions, with some control applied in the Interlake region”. Access the PDF copy of the July 3 report.
• Features a description of the alfalfa weevil with a link to the fact sheet.
• Advises of an emergency registration of Carbine in confection sunflowers in Manitoba from July 21, 2024 to July 20, 2025 to control lygus bugs.

SASKATCHEWAN’S Crop Production News is back for the 2024 growing season! Access the online Issue #3 report. Bookmark their insect pest homepage to access important information! A brief summary of the week was provided by Dr. J. Tansey (as of June 27):
Insect pests to watch – “Flea beetles were reported as minor to moderate issue throughout the province with spraying reported in NW and some serious issues reported from a small number of sites in SW”. There was “some minor root maggot damage reported in EC and NE” and “limited moderate wireworm problems in the SW and EC”. “Cutworm pressures were generally low but moderate pressures were reported in the SE”. More recently this week, “barley thrips activity” was reported.
Grasshopper nymphs – “Grasshopper issues were sporadic but moderate pressures were reported in central regions and limited severe pressure in SW.”
Diamondback moth Cumulative count data from pheromone traps across the province is complete for 2024 and can be reviewed online. A total of 24 sites intercepted a cumulative total of ≥25 moths so in-field monitoring for larvae should be prioritized in those areas.
• Also access the Crops Blog Posts that released a grasshopper activity update, announced registration for the Crop Diagnostic School 2024 but also posts help for scouting fields for wireworms (May 2024), grasshopper identification: pest or not (Apr 2024), a summary of wheat midge populations and management (Mar 2024), and a description of pea leaf weevil populations (Feb 2024).

ALBERTA’S Insect 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. Remember, AAF’s Agri-News occasionally includes insect-related information, e.g., soil moisture, wheat midge and other insect pests (June 24, 2024), scout for grasshoppers and other insect pests (June 17, 2024); how to manage stem feeding from flea beetles, keep canola bins malathion-free, scout for grasshoppers and other pests (June 10, 2024); scout for insect pests (June 3, 2024); scout for grasshoppers (May 27, 2024); flea beetle control (May 6, 2024); cereal insect pests, latest on insects in canola, and post-emergence wireworm scouting (May 13, 2024).
Wheat midge monitoring update for AB – Cumulative counts arising from weekly data are available so refer to the Live Map. So far, cumulative trap counts from 6 trap locations are all reporting both “medium” and “high” risk as of July 4, 2024).
Cabbage seedpod weevil monitoring update for AB – Sweep-net count data can be reported here then populates the Live Map. So far, a total of 8 sites in southern Alberta are reporting; there are 6 “low risk” plus 2 “high risk” reports as of July 4, 2024).
Bertha armyworm pheromone trap monitoring update for AB – Cumulative counts arising from weekly data are available so refer to the Live Map. So far, cumulative trap counts from 242 trap locations are all reporting “low risk” category as of July 4, 2024).
Diamondback moth pheromone trap monitoring update for AB – Cumulative counts arising from weekly data are available so refer to the Live Map. Cumulative trap counts have been recorded from 32 reporting sites and 28 remain in the “no risk” category as of July 4, 2024). Four trap locations have caught > 25 adult diamondback moths; sites fall within the County of Grande Prairie (as of June 8, 2024), County of Warner (as of June 15, 2024), Vulcan County (as of June 15, 2024), and County of Barrhead (as of June 15, 2024).
Cutworm live monitoring map for AB – Cumulative counts arising from weekly data are available so refer to the Live Map. So far, 10 surveyed sites have reported from across the province, nine falling within southern Alberta and one report from the County of Grande Prairie.

Crop report links

Access the latest provincial crop reports produced by:
Manitoba Agriculture (subscribe to receive OR access a PDF copy of the July 2, 2024 report).
Saskatchewan Agriculture (or access a PDF copy of the June 25-July 1, 2024 report).
Alberta Agriculture and Irrigation (or access a PDF copy of the June 25, 2024 report).

The following crop reports are also available:
• The United States Department of Agriculture (USDA) produces a Crop Progress Report (access a PDF copy of the July 1, 2024 edition).
• The USDA’s Weekly Weather and Crop Bulletin (access a PDF copy of the July 2, 2024 edition).

Previous posts

As the growing season progresses, the Weekly Update topics move on and off the priority list for in-field scouting. It remains useful to keep the list at hand to support season-long monitoring. Click to review these earlier 2024 Posts (organized alphabetically):
2023 Risk maps
Cicada – Rare co-emergence of broods (Wk07)
Crop production guide links (Wk 03)
Cutworms (Wk 05)
Field heroes (Wk 05)
Flea beetles (Wk 04)
Invasive insects (Wk 06)
Pea leaf weevil (Wk 05)
Prairie Crop Disease Monitoring Network (Wk 08)
Prairie Weed Monitoring Network (Wk 06)
Scouting charts – canola and flax (Wk 03 of 2022)
Tick tips (Wk 04)
Wind trajectory summaries unavailable (Wk 01)