I would betcha they just aren't ferociously hungry and are waiting for the old familiar stuff to reappear
Timothy is perfectly good horse hay; hay is certainly allowed (to some extent supposed) to be green; and *alfalfa* (not timothy) is the hay that usually has blister beetles and horses can't detect them before they eat them anyhow.
I'd just leave it there for a day or two or three (depending on how much you worry about your horses -- a chronic colicker or a nursing mare or something like that I wouldn't leave nearly so long) and see if they start in on it. I bet they will
As for how much to feed, for now you can just play it by eye depending on how much they're eating - no sense putting out a bunch that will just get wasted. But in general, if it's their sole source of roughage and sole-or-major source of calories, figure an average 1000-lb horse will need something like 15-20 lbs of hay per day. Depends on the hay, depends on the horse, depends how much is being wasted. For yours, at least two (possibly all 4) of which are probably easy keepers, I'd guesstimate 1 bale per day as a reasonable starting point.
Good luck,
Pat

Timothy is perfectly good horse hay; hay is certainly allowed (to some extent supposed) to be green; and *alfalfa* (not timothy) is the hay that usually has blister beetles and horses can't detect them before they eat them anyhow.
I'd just leave it there for a day or two or three (depending on how much you worry about your horses -- a chronic colicker or a nursing mare or something like that I wouldn't leave nearly so long) and see if they start in on it. I bet they will

As for how much to feed, for now you can just play it by eye depending on how much they're eating - no sense putting out a bunch that will just get wasted. But in general, if it's their sole source of roughage and sole-or-major source of calories, figure an average 1000-lb horse will need something like 15-20 lbs of hay per day. Depends on the hay, depends on the horse, depends how much is being wasted. For yours, at least two (possibly all 4) of which are probably easy keepers, I'd guesstimate 1 bale per day as a reasonable starting point.
Good luck,
Pat