Cover crops will make you a better farmer, but don’t let them cost you yield.
That’s the message Real Agriculture agronomist Peter Johnson wants to deliver as he surveys a growing body of cover crop research.
In this video, Johnson touts the benefits of cover crops – from better soil health and increased organic matter, to reduced weed seed populations. But he also cautions farmers to be aware of the potential weed problems and the yield impact when planting into green cover crops.
Johnson is excited about research from OMAFRA weed management lead Mike Cowbrough showing cover crops can reduce weed populations by up to 99%, but he says farmers have to be careful when including crops like buckwheat and sunflowers in multi-species cover crop mixes. If these go to seed, they can pose competitive weed problems in following crops.
Johnson adds that farmers need to be wary of planting into green cover crops. He’s still compiling 2016 research, but trials on his own farm showed 25 bushels per acre less yield when corn was planted into a green multi-species cover crop versus planting into no cover crop or an oat/pea crop that died over the winter.
His recommendation? “If you have a multi-species cover crop, you make sure you kill it, either this fall or early, early next spring.” He offers the same advice for farmers who planted cereal rye in corn stalks this fall.
Johnson maintains his love for cover crops, but says farmers need to proceed with some caution. “We don’t want you to lose yield. Once we figure this out, cover crops will make you a better farmer.”