Losses and Quality Changes During Alfalfa Hay Harvest and Storage

DRY matter loss and change in quality were monitored from standing alfalfa through hay storage. Field curing loss consisted primarily of constituents other than fiber and protein and averaged 3.2% for hay dried without rain damage and 11.2% for hay with rain damage. Protein became less soluble during field curing and a small loss of protein occurred with rain damage. Raking a wide swath into a windrow caused the greatest machine loss; this loss was inversely related to crop yield. The portion of the yield lost was 3.5% for raking, 0.8% for windrow turning, 1.8% for the baler pickup and 1.1% from the baler chamber. Machine losses were similar across all quality constituents so the quality of harvested hay was not affected much by the loss. Storage loss of dry matter averaged 4.2% for dry hay (11 to 20% moisture), 7.9% for 20 to 25% moisture hay and 10.9% for hay of 25 to 34% moisture. This loss was predominantly constituents other than fiber (nonstructural carbohydrate and protein). Carbohydrate loss was proportional to the moisture content of the hay entering storage while protein loss appeared independent of hay moisture.