No-till and Cover Crops - Tips for Management
Cover crops may not seem like they are as important in a no-till farming system as they are for fields that are tilled. However, there are several reasons why cover crops are a vital part of no-till farming, especially on farms where the goal is to have continuous no-till.
Although no-till promotes good soil structure, soil must resist the effects of equipment traffic.
This is a challenge in today’s large acreage, heavy equipment operations.
Cover crops contribute to organic matter which is vital for good soil structure. They also produce food for earthworms and other life in the soil. A continuous no-till system relies on the life in the soil to keep the soil loose; doing the work that equipment does in tilled fields.
I think some of the best benefits of cover cropping is first to keep your soil covered, to keep something growing in your soil at all times. I strive to have something growing in all my acres all year round.
A growing crop on the ground helps to keep the microbes under the soil or in the soil, keeps them active and keeps them present in the soil, so that they’re ready to help your production crop such as your corn or soybeans that you want to be your cash crop.
A cover crop with good growth gives more support to the soil when driving heavy equipment over it.
This is particularly helpful in the late fall and early spring when soil is more likely to be on the wetter side.
We have already for those few loads of manure over the winter that you have to get rid of in the dead of winter on a really wet day and I’ve hunted a spot that was good enough to carry the tractor and spreader and I thought well here’s an old alfalfa field this might do it and it did not. We turned around and went out to the rye field and we couldn’t see any tracks. So if we’re not making tracks in the rye, if it is carrying the weight it probably is not compacting it. A good clump of roots will go a long way to help compaction and not only to keep it from getting compacted, but to break up compaction.
When you look at the ability to go out and, for instance run a piece of equipment over the top of that ground in the spring time, if you have a pretty healthy cover crop it helps to carry the weight of the equipment, whether it’s a manure spreader, a fertilizer spreader or even a lime spreader sometimes that can help to make the difference between a compacted track that’s difficult to work with, or no track at all. So a cover crop, if it’s well established, can help to carry that piece of equipment.
What I found is that the root mass that the cover crop gives actually gives support to the soil. And, so if you have bare ground even though it’s no-till, and over here you have a no-till field that has cover crops on and you go to spread manure or whatever activity you want to do on that ground especially if it’s a little bit too wet, the ground with the cover crop is going to take the weight of the equipment much better than the ground without it because it’s almost like a bridge system that you have the roots are giving you the support. Instead of all, on the ground doesn’t have that the soil has to support all the weight and activity on top.
A green, growing cover crop is able to absorb nitrogen in manure that might otherwise be lost to leaching.
I think that the cover crop retains a lot of the nutrients from the manure better than if they laid on open ground.
We haul a lot of manure and the cover crops will absorb that manure and sort of like a sponge, bring it and keep it on the, up toward the top where it belongs so it doesn’t leach.
We spread on cover crops in the fall and we spread on cover crops in the spring. We always have a root on the field, when we’re spreading manure and I think the plant and the root will store more nutrients than you save by working them in the ground and then when you’re tilling your soil you’re also subjecting your soil to more erosion which means you’re going to lose more nutrients. It’s my own belief that you’ll keep a lot more of your nutrients if you leave the soil alone and put it on cover crops.
Sometimes, other less obvious effects are discovered that help the no-till system work.
We had, maybe 7000 gallons per acre of dairy manure. We try to get that on maybe in early spring when we go to plant there the ground it would just remind you, it remained, kind of like the icing a cake. The manure just stayed there and you ran the planter through there and sliced it open and it made closing the trench difficult. I think it also, the manure kind of being harbored there held moisture on cold years and it was kind of hard to get started planting and I think it also led to sidewalk impaction of the seed trench. That rye cover crop that just breaks it right up and it grows through there and you don’t even really see it in a couple weeks of a growing, good, aggressive rye cover crop.
If you have a real lush cover crop, if you have a cover crop that has a decent growth on, that will actually even help with odor control because the manure will soak down through that and the cover crop itself will cover the manure. I’m talking liquid manure now.
So yeah there’s a benefit in that way too.