KEY PRACTICE: Follow insect thresholds to manage input costs against potential yield response. Conserve and protect natural enemies and beneficial insects by using economic thresholds to determine the need and timing for insecticidal controls.

KEY RESEARCH: Bracken, G.K. and Bucher, G.E. “An Estimate of the Relation Between Density of Bertha Armyworm and Yield Loss on Rapeseed, Based on Artificial Infestations.” Journal of Economic Entomology (1977).

Carcamo, Hector, Agriculture and Agri-Food Canada (AAFC). “Refine and Validate Economic Threshold for Lygus Bugs in Canola Production in Alberta.” project.

Wise, I.L. and Lamb, R.J. “Economic Threshold for Plant Bugs, Lygus spp. (Heteroptera: Miridae), in Canola.” The Canadian Entomologist (1998).

Prevention of significant insect infestation is an essential long-term component of integrated pest management. Economic thresholds determine the need and timing for insecticidal controls based on potential yield reductions from insect damage while helping to conserve and protect natural enemies and beneficial insects.

If insect counts are at the threshold, yield benefit from an insecticide spray will be enough to cover the product and application cost of the spray on a breakeven basis. When insect numbers rise above the threshold, there will be a return on investment.

You can also read the 2014 Science Issue of Canola Digest as a flipbook

Visit the Canola Research Hub website to search the database of grower funded research

Tags: bertha armyworm, insects, lygus, research