Winter grain mites

Asked January 14, 2019, 3:19 PM EST

I believe the critters in the attached photos are Winter Grain Mites, penthuleus major. Do you agree? After reading your extension bulletin about these mites I have a couple of questions? In the unmagnified photo they grouped up floating on water. Why do they do this? Also, are these mites common in Jackson County or are they just showing up here? Perhaps one the authors of the bulletin would have a comment. They were Brain Tuck, Mylen Boyle, Amy Dreres and Glen Fisher.

Jackson County Oregon insect issues

2 Responses

it certainly looks like they are winter grain mites. I would contact Gordon Jones at Jackson Extension 541-776-7371, He is going to want to know they are in his area. Take a sample of these critters to him and have him send off to the Plant Clinic for positive ID. I have never seen these mites do this before! Of the four authors, three are retired or moved to another state. You also might want to have Gordon to come out for a farm visit to check out what the mites are up to.

Mylen Bohle
Area Extension Agronomist
Central Oregon
Crook County

Thanks for the response. I’ll contact Gordon Jones.
Dan Kellogg