Winter grain mites have been found in southwest Oklahoma wheat fields, according to Terry Pitts, Oklahoma State University Extension integrated pest management specialist at the OSU Research and Extension Center south of Altus.
These mites are often associated with dry weather such as is now occurring in the affected area. Pitts tells farmers if they see an area in a field of winter wheat with a pale green appearance in they should look closer to determine if the WGM (winter grain mites) are present.
"During colder days, the mites can be found at the base of the plant or even in the cracks of the soil," Pitts said.
"Mites are not true insects," he said. "They are closely related to ticks and spiders. They are dark brown with orange-red legs and an orange or red spot on the upper abdomen.
“Two generations of winter grain mites occur each year. The first begins in the fall as over-summering eggs hatch. The second generation begins sometime in January when the adults lay eggs and reaches peak numbers in March. These mites feed on the leaf sheaths and shoots near the ground. They move up the plant at night and on cloudy days. Leaves of the affected plants take on a slivery gray color and leaf tips may turn brown."
Hosts for the mites, Pitts said, include small grains such as wheat, barley, and oats, all of which are susceptible to mite depredation. Other hosts include grasses, especially bluegrass, bentgrass, ryegrass and fescue. The mite can also infest and damage legumes, vegetables, ornamental flowers, cotton, peanuts and various weeds.
Pitts urges farmers who find mites in their wheat fields to contact their local county Extension office for current control information