Sand Colic in the Winter Time?

Winter time is here in Wyoming at the Stamina Plus Research Center. I normally don’t think of sand colic when the ground is frozen and covered in snow. The hay that Stamina Plus purchased last fall has a fair amount of dirt in it. Stamina Plus always purchases the best hay that we can find and it is mold free, dry but does have some dirt in it. When feeding this hay in the individual feeders dirt builds up in the bottom. The dirt is cleaned out daily but my worries are that they may eat some of the dirt. Therefore to prevent this dirt from causing problems we are feeding two scoops of Stamina Plus Fiber daily to all horses. This protocol has worked well and no signs of sand colic have occurred.