A number of low-lignin alfalfa varieties are slated to hit the market in 2016. While seed supplies may be limited, and at least one of the versions will be limited to east of the Rockies, farmers should start thinking now how they might manage this higher digestible forage.
So says Dan Undersander, a University of Wisconsin agronomist who spoke Saturday on the Dairy Forage Seminar Stage here at World Dairy Expo.
Expect lignin levels to decrease 5% to 15%, with the genetically-modified versions to decrease the most, he says. “The value of decreased lignin will be increased forage quality and wider harvest windows,” he says.
The lower-lignin alfalfa will allow for higher quality if farmers opt for their standard 28-30 day harvest interval, or greater total tonnage by going to a 35-day harvest interval and one less cutting.
For now, Undersander is recommending that farmers and growers take first cutting at the same time as conventional varieties. That’s because first crop, usually grown under cooler and less intense sunlight, tends to lodge the longer its left in the field.
After first cutting, Undersander says farmers can then go to the longer harvest window to get greater yield. Earlier studies show that overall yield will increase by about one ton/acre with the same quality as conventional alfalfa cut five days earlier. The yield advantage is about 17% in the second year of the stand and 25% in the third year. Plus, harvest and labor costs will decline with one fewer cutting. And winter survival might be greater since the plant is less stressed under a three-cut system.
Farmers may need to use fungicide more frequently with longer harvest windows, however. That’s because leaf diseases have longer to establish themselves and cause damage. So leaf loss could become a concern.
Additionally, once cut, the crop may have to be handled more gently to avoid leave loss. Mergers tend to be better than rakes because of the way they combine windrows. Tedders should be avoided because they can be pretty rough on plants. “Every pass with a tedder could reduce leaves by 5%,” says Undersander.
All the low-lignin varieties being offered for sale in 2016 will also be Roundup Ready. So there will be technology fees that will be assessed along with higher prices for the seed itself. “Low lignin alfalfa seed will not be cheap, but will be worth it,” Undersander says.