Hay is simply the cut down grass and other plants in fields that are gathered together in bundles, either square or round. The plants are cut then allowed to dry in the sun, producing a stiff, dead plant material that is easy to gather for baling machines. Hay bales are a common sight on farms, but they have more than one use and purpose.

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Hay bales are a common sight on farm pastureland.

Storage

On a large piece of land, the amount of hay that can be gathered and baled by the farmer can be quite large. Bales compact the material to clean up the ground and to make it easy for the farmer to store. Without the bales the hay would be difficult to deal with and could only be put into haystacks around the property. Haystacks were common years ago before the invention of the hay baler, but today hay is handled much more efficiently and stored more easily because of this process.

Shoreline Erosion Protection

One of the uses for hay bales is for erosion control. Shoreline erosion can result in damage to fisheries and recreational areas over time, according to the U.S. Army Corps of Engineers website. Water logging hay bales in strategic locations near the shorelines of lakes, rivers or other bodies of water will form a nearly immovable barrier that will help control the force of wind and waves on the shoreline, which will lead to quick erosion. Placing hay bales in an area that will make for smooth, calm water at the shoreline will help the eroding slope to grow vegetation and establish permanently. In a couple of years the bales will naturally erode and will no longer be needed.

Feeding Livestock

Hay is set out in fields for cows, horses or other grazing livestock as a food to help sustain the animals over the winter. The University of Tennessee Extension website recommends that farmers plan on having around 30 pounds of hay available per cow unit for the winter. A cow unit is described as one unit per 1,000 pounds of cattle. Similar measurements work for other animals. Bales act as an easy-to-find food source for animals when there is not enough grazing material available.

Decoration

Hay bales are sometimes used merely for decoration. In the fall and winter you can purchase hay bales to decorate for certain holidays. Halloween displays in a lawn may include hay bales; scarecrows are sometimes used sitting on a hay bale around Halloween or Thanksgiving. Hay bales are also often used to anchor a nativity scene at Christmas.