Pest Profile

Winter grain mite
Penthaleus major

Pest Description

Many times the infested plants do not die, but become stunted and produce little forage or grain. Damage on young plants is more severe than on large, healthy plants.

Winter grain mites have a dark brown to almost black body with conspicuous reddish-orange legs. Their front legs are longer than the others, but not as pronounced as on the brown wheat mite. They also have two tarsal claws on the end of each leg.

Source of information

Kansas Department of Agriculture (, UC Statewide IPM Project (

Pest Diagnostics


Pest photo source

Kansas Department of Agriculture

Plant Diagnostics


Plant diagnostic image(s) source

UC Statewide IPM Project (