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Cover crops in Wisconsin – Audio

Cover crops in Wisconsin - Audio

Matt Ruark, Assistant Professor
Department of Soil Science
UW-Madison College of Agricultural and Life Sciences
(608) 263-2889

3:01 – Total Time
0:13 – What are cover crops
0:28 – Popular uses
0:46 – Reasons to use cover crops
1:14 – What plants are used
1:58 – Research on cover crops
2:31 – More information
2:52 – Lead out


Sevie Kenyon: Learning about cover crops, we’re visiting today with Matt Ruark, Department of Soil Science, University of Wisconsin-Madison/Extension in the College of Agricultural and Life Sciences and I’m Sevie Kenyon. Matt, what are cover crops?

Mark Ruark: Cover crops are literally crops that are used to cover the soil. So these aren’t cash crops these are crops that are used in soil conservation efforts.

Sevie Kenyon: Matt can you give us some examples?

Mark Ruark: So the most popular way is for erosion control. So this would be on, for example, dairy farms that are growing corn silage so you have all of that corn stalk removal and you have exposed soil at the end of the year. There’s an opportunity for farmers to plant cover crops after that crops been harvested to get that soil covered. That’s just one of the reasons, there’s many other reasons as well, so there’s other people that are interested in using cover crops to reduce nitrogen leaching and protect ground water others; are using cover crops annually in an attempt to increase their soil organic matter and improve their soil health. And lastly, some farms are using cover crops to supply nitrogen. So, using it as an organic fertilizer.

Sevie Kenyon: Can you give us an example and some ideas of what kinds of plants are used in cover crops?

Mark Ruark: I break this down into three categories, there’s grasses, there’s legumes, and there’s brassica. So, the grasses are rye, oats, spring barely, anything that will establish quickly and provide good erosion control. So, the legumes are used to supply nitrogen they don’t grow as fast, but when they decompose they release a lot of nitrogen to that next crop and lastly, are the brassicas and those are the deep rooting, radish, cover crops or sometimes you’ll see turnips. But, those are used by farms that they want to get roots really deep into the soil profile to help with some water infiltration or to break up some compaction in the subsurface.

Sevie Kenyon: Matt, what kind of research do we have supporting the use of cover crops?

Mark Ruark: We have a very robust research program here at UW-Madison on cover crops. We’re investigating the benefits and potential drawbacks of using the grass cover crops following corn silage and we’re also evaluating the benefits of the legume cover crops in terms of supplying nitrogen and potentially increasing yield. One of the more innovative things that we are working on and working with farmers as well, is how to inter-seed cover crops. That means we are planting the cover crops while that cash crop is going, it’s become very popular among grain farmers.

Sevie Kenyon: And Matt, if somebody is interested, where can they get more information?

Mark Ruark: For more information, you should check out our soils Extension webpage, as well as our Discovery Farms program that hosts not only information but also the WaterWay Network, a forum designed for farmers to interact with other farmers and discuss successes and concerns about cover crop use.

Sevie Kenyon: We’ve been visiting with Matt Ruark, Department of Soil Science, University of Wisconsin-Madison/Extension in the College of Agricultural and Life Sciences and I’m Sevie Kenyon.