When you have a crop of hay, which provides the greatest amount of protection, a barn or a tarp? If you guessed the former, think about the features of hay tarps for a moment. Treated to be UV resistant and waterproof, poly tarps keep out mold and moisture, saving more of your crop during the months in storage. Moisture buildup can be a problem in wood and metal structures, such as barns, and your hay, while in storage, may end up decimated by rot or mold. Hay tarps
are made from heavy duty polyethylene and wrap around multiple bales to keep out UV rays and moisture. Tarping hay stacks can reduce moisture buildup. When wrapped tightly, hay tarps can act as a barrier against condensation and moisture. Generally, the more air circulation that flows around your hay bales, the more opportunity there is for rot, mildew and fungal growth caused by water seeping into the hay. With a close fitting tarp barrier, sources of moisture can't creep in unnoticed.
Hay tarps are treated to be waterproof, UV resistant, mildew resistant, and rot proof. When secured in place, the material blocks out water and UV rays and, as air is not locked in, moisture is allowed to circulate. A large or custom size may be needed for hay tarps, but measure the amount of material you will need first. The tarp wraps around three to 10 bales in a triangular formation, and the diameter of each bale and the amount you stack determine the tarp size needed. Typical stacks include two bales on the bottom and one on the top, making a 2-1 formation. Other popular options include 2-2-1, 3-2-1, and 4-3-2-1. The bales themselves may have a diameter of 48 to 72 inches. Based upon these factors, you can calculate the appropriate size for a hay tarp. As an example, a 3-2-1 formation of 48-inch bales will need a 25 by 45 foot tarp, while a 4-3-2-1 formation of 72-inch bales will need a 40 by 60 foot tarp. Before you start purchasing large, heavy duty hay tarps, consider the area in which the crop will be kept. Water should not form at the base of any stack, and the hay needs to be kept in an area with appropriate drainage, such as an area with downhill runoff or a proper drain.
Some farmers also find it beneficial to build stacks on the tarps themselves to facilitate easy hauling. If you plan on keeping the stacks outdoors and overnight, bypass placing the tarp underneath the stacks as it may trap unwanted moisture. Instead, wrap the top of the pyramid and secure the lines.