Old hay...hey...
We have been going through bad drought, if you saw some of the hay that was still being sold.... :help: :shock: :bs:
I got some that had to be over 10 yr old just sitting outside in weather to try, it was pretty moldy in some spots, everything still would be eaten after I cut out the moldy parts, which were put to compost, anyways, I told them just they were junk, but someone already came and got the lot on a semi.
They will keep animals alive if things get really desperate, but if they are off and really moldy, yeah, put them back in the ground. Or use to bed, or mulch for garden ... etc etc
If you have a lot & it is not moldy but maybe not much nutrient value by itself, buy some other feed and mix, or just use it as roughage as part of a ration.