True, and an apple is an apple, whether dried or canned.
I was speaking to spontaneous combustion and why sometimes its preferred that the alfalfa is dry and sometimes one might want it wet.
With hay the method of storage is dry, it must be entirely dry. If moisture is present then bacteria grow in the moisture and generate heat which causes the dry portion to combust.
With silage one is "canning" moist food using the power of fermentation. The weight of the pile in the silo expresses juices creating a relatively uniform moisture. Adding water reduces dry pockets which better ensures a uniform environment for the friendly microorganisms and thereby reduces potential for spoilage that would be created by the molds and fungus in the once dry but now damp pockets.
So now you know why the difference. One person already has preserved food and is trying to secure it, the other person has secured food and is trying to preserve it.
Well, thank you very much for the biology lesson. I was more a chemistry type. :-)