The 2024 Insect Survey provides valuable insights into the insect populations across Cardston County, helping local producers and landowners understand potential risks to their crops. Thank you to Rod and all staff involved in the monitoring program, including the important grasshopper survey.
Survey Summary
Wheat Midge
In both dryland and irrigated fields, no wheat midge were detected in 2024. This is largely due to dry conditions during May and June, which interrupted the midge lifecycle. However, wheat midge can remain dormant in the soil for several years, waiting for ideal conditions to emerge.
Risk Level: Low in 2024
Bertha Armyworm (BAW)
None of the monitored sites in Cardston County exceeded the first warning level of 300 moths, with all sites staying well below 100 moths. Regular monitoring is still critical to catch the first signs of population buildup that could lead to outbreaks.
Bertha Armyworm Trap Counts (June 16 - July 27, 2024)
| Location (LLD) | Trap Average |
|---|---|
| SE-11-5-23-W4 | 2.5 |
| SW-25-6-22-W4 | 3 |
| SW-4-2-24-W4 | 7 |
| NE-31-3-24-W4 | 1 |
Wheat Stem Sawfly (WSS)
Sawfly remained a significant concern in 2024 and will likely continue to be an issue in 2025. Dry August weather and early harvests hinder the natural parasitoid, Bracon cephi, which plays a key role in reducing sawfly populations.
Wheat Stem Sawfly Cut Rates (2024)
| Location (LLD) | % of Stems Cut |
|---|---|
| 27-2-21-4 | 18% |
| 10-5-24-4 | 10% |
| N-31-6-23 | 4% |
| NW-16-5-22-4 | 1% |
Pea Leaf Weevil (PLW)
Damage from pea leaf weevil was low overall, with the exception of one localized field. This continues the trend of lower damage levels in southern Alberta.
Pea Leaf Weevil Damage (Average from 5 Locations Per Field)
| Location (LLD) | Avg. Node Stage | Total Notches | Avg. Notches/Plant |
|---|---|---|---|
| SE-17-6-25-W4 | 4.28 | 49 | 0.98 |
| N-27-5-25-W4 | 4.64 | 369 | 7.38 |
| SW-25-3-28-W4 | 4.86 | 4 | 0.08 |
| NE-14-6-22-W4 | 4.26 | 176 | 3.52 |
Cabbage Seedpod Weevil (CSPW)
Weevil numbers were generally low in 2024, though early flowering canola fields remain the highest risk. Ongoing monitoring is needed to detect future spikes.
Cabbage Seedpod Weevil & Other Insects (25-Sweep Samples)
| Location (LLD) | CSPW | Lygus Adults | Lygus Nymphs | Leafhoppers | Flea Beetles | Red Turnip Beetles |
|---|---|---|---|---|---|---|
| E | 25 | 6 | 22 | 4 | 39 | 3 |
| SW | 29 | 2 | 21 | 4 | 33 | 1 |
| SE | 34 | 2 | 25 | 4 | 31 | 0 |
Diamondback Moth (DBM)
Diamondback moth infestations are typically triggered by spring wind currents carrying moths from the U.S. and Mexico. In 2024, trap counts were low.
Diamondback Moth Trap Averages (May 5 - June 16, 2024)
| Location (LLD) | Trap Average |
|---|---|
| SE-12-2-21-W4 | 7 |
| SE-36-11-6-W4 | 2.5 |
Cutworms
While cutworms are not formally monitored, producers are encouraged to report cutworm finds using Alberta’s online reporting tool. One confirmed Army Cutworm case was reported in 2024:
| Location (LLD) | Crop | 2022 Crop | Species | Acres Affected | Spray Required |
|---|---|---|---|---|---|
| SE-25-6-25-W4 | Canola | Wheat | Army Cutworm | 150 | No |
Field Visit Protocol
To protect biosecurity between sites, all field visits followed strict protocols:
✅ No driving into fields
✅ Equipment sanitized between fields with bleach solution
✅ Staff wore disposable boot covers
Important Reminders
- Early Detection: Regular scouting is essential, especially during key periods (early crop growth stages, flowering, heading).
- Weather Impact: Insects like wheat midge and pea leaf weevil are highly affected by spring weather patterns, so conditions each year directly influence risks.
- Risk Mapping: Data collected through these surveys contributes to regional and provincial risk maps, helping producers make informed management decisions.
Questions or Concerns?
For more information about the 2024 Insect Survey or to report a potential pest issue, contact:
Cardston County Agricultural Services
📞 403-653-4977