Across the corn belt depending on time of year | Back to the soil insecticide misconception!
Soil insecticides only protect the base of the plant providing stand ability for harvest. Soil insecticides applied in a band or in furrow only protects a narrow band around the base of the plant and the brace roots.
Soil insecticides to not kill many rootworms. In fact, according to a 1970s study from either Iowa or Nebraska (haven’t read it in awhile) clearly show a farmer produced more rootworm beetles per acre when a soil insecticide is used to protect the base of the plant. Why? Protecting the base of the plant protects the food source for the rootworms in the middle of the row. In untreated fields, those roots in the middle of the row die because they are detached at the base of the plant and die. Use of soil insecticides increase the number of beetles in your field, increasing the reason you beetle bomb.
Soil insecticides+biocontrol nematodes are still a single source of mortality (the nematodes) because the soil insecticide is only protecting standability and harvest stands |
Biological Control of Rootworm - A link to a recent presentation
