Second-cut alfalfa is a cherished treasure for many farmers, but is this love warranted? Is it because of their current experience in comparing second-cut alfalfa to first, third, and in some cases fourth or fifth cut? Or is it because of the reputation of second-cut alfalfa hay as a premium crop?
That was then; this is now
Fifty years ago a much higher percentage of alfalfa was harvested as dry baled hay, and was it ever tough to get that first cut dry enough to bale! A perennial grass was often seeded with the alfalfa, and the grass species commonly used in the Northeast thrives under the cool, moist conditions of April and May. (Hence, the name “cool-season” grasses.) And first cut almost always has the highest yield of any cutting.
So a farmer mowing first cut is dropping a heavy crop onto what often is a very moist soil surface. Weather conditions are typically cool and sometimes wet when first-cut alfalfa is mowed in late spring. So between the heavy crop, moist soil and iffy weather it seemed to take forever to get that first cutting dry enough to bale. Much of the reason farmers switched from dry hay to hay crop silage was the difficulty in baling that first crop of alfalfa or alfalfa-grass before it got rained on at least once.
Baling second-cut alfalfa was an entirely different proposition. Because on many farms timothy was the forage grass seeded with alfalfa, and since timothy usually makes little regrowth after first harvest, second cut often was almost pure alfalfa. By then the ground had dried considerably, the days were warmer and there were more hours of sunlight. There also was not nearly as much forage to get dry: Much less grass, and perhaps half the yield of alfalfa compared to first cut. Therefore it was much easier getting second-cut alfalfa dry enough to bale, and because the alfalfa plants were somewhat smaller in stature, they had finer stems.
Contrast that with today’s forage management, where on many progressive dairy farms the baler sits in the far corner of the machinery shed from one year to the next collecting pigeon poop – and that is if it has not already wound up in the weeds behind the barn with other no-longer-used equipment. Many dairy farmers are now “all silage, all the time” and they’ve updated their harvest equipment and increased their silage capacity to accommodate these changes.
We have learned that by the use of wide windrows (at least 70 percent of cutter bar width) farmers can get first-cut alfalfa and alfalfa-grass “from stem to silo” in one day – sometimes in the same day. We have also learned that managing the crop in wide windrows will allow farmers to mow alfalfa before the dew dries, and as long as the crop is harvested for silage it may not be necessary to condition the crop.
A high percentage of alfalfa in the Northeastern U.S. and Eastern Canada is still seeded with a cool-season forage grass, but improved seeding techniques and generally higher soil fertility have resulted in a higher proportion of alfalfa in alfalfa-grass stands.
Why I don’t like second-cut alfalfa
As previously noted, all those fine stems in baled second-cut alfalfa make a very attractive package. But beware: Those stems may be fine but they’re also highly lignified. Alfalfa leaves (actually leaflets) change very little with plant maturity or by cutting. Leaflets have no structural function in the alfalfa plant, thus contain very little fiber. Therefore, unless the plant has a foliar disease the quality of alfalfa leaflets on a full-bloom plant is about the same as that of the leaflets in bud-stage alfalfa.
A college research project at Miner Institute (Chazy, New York) involved sampling individual plants in a field of first-cut alfalfa at the full bloom stage, then second-cut plants at the late bud stage. The plants were then separated into leaves and stems and each component was analyzed. We found that the stem quality of first-cut alfalfa at full bloom was about the same as the stem quality of second cut at the bud stage! As expected, there was no significant difference in leaf quality between first and second cut.
About 50 years ago Cornell University agronomists were recommending that first-cut alfalfa should be harvested at the early bloom stage, with second cut harvested after a six- to seven-week interval. This pretty much guaranteed that second-cut alfalfa would not only be well into bloom, but would have highly lignified, tough stems.
But in the 1960s the average Holstein dairy cow only made about 10,000 pounds of milk per lactation, or half what Holstein cows produce now. We simply cannot achieve today’s milk production levels with yesterday’s forage management. Obviously farmers have to do something with second-cut alfalfa, and that “something” is to manage it very aggressively.
Forget about harvesting according to how many days it’s been since first cut. Farmers need to closely monitor their second-cut alfalfa and when it approaches full bud stage get out there with the mower or mower-conditioner. Often second cut is ready to harvest in less than 30 days, and if there is any crop that I would rather mow a day or two early vs. a day or two late, it’s second-cut alfalfa. Although I know of no research on this topic, if you missed the recommended first-cut stage of conventional alfalfa (not the reduced lignin varieties) by a few days with the result that the crop was in bloom when you mowed it, that is one more reason to be aggressive with second cut. That’s because the alfalfa probably had better-than-normal root carbohydrate levels when mowed the first time. The forage quality of second-cut alfalfa is usually quite different than that of first cut, especially on farms that seed alfalfa-grass.
I’d rather see first cut put in one silo and second and third cuts in a different silo – there may be that much difference in forage quality. That’s another reason why I recommend that farmers have their fresh-chopped hay crops tested for protein and fiber content. These analyses should not be used for balancing rations but will provide a good idea of general forage quality. Knowledge is power!