Hay is a feedstock made from a plant of some type (typically alfalfa, but it can also be grass, oats, or other small forages). It goes through a process that can take up to 4 days depending on how wet the crop is when cut, hence, the saying "make hay while the sun shines".
First, it is cut using a mower that cuts the alfalfa plant down to within a couple inches from the ground:
Then, baled into any one of 3 different shapes - small squares (we stopped using these a couple years ago, so I don't have any pictures handy, but picture the small bales of straw - which is the subject of day 3's post - that people have outside their houses as decor right now), large squares, or round bales like this one:
And, fed to animals for food.
We may take as many as 5 cuttings off a single field of alfalfa in any summer, about 3-4 weeks apart as the plant regrows. Alfalfa is a perennial plant, and so we are able to repeat this for 3-4 years. The plant will continue to grow for longer, but imagine like your yard - it eventually gets crabgrass and dandelions growing in it, and so we will cultivate the field and plant another crop (usually corn) for at least a year before returning it to alfalfa.
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