June 29, 2010 Managing Windrowed Alfalfa Through Wet Conditions
Recent rains and lingering wet field conditions have hampered alfalfa harvest and may contribute to a condition Nebraska Extension Forage Specialist Bruce Anderson calls “windrow disease.”
This refers to the striped appearance in fields where alfalfa windrows remained so long that regrowth was delayed. Usually it’s due to rained-on hay.
This situation presents special challenges. Weeds often invade, requiring spraying to maintain quality and protect stands. During the next growth period, plants that were not smothered regrow rapidly, while plants underneath the windrow suffer delays. Often part of the field will begin to bloom while windrow-stressed plants are still short and tender. So when do you harvest? When the first plants begin to bloom or do you wait until injured plants are ready?
Two factors can help guide your decision as to when to cut — the health and vigor of your stand and the nutrient needs of your livestock.
Is your alfalfa healthy and regrowing well? If not, wait to cut until stunted plants begin to bloom so you can avoid weakening them even more.
If your alfalfa is in good shape, cut when it will best meet the needs of your animals. Dairy cows need alfalfa that is cut early, so harvest when the first plants begin to bloom. Regrowth of injured plants may be slow after cutting, but this sacrifice is needed for profitable milk production. In contrast, beef cows do not need such rich hay. So let stunted plants recover, and then cut when they are ready to bloom.