Lawn Insect – Winter Grain Mite

(Penthaleus major)

The Winter Grain Mite, also known as Penthaleus major, is a relatively large mite that can do seasonal damage to lawns and turfs. These lawn pests are found throughout much of North America and commonly affect Kentucky bluegrass, perennial ryegrass, fescues and creeping bentgrass.

Identifying Winter Grain Mite -

Winter Grain Mite is larger than other turf-infesting mites and is easily visible by the naked eye. It has an olive-black body with bright red-orange legs and mouthparts. There is a pair of white eye spots, and a dorsal anus that are also visible. The eggs are reddish-orange and shiny at first, becoming wrinkled and more straw-colored after a day or two.

The activity and damage caused by this mite is restricted to the winter months and is often mistaken for snow mold or winter kill. Except for the presence of mites, symptoms of injury are the same as those associated with winter desiccation. Symptoms can also resemble that of frost damage in the early spring.

Winter Grain Mites are most active at night and on dark cloudy days. When disturbed, a droplet of liquid appears at the anal opening. This droplet, along with the dorsal anus, is only visible with a 10x lens.

Winter Grain Mite Life Cycle -

Eggs are produced over summer from June to October and the majority of these mites’ activity is during the winter months. Two overlapping generations may occur during the winter with peak populations being found in late December and late February.

Winter Grainmite

Winter Grain Mite Control -

It's best to kill insects, grubs and other pests before they have a chance to cause damage to your lawn. Scotts LawnService recommends our exclusive Scotts® GrubEx® and Ortho® Max™ Pro insect control products, which will kill a wide variety of lawn damaging pests. Ortho® Max™ Pro eliminates destructive, bothersome insects including the Winter Grain Mite, without disturbing the earthworms that are beneficial to your lawn's health.

Scotts LawnService is the trusted industry leader for professional quality lawn care. Our exclusive lawn care products include premium grass seeds and professional-grade fertilizers; our lawn service teams are comprised of highly trained, industry-certified professionals. Contact a representative today for Winter Grain Mite control options available in your area and to learn how you can enjoy a lush, thicker lawn that only Scotts LawnService can deliver.