Hay is dried grass or legumes cut, stored, and used for animal feed, particularly for grazing animals like cattle, horses, goats and sheep.
It is fed when or where there is not enough pasture or rangeland on which to graze an animal, or when lush pasture by itself is too rich for easy digestion by the animal. Pigs may be fed hay, but they do not digest plant fiber very efficiently.
Commonly used plants for hay include mixtures of grasses such as rye grass (Italian rye grass, Lolium multiflorum) orchard grass and other native species, depending on region.
Many types of hay may also include legumes such as alfalfa (lucerne) and clovers (Trifolium). Pasture flowers are also frequently a part of the mix, though other than legumes, which ideally are cut pre-bloom, flowers are not necessarily desired.
Oat, barley and wheat are occasionally seen in hay products,though more often only the stems are dried and baled after the grain is harvested,making a product called straw that is used for animal bedding and generally is considered poor animal fodder.
It is the leaf and seed material in the hay that determines its quality.Farmers try to harvest hay at the point when the seed heads are not quite ripe and the leaf is at its maximum when the grass is mowed in the field.
The cut material is allowed to dry so that the bulk of the moisture is removed but the leafy material is still robust enough to be picked up from the ground by machinery and processed into storage in bales, stacks or pits.
Hay is very sensitive to weather conditions, particularly when it is harvested.In drought conditions, both seed and leaf production are stunted, making hay that has a high ratio of dry coarse stems that have very low nutritional values. If the weather is too wet, the cut hay may spoil in the field before it can be baled. Or the hay may develop rot and mold after being baled, creating the potential for toxins to form in the feed, which could make the animals sick. It also has to be stored in a manner to prevent it from getting wet. Mold and spoilage reduce nutritional value and may cause illness in animals.
The successful harvest of maximum yields of high-quality hay is entirely dependent on the co-incident occurrence of optimum crop, field, and weather conditions.When this occurs, there may be a period of intense activity on the hay farm while harvest proceeds until weather conditions become unfavourable.
Hay mowing with horses;1890.
Up to the end of the19th century, grass and clover were not often grown together because crops were rotated. However, in the growing season, usually spring, farms produced more fodder than the animals could consume. Some fields were "shut up" for hay. Just as the leafy material was at a maximum in the pasture, immediately before the grasses flowered if judged correctly, the pasture was cut. Much of it was still being cut by scythe by teams of men. Later, this would be done by horse-mower and, from the 1930s onward, by tractor. By the 1930s, good pasture management meant that highly productive pastures were a mix of grasses and legumes, so compromises were made when it was time to mow. Later still, some farmers grew crops, like straight alfalfa (lucerne), for special-purpose hay such as that fed to dairy cattle.
Hay mowing in fall.