Gerald Holmes, California Polytechnic State University at San Luis Obispo, Bugwood.org
Many alfalfa and grass stands have have significant harvest pressures on them. Did you allow at least one cutting of alfalfa to reach mid bloom? Did you apply any fall top-dressing of Potash on these stands? What about your cutting height pressure on the tall cool season grasses like orchardgrass or tall fescue? Some forage producers are noting that even though this was a good growing year for forages some fields seemed to be "a little tired" as the season ran on. Perhaps it was cutting intervals, maybe limiting fertility issues such as lime, or low cutting height.
There is time now to check out your alfalfa stands and predict what conditions the stands will be in next year. Most stands are evaluated in the spring after surviving the winter. Current research shows that fall is the best time to evaluate stands because it allows more time for planning and possible fall herbicide options. Fall evaluation helps to identify potentially less profitable fields and those stands more likely to suffer winter injury. Earlier evaluation permits development of alternative cropping strategies and management for next year. Spring stand evaluation is still suggested to assess the extent of winter injury from weather that is unknown at this time.
Penn State recommends considering stand rotation if the stem count in the 2-foot square averages 45 or less. Wisconsin's recommendation is: more than 55 stems, no need to rotate out. Less than 39 stems definitely consider replacing. When stem count is between 40 and 55, then take a close look at the plant health. If 30% of the crowns and roots show significant rot then rotation is probably necessary. With either system you still need to base final decision on yields normally obtained and your forage alternatives for the coming season.