Will it pay to play the late-cutting game?

To cut, or not to cut. That is the question Hamlet would ask if only he were a forage producer and not a Shakespeare character. More specifically, the question would be to give alfalfa a longer rest at the end of the season or to cut it before the critical fall period.

In a Midwest Forage Association’s Forage Focus newsletter, Scott Newell with the University of Wisconsin-Madison writes that best management practices for alfalfa persistence include letting plants reach a minimum of 10% bloom at the end of the growing season and avoiding an alfalfa harvest five to six weeks before the first killing frost. The alfalfa outreach specialist explains both strategies are intended to restore root carbohydrates ahead of winter.

Considering this summer’s challenging — and in many cases, delayed — harvest schedule, it may be difficult to adhere to both practices. Giving alfalfa an extended growth period before the last cutting while also harvesting it five to six weeks prior to the first killing frost may not line up on the calendar. With that said, the growing season has been stretching its legs over the years, pushing frost dates farther back from when they have historically fallen.

The Midwest Regional Climate Center’s freeze date tool suggests a more significant trend in longer growing seasons can be found as you move north in Midwestern and Eastern states. Some counties in northern Wisconsin, Minnesota, and South Dakota, for example, show growing seasons that have been drawn out by an average of four to five days in the past decade. Parts of northwest Ohio and central Pennsylvania boast an average six-day extension. The key word here is average.

Postponing a final cutting until alfalfa reaches 10% bloom and avoiding the critical fall period might be feasible if this year’s first frost occurs later than average. On the other hand, making a hard stop on the first of September is a safe card to play, but it is one that could leave farmers wondering if they abandoned good forage in the field when an extended growing season unfolds. Of course, if capturing more forage is the concern, there is the option to take a late fall cutting of alfalfa.

Harvesting alfalfa once colder conditions cease plant growth is a good strategy in theory. Forage that is cut after this point doesn’t necessarily need time to replenish root reserves ahead of winter since it’s not likely that near-dormant plants will use stored carbohydrates to initiate new growth. Late fall cuttings can also provide the highest quality forage of the year, but this may come at the cost of lower yields, delayed green up, and less snow insulation.

Low yields. Fall weather produces forage with finer stems, and therefore, less structural fiber. Fiber digestibility in late alfalfa cuttings also tends to be higher than previous cuttings. Even so, fall growth will not supply a substantial harvest. It could, however, be an expensive one, considering the costs of production.

Delayed green up. In general, the later forage is cut in the fall, the slower it will be to green up in the spring. This is also reflected in spring yields. What is gained in the fall typically equals what is lost in the spring.

Less stubble to hold snow. A physical function of alfalfa regrowth is its ability to catch and hold snow that insulates soil during the winter. Regulating soil temperatures reduces the incidence of plant heaving or alfalfa winterkill from breaking dormancy too early. Harvesting alfalfa in late fall at a regular cut height may not leave enough stubble to fully realize those benefits.

This year is different

Despite the trade-offs, this summer presented challenges to alfalfa harvest that may justify the decision to take a late fall cutting more than previous years. Overall, farmers may simply need to make up for lost quality.

Midwestern producers who endured prolonged harvest delays and rained-on hay due to a saturated early-season forecast are likely sitting on an oversupply of alfalfa that is high in fiber and low in energy. Cooler temperatures and drier conditions may offer a last-ditch effort to secure some high-quality forage, which will otherwise be hard to find in on-farm storage or the local hay market.

Those long stretches of rainy days also led to extensive damage in hayfields as mowers, choppers, trucks, and wagons carved wheel tracks in the wet soil. Wisconsin agronomist Todd Schaumburg predicts heavy traffic in alfalfa this summer may have forfeited one to two years’ worth of yield over the life of a stand.

Instead of anticipating yield drag next spring, Schaumburg suggests getting as much out of damaged stands as possible with a late fall cutting and then rotating alfalfa to the next crop, especially if stands are already three or four years old. At this point, alfalfa typically reaches peak yield per acre before average annual tonnages start to decline. The expected yield drag from wheel damage will only expedite that downward slide.

In this case, producers who usually avoid harvesting alfalfa after the first week of September may have an excuse to capture a higher quality crop without the risk of winter injury or winterkill. Sacrificing spring yields for fall tonnage will also be irrelevant when a late fall cutting is ultimately the last one.

Of course, yield is the driving factor of alfalfa profitability. Lower production in future years could still outweigh the costs of removing a stand ahead of schedule. Whatever route you choose to take — adhering to the critical fall period or taking a late fall cutting — consider the long-term plan for the stand and the consequences of your harvest decision.