More than one insect in a crop?

Cabbage seedpod weevil

Some canola fields have lygus bugs, cabbage seedpod weevils, and diamondback moths. Economic spray thresholds are calculated based on individual species. We don’t have scientific evidence to combine thresholds, but where an “additive” effect of multiple species can make sense is when more than one species are feeding on key yield-producing areas — flowers, buds and pods — at the same time.

For example, if you have lygus bug and cabbage seedpod weevil in the same field and if they are both at 50% or more of their economic spray thresholds, spraying may provide an economic benefit.