Mark

Nov 03 2020

An Excellent Cover Crop Mix Ahead of Corn

The mix pictured above is Nutribuilder Mix. It’s a three way mix of annual ryegrass, clover, and radishes.

This field was planted on August 18 at 25 pounds per acre. The included pictures were taken on October 30. The plan is to plant this field into corn next year.

The growth in this field shows the importance of a timely planting date. This is especially important for the radishes, since they will winterkill – and the farmer will want maximum benefit from them before they die.

Benefits

Each component in this mix will enhance the performance of the soil and improve the productivity of the following year’s crop. And of course, the long-term benefits associated with the ongoing use of cover crops are hard to quantify.

But what are some specific things to expect from each of these components?

Annual ryegrass

Annual ryegrass provides one of the best cost-to-benefit ratios of any cover crop, maybe the best. It’s inexpensive, versatile in application (aerial, broadcast, drill), and provides tremendous value to the soil. Annual ryegrass breaks up compaction, allowing better water infiltration. The depth of the roots provide access to parts of the soil previously unavailable to the cash crop. The fibrous root system near the soil surface helps prevent erosion. Annual ryegrass is an excellent scavenger of leftover nutrients, holding them for use later in the growing season.

Crimson clover

Crimson clover is an excellent choice for building nutrition into the soil. If you’re looking to build nitrogen for your cash crop, crimson clover provides that service. Since it will survive the winter, it will provide biomass as well. The crimson clover will also help the annual ryegrass and radishes to grow bigger and provide more benefit to the soil as well, as demonstrated by this video.

Radish

Cover crop radishes have been the super stars of the cover crop world. Their benefits have been noted over the years. They:

scavenge nutrients from the soil (especially nitrogen).
penetrate the soil, therefore reducing compaction.
enhance soil percolation and aeration.
provide an excellent environment for earthworms.
provide deer and cattle an excellent wintertime feed.
die in the winter.

Conclusion

Taking all of this information into consideration, this type of mix is an excellent choice to plant in the fall before planting corn the following spring. Keep in mind that only the radish will winterkill, so you will need a plan to terminate both the annual ryegrass and the crimson clover.

Jun 12 2010

Austrian Winter Peas

Austrian Winter Peas are a good cover crop for producing nitrogen. These peas have better cold tolerance than Canadian Field Peas yet still grow well when planted after wheat or other summer annuals. It’s preferred to plant them in August after the hottest days are normally past. Below I list the advantages and disadvantages of Austrian Winter Peas.

Cover crops May 2010 031 — Austrian Winter Pea flower

Cover crops May 2010 077 — The peas in my garden plots overwintered and grew to over 5 foot tall this spring!

Groundbreaker-peas — Austrian Winter Peas provide a very nice source of Nitrogen.

Advantages

Produces 60-120#/acre N
Generally Winterkills
Easy to kill with herbicides
Mixes very well with Oilseed Radish
Relatively inexpensive to use as a cover crop

Disadvantages

Best to be planted 1/2″ or so
Aerial application provides challenges for stand establishment- but has worked!
Generally Winterkills
Needs 5-6 weeks growth for best results
Only one grazing/harvest can be expected

Jun 12 2010

Cover Crop Selection – What to plant after wheat or other cereal grains?

I was in a meeting yesterday and the gentlemen from SWCD asked me:

“What should we recommend for our producers to plant as a cover crop after the wheat comes off?”

After running through a number of scenarios I determined that I’d better make sure I don’t confuse folks with too many ideas. So, here are a few scenarios that I hope you find useful.

If you want to scavenge Nitrogen and other nutrients, then a good choice would be Oats and Radishes mixed together. This mix generally should be planted at 1 1/2 bu Oats and 2-5# of Oilseed radish/acre. This mix also requires manure or around 40# N applied for it to be the ideal mix for this situation. This mixture will die in the winter and provide excellent winter annual weed control. Best planting time is Mid August…so you have plenty of time to get weeds killed and manure applied.

2009_0909earlySept20090256 — Sudangrass and Sorghum-Sudangrass are excellent crops after wheat if you need animal feed.

If you have livestock to feed, other great nutrient scavengers to plant after wheat are Sudangrass, Pearl Millet, or Sorghum-Sudangrass. These summer annual grasses require 100+# of N or equivalent manure. Tonnage of 4 1/2 tons Dry matter/acre have been common in northern Indiana following wheat the past three years. These grasses are excellent soil builders as well. Mycorrhizae fungus find the roots of these plants a very good place to multiply and build soil structure.

2009_1213December20090049 — Oats and Radish Mixture following wheat. Hog manure was nitrogen source.

2009_11172covercropsfall20090507 — When properly inoculated, Austrian Winter Peas are prolific producers of nodules (and nitrogen).

2009_11172covercropsfall20090483 — Oilseed Radishes are "nutrient sorage facilities"! These big tubers take in significant amounts of nitrogen and other nutrients.

If you want to produce nitrogen and also scavenge nutrients as well, then an excellent choice will be Austrian Winter Peas mixed with Oilseed Radish . This mixture works very well without the addition of additional nitrogen. Count on the peas to deliver 60-120# of N and the oilseed radishes to keep most all of it in the top soil root zone. This mixture does a great job of controlling weeds. The radishes will die in the winter and the peas will “probably” die too…depending on your location, planting time of the mixture, and snow cover. If they overwinter they are easily killed in the spring.

If you are looking mainly for nitrogen production with a species that will winterkill, then choose cowpeas. The past few years cowpeas have been very expensive to plant. Be sure to check pricing and also be sure to inoculate the seed at planting time. Sow 60-100#/acre of cowpeas.

If you want the nitrogen production with a crop that will overwinter, then crimson clover is a top choice. Excellent new varieties have come on the market the past few years. Be sure to inoculate this seed as well. Sow 20-25#/acre of crimson clover.

Cover crops May 2010 010 — Crimson clover planted after wheat is an excellent nitrogen producer.

There are several other options but these will certainly give you a good start in making selections.

Jun 06 2010

Cover Crop Radishes – What they do

2009_11172covercropsfall20090124 — Cover Crop radishes drill deep into the top soil. Some claim that they break through the plowpan.

Cover crop radishes are “all the buzz” these days in the cover crop world. Cover crop radishes should have fairly large tubers that penetrate the soil and add many benefits. The main benefits are that they enhance percolation and aeration. Additionally they provide food for earthworms like few other cover crops. It is quite common to find 3-5 earthworms per tuber.

2009_11172covercropsfall20090511 — Larger tubers of cover crop radishes "lift" the soil around them, "building" the soil. Note the smaller radish to the right...it is also an effective soil builder.

The question that many producers and researchers are asking is “how big” do the radishes need to be to be effective? My friend Barry Fisher, NRCS Agronomist in Indiana, leans towards several smaller tubers being better than the “State Fair” type that may be confused for a baseball bat! While the larger tubers make newspaper ads and are great for photo ops, I’m not convinced that they are necessary. On the other hand, the larger tubers do a better job of “lifting” the soil around them. It is not uncommon to find soil built up around the larger tubers at least 1/2″. (See photo)

Old radish hole — A hole where a radish tuber had been. Note the lifted soil!

Cover crop radishes scavenge nitrogen and other nutrients from the soil. To achieve the larger tubers it is important to have good fertility like manure or a legume planted with the radishes. If there are few nutrients to scavenge, the radishes will rarely become very large.

The main benefits of cover crop radishes

Cover crop radishes:

scavenge nutrients from the soil (especially nitrogen).
penetrate the soil, therefore reducing compaction.
enhance soil percolation and aeration.
provide an excellent environment for earthworms.
provide deer and cattle an excellent wintertime feed.
die in the winter (around 25-29 degrees).

Cover crop radishes may also:

increase yields on corn by as much as 9-10 bu/acre (recorded in central Indiana).
reduce soybean cyst nematode populations.
improve control of winter annual weeds (this is usually the case).

When planting cover crop radishes:

Drill 1-3# or broadcast 3-5#/acre for larger tubers.
Drill 3-5 or broadcast 6-10#/acre for more, smaller tubers.
Use improved selections (varieties) for more consistent results.

The main detriments of cover crops radishes

Cover crop radishes:

stink when they deteriorate!
may head out if you plant them too early in the summer. A late-summer planting (August-September) works best.
need 6-10 weeks of growth for best results.
may contain hard seed, which when sown in the late-summer, may germinate in the spring.
may develop very deep roots in very sandy soil…which may get into field tiles…even 32″ deep tiles

Jun 05 2010

Earthworms…valuable resource on farm ground

Earthworms are exceptionally valuable builders of healthy, fertile topsoil. Jill Clapperton stated that a good sign of a healthy topsoil was that a “shovel-full of soil” should have 8 earthworms in it. In my field diggings I have found anywhere from ZERO to 10 erathworms per shovel-full. I found 10 in crimson clover, 8 in annual ryegrass, 7 in my Austrian winter peas, 10 in my annual ryegrass/crimson clover mix and ZERO where I had no cover crop.

An Excellent Cover Crop Mix Ahead of Corn