It goes without saying that you want to feed good hay, with little to no dust. That’s a fact. But it’s rare to find 100% totally dust free hay, simply because of the process of how the hay is grown and baled. It’s vegetation that grows on the ground! Dry dirt is dust. It gets dustier if it has rained a few days before bailing out. It gets moldy if it rains just before and it is too wet or if it rained after it was cut and left in the field and then baled. I can smell mold and mildew from a mile away, I’m allergic to that. But even if it wasn’t, mold and mildew show up in other ways, no pun intended.
If you pick up one or two flakes of hay and it’s heavier than the others, you probably have mold. Sniff, (from an arm’s length if you’re like me). If it smells musty, open it up and take a look. Mold is obvious and so is mildew. If it’s a bit iffy, don’t feed it. Better safe than sorry. If the hay has a significant amount of dust and doesn’t smell musty or moldy, you may choose to soak, hose it down, or return it. If it’s just a small amount of dust, shake it off and moisten it. In a perfect world, all the hay would be free of dust. This is not a perfect world. If it were, all the hay would be cut a week after a good rain; it would sit row after row curing in a sunny field for days before being baled. And it would smell like fresh green grass.