Expert advice: What to do when your alfalfa crop fails

Grace Connatser
Wisconsin State Farmer
In this file photo, alfalfa weevil leaf injury is evident on these alfalfa plants.

Alfalfa plays a very important role on most dairy farms, and it's never good when the crop doesn't get a chance to grow in properly. But one expert says there's many alternative strategies you can turn to when it happens to you.

Tom Kilcer, who owns field research company Advanced Ag Systems, offered tips to farmers during a University of Wisconsin Extension webinar on Feb. 10. He said the forage you plant all depends on the season.

Kilcer grew up on a dairy farm in New York and has more than 30 years of experience in extension education and research at Cornell Cooperative Extension. He's a Certified Crop Advisor and Certified Pesticide Applicator and does private consultation for farmers in multiple states. His specialties include soil health and alternative forage crops.

During the spring, Kilcer recommends planting meadow fescue, oats and red clover in the alfalfa stand as soon as possible, also using a no-till drill. He said this mix of forage crops will not be affected by the old alfalfa crop and will take up nitrogen just fine.

The oats should be harvested at the flag leaf stage, which will help them last for another two years or so. Kilcer also said the red clover had better yields than alfalfa in one cutting during preliminary research and it also holds more sugar, making it quicker to ferment. However, producers should use an inoculant when cutting the crop to preserve the quality.

"You simply lay it out wet, let photosynthetic drying dry it and it will dry in one day. We had repeated research showing that we can consistently get it dry in one day, but it's critical that you dry it the day you mow it because of all those sugars," Kilcer said. "There's a lot of sugar there – it can grow on it, ferment it really quick. That's what preserves your quality."

Even cool season grasses will help raise yields in the fall. Kilcer said these are some of the best easy investments farmers can make because they're critical for increasing crude protein in forage and they should provide good amounts of nitrogen and sulfur.

For those short on corn silage, Kilcer suggested producers consider planting short-season corn around April and harvest in August, which will help reset the alfalfa rotation – or they can add it to the rotation permanently. He said sorghum is also a good alternative to corn that is high-energy, high-yield and grows well in cold climates. That's because sorghum doesn't need nearly as much rain as corn does.

Fields of grain sorghum, also known as milo, surround grain silos in southwestern Kansas.

"The big advantage with sorghum is when it turns dry, you can still get a crop," Kilcer said. "If we had one ton of corn being produced ... BMR forage sorghum will produce 70% more, 1.7 tons. Sorghum sudan BMR will produce 50% more, 1.49 tons. A non-BMR forage sorghum, which we use for heifers and dry cows, will always produce double the yield of what corn will under dry conditions."

When planting sorghum, producers are discouraged from planting it in wide rows, but instead in narrow rows that offer better stability and higher yield while also bringing in fewer weeds. Growers can use an omnidirectional harvester for that, Kilcer said. He added that sorghum is also good for the environment because it protects from soil erosion better than corn if planted in the narrow rows.

The brachytic dwarf variety of sorghum makes for a shorter, stockier and easier to cut plant as well, Kilcer said.

"But be careful if you switch to sorghum, because you'll need to heavily adjust your nutrition plan for your cattle, since sorghum is not the same as corn silage," he said.

However, in Kilcer's research, he found that he could feed cows more sorghum rations than corn silage rations because the sorghum lowered their neutral detergent fiber levels.

Overall, there was no difference in the milk whether they ate corn or sorghum, Kilcer said about his research findings. He also noted that balanced sorghum rations saved him $5,000 per 100 cows every year. Sorghum will also return savings because it only needs one cutting, saving both time and fuel. 

"(In my trials) sorghum, sorghum sudan and even pearl millet yielded significantly more in one cutting than it did in two cuttings," Kilcer said. "Out in Wisconsin, they found that they double the yield by doing a one-cut versus a two-cut, and that doubled yield was with less machinery costs. If you have to drive through the field twice to get the crop, it's a lot more expensive than to go through once."

Tom Kilcer

During the summer, Kilcer said any last-minute efforts for alternative forages can include triticale and oats if they're planted in August and harvested in October. He added that triticale will regrow through the winter and spring if cut at a height of least four inches in the fall harvest. That regrowth can then be harvested the following May.

Producers should make sure their oats are treated to protect from aphids that transmit disease, Kilcer also said. Oats can serve as a very high quality forage for the best cows in the herd because it clocks in at 17-20% crude protein and simple sugars >20% with sufficient sulfur and nitrogen. In his research, Kilcer said fall oats helped add 4,000 pounds of milk production per ton of oats.

Along with winter triticale, winter cereals can play two roles – as cover crops and forage. They help increase corn yields in the following seasons and reduce seeding risk while increasing yield. 

"It can help you offset when things go wrong and the alfalfa dies over winter," Kilcer said. "We used a bigger, one-ton dry matter reduction in corn yield. We are dropping that out now because the soil is so improved from the winter forage that we are getting 8-16% higher yield on our corn the next year."