It's cold at the farm as well as everywhere else. As I sit and write this it's 2 above zero and calm. Good thing the wind isn't blowing or it would be a heck of a lot colder than it is now. There's plenty of cold weather forecasted so I guess we'll have plenty of snow and ice this year and perhaps, just perhaps, have a normal spring.
Last week I wrote about Indian meal moths; a pest of stored grain. Another pest of stored grains is the grain mite – today's subject. Last fall while feeding my chickens one day I noticed a patch of tiny insects on the side of the garbage can (where I store my feed). Always alert to insects in the henhouse I investigated the clusters to make sure they weren't bird lice. Upon close inspection one day as I was loading grain into the bins the patches were indeed masses of tiny insects about the size of chicken lice. There were thousands of them clustered near where the handles are attached to the cans. They crawl like bird lice but don't eat anything but seeds and grains so are harmless to humans. Evidently they don't bother the hens as they got dumped into the feeders whilst I was feeding the hens.
Grain mites infect all kinds of food and feed products, cereals, dried vegetable materials, cheese, corn and dried fruits. They thrive in humid conditions; high humidity and warm conditions. At 90% humidity and 75 degrees, their entire life cycle may only take nine to eleven days to complete whereas under lower humidity and cooler temps the same process may require up to a month.
Females lay up to 800 eggs in their lifetime at the rate of twenty to thirty per day. She may lay them in clusters or singly on the food surface. As the young mites grow they may change into a stage called hypopus. At this time their body walls may harden and they develop suckers on their legs with which they use for transporting themselves by attaching to other insects and mice to hitch a ride. This is how they migrate to other grains in storage. At this stage they are more resistant to insecticides than at other stages of their lives. Once they find a new home they simply drop off, lose their hardened shells and resume growing.
While I was researching this article I didn't see anything to point to their being a hazard to livestock but I was anxious to get rid of them anyways. They are quite resilient to pesticides in certain stages of their life cycle. Freezing (like for Indian meal moths) works marginally well, microwaving works well for small lots but I do not see most people microwaving their grain stocks. There are some insecticides labeled for their control but I'd rather not use them in the henhouse; insecticides only knock down their population but does nothing for longer term control.
The official answer to everyone's question is: "The best way to avoid an infestation is not to get them in the first place". You know, I've always hated an answer like that. Too condescending; if I didn't have them I probably wouldn't be reading and writing about them. I want a solution that is least toxic, easy and achieves the goal of eradication.
I found that simple steps in good sanitation eliminated the population. Eliminating grain dusts, using my older grain first, not buying more than I needed for a couple of weeks at a time, and giving the grain storages a good and thorough cleaning out between batches of grain, I haven't seen the mites since. Of course its winter and I wouldn't see them now anyways. I'll keep an eye open for them next season but I don't expect to see them again.
Until next week, stay warm.