Hay is the general name for a number of dried grasses, flowers and other plants used as off-season food for horses and other animals. Producers usually grow rye grass, oats, or alfalfa in large open fields and wait until the leaves have reached a specific maturity, generally just before their flowering stage. The grasses or plants are then cut with machinery and left to dry on the ground for several days. At this stage, excessive rain may be problematic. Some hay growers will turn the cut grass over for more even drying, a process called tedding.
Once the grass or alfalfa has dried sufficiently, it is gathered up mechanically by a machine called a baler. The rear section of the baler creates rectangular or round bales of hay held together by wire. These bales are left in the field until other laborers can collect them. The traditional rectangular bales are generally stored in special barns called haymows or hay lofts. Modern round bales are usually stacked together in a dry outdoor location and covered with a special plastic tarp for weather protection.
Fresh hay bales continue to dry in place for several months. Because the bales are relatively heavy, compression force may help the bottom of the bales dry even faster. One problem farmers face is the excessive heat generated by the compression of wet grass in the center of the bales. For this reason, most haylofts in barns are airy and open. If the hay is stored in unventilated areas, the excessive heat could actually cause a fire in the loft.
During winter months, or in areas where fresh grass is not readily available, ranchers and farmers typically rely on hay to feed their horses. It is not always as nutritional as regular feed, but it does have enough vitamins and roughage to keep animals healthy for a few months. It might help to think of it as a form of granola or breakfast cereal for horses. Some hay supplies may rot or ferment, rendering them useless for feed but ideal for garden mulch.
Since rye grasses and alfalfa continue to grow throughout the year, hay producers may be able to cut the same field up to three times before the winter freeze. This can prove beneficial for the local farmers and ranchers, since supplies can run dangerously low at times. Some hay sold as emergency or low-cost feed can lead to malnutrition and other problems, so producers who can provide high quality bales in bulk are usually very popular in agricultural circles.