Stressed Out Soybeans Invite Spider Mites

The soybean crop in southern Illinois has been under some stress and that has allowed spider mites to make an unexpected appearance.

Farmers may notice yellowish to brown leaf tissue on 10-25 percent of the plant. It could be stippled, meaning the soybean leaf will have light and dark spots, and it may include some webbing the spider mites leave behind.

University of Illinois-Extension’s entomologist, Nick Seiter says that lack of rain is a contributing factor. “Spider mites perform well on stressed out plants. Usually, that is drought stress. When you get into this situation early, it could be a combination of stresses; drought, the cold temperatures early that stunted plants, getting dinged by herbicides, all of these things can contribute but drought tends to be the big driver,” according to Seiter.