Written By: Kemper Sutton and Tim Bryant

Reports of pea leaf weevil activity have come in from New Kent County and the Eastern Shore of Virginia. The pea leaf weevil (Sitona lineatus) is established in Virginia, but it is highly sporadic and rarely considered an economic pest in soybean. However, It has been found causing significant injury to seedling soybean plants this year. Many of the problem fields are soybeans planted into heavy residue from a legume cover crop, like vetch.

Adult weevils feed on seedling foliage, creating characteristic notching along leaf margins. Under heavy infestations, this feeding can lead to economically significant defoliation. Foliar insecticide applications should be considered when defoliation reaches approximately 40% at the seedling stage. Effective control options include pyrethroids such as beta-cyfluthrin, bifenthrin, cyfluthrin, and zeta-cypermethrin.

Larvae can also be a concern, as they develop in the soil and feed on root nodules, potentially reducing nitrogen fixation in host plants. However, currently, there have been no confirmed reports of larval injury in soybean fields in our region.

Fields planted without an insecticide seed treatment may be at greater risk, as seed treatments can provide early protection against both foliar feeding and belowground injury. These fields should be prioritized for scouting.