Seedlings may be lost during periods of water stress and high temperatures. WGM, usually associated with grasses grown for seed actually has a wide host range. It may also cause injury to seedling carrots. Life History Mites overwinter in or on the soil or any protected areas such as crowns of trees and shrubs, fence posts etc. In the spring females migrate to leaves and begin feeding and laying eggs.
Populations peak during late summer and fall.
Infestation and Detection of Mites Field history is important in assessing potential for mite problems. Any fall-seeded crop following a seed crop is at risk. Carrot seed downwind of newly harvested crops or disced ground that had weed cover can receive mites via wind currents. They disperse like spiders on silk threads and travel great distances with the wind. Hot, dry weather and moisture stress enhance mite problems.