ENID, Okla. — Barn hay storage
A number of studies have been done comparing various storage methods for large round bales of hay. The results varied greatly depending on the weather during the storage period.
The kind and quality of hay, tightness and size of bales, and the length of time stored also affect losses. In each test, though, it was clear a significant amount of dry matter was lost in field-stored hay, and the quality (digestibility) of the remaining hay was lowered.
Size of the bale affects losses because typically the outer 4 to 6 inches of the bale is lost, and that outer layer represents a higher portion of a small bale than a large bale. The outer 6 inches of a 4-foot diameter bale represents about 44 percent of the bale, while the same outer 6 inches of a 6-foot diameter bale represents 31 percent of the bale.
If we start with a 1,000-pound bale at 85 percent dry matter and 54 percent digestibility, we have (1,000 multiplied by 85 percent) equals 850 pounds of dry matter and (850 multiplied by 54 percent) equals 459 pounds of digestible hay.
If that bale is stored on the ground, losing 30 percent of its dry matter and lowering the digestibility to 45 percent, we now have (850 multiplied by 70 percent) equals 595 pounds of dry matter and (595 multiplied by 45 percent) equals 268 pounds of digestible hay. This represents a loss of 42 percent of digestible hay. The actual savings on hay storage depends on the value of the hay, the length of storage and the weather during the storage period.
Should you store all of your hay in a barn? Not necessarily. Hay harvested late in the season and fed early in the winter would have much lower loss than hay stored over a longer period. One strategy would be to store early hay in a barn, mid-summer hay under tarps, and late hay in the open (if barns and tarps are all full).