It's the number of cut. Usually off of a field you'll get a first cut and a second cut, and in some places you can get 3 cuts of hay. #1 cut is super coarse, they usually only feed it to cows or use it on lawns and stuff. #2 is softer, and that's most of the timothy/orchard that's out there for bunnies and rabbits. #3 is the softest, and the hardest to get, but it's good, good stuff and most of the little critters seem to prefer it.
We are as gods to the beasts of the fields. We order the time o' their birth and the time o' their death. Between times, we ha' a duty. - Terry Pratchett.
"Men have forgotten this truth", said the fox, "But you must not forget it. You become responsible, forever, for what you have tamed. - Antoine de Saint-Exupéry