The result of harvesting at a less than ideal time can be different based upon stresses (for examples, spring freeze, competition from weeds, fertility, insect infestations, disease, too rigorous of a cutting schedule, cold winter with no snowfall, winter temperatures fluctuating wildly) the crop has experienced preceding and following the "less than ideal" harvest timing. Variety selection and leaving several unharvested strips in the field to help catch additional snow make a difference, too.
Taking a last scheduled cutting in early September, possibly followed by an “unplanned” cutting in late October, is preferable to a scheduled late September/early October “last” cutting.
“This is a good principle to follow, although the most conservative approach is to not harvest in the fall at all,” Schroeder says.
Weather conditions for producing hay after the alfalfa is dormant makes hay drying difficult, so harvesting the crop as silage or baleage is less risky. If a cool-season grass is growing with the alfalfa, an option might be to graze the residual growth if fencing is available and soil conditions permit grazing. Some strategies include leaving a tall stubble to reduce the chance of ice "hugging" alfalfa crowns, provided the alfalfa is tall enough to still yield forage that can be recovered economically.
Schroeder has this advice for producers trying to decide whether to harvest their alfalfa this fall:
- If this is the last year for the alfalfa, growth is excellent now, its value as a forage exceeds the lost value of nitrogen for the crop that follows and weather is super, then harvest.
- If this is year two or three for the alfalfa, crop vigor is good now and the forecast is for great weather for a week, but the potential loss from the ill-timed alfalfa harvest means that the producer’s financial status will be impaired, keep the mower-conditioner in the shed.
- If you are going to cut the alfalfa, then do so immediately. The extended forecast is for warm weather next week, which would favor hay drying and regrowth.