A note about why and How! For the soil to absorb and hold water, there needs to be lots of humus and the associated growth of microorganisms. I just want to note that the oat-field pea combination will give 18 inches of root growth in less than 60 days and can be done at many times of the year. Just a little background to help farmers get started.
From the USDA:
“On fields growing corn for grain, one of the most commonly grown commodity crops, 0.6 percent of the acreage used a fall cover crop before the 2010 crop. By 2016, 5.5 percent of corn-for-grain acreage had a preceding fall cover, and by 2021, 7.9 percent of corn-for-grain acreage followed a fall cover crop.”
Even less acreage was utilized on soybean fields, and I don’t know about cotton, wheat, oats, and other cash crops. But 7.9 percent is a low figure. I want to know why. If you read my last article; “Regenerative Agriculture--Drought all around, but I have water! == PART II”, you would have seen a number of financial reasons to start. I want to know why cover crops are not more widely spread in the US of A.
My brother farms and we have had some discussions about utilizing cover crops in his farming operation. His son farms the land and it is a corn-soybean two-year rotation. He informed me that some of the neighboring farmers have, using airplanes, spread cover crops seeds. So far, their success ratio has been a failure due to the lack of moisture available to germinate the seed in the fall.
How do you get started with Cover Crops? Less than 8% of the farmers are utilizing cover crops. Cover crops are not Regenerative Agriculture. They are an important part of the system, and most farmers will start with cover crops.
When I first heard of cover cropping, my impressions were that the cover crop would be for the times when the grain had been harvested and the land lay fallow. This would mean July, Aug. and Sept for Kansas wheat farmers. But MO corn farmers would have fallow ground in Oct, Nov. Dec. Jan. Feb. March, and most of April. The most important part of the cover crop is to nurture the soil and provide food for all those microorganisms living down there year-round. Having a good root supply and mulch above the ground will give the soil feed to survive. Many of the cover crops will winter kill, yet they have served their purpose in nurturing the soil. With this in mind, look at the alternatives:
My brother gave me a plot of land to see if I could demonstrate how it could be done. The plot is 1.1 acre (farmers usually know in detail about their operation). It is fall now with the soybean crop almost ready to be harvested. I will be using a hand seeder which will broadcast the seed similar to the effect of a plane flyover. No chemical spray will be used. I don’t know what seed for cover cropping has been used by the other farmers in the area. I will lay out a plan that can be tried, but each farmer must be able to adjust according to the weather. My plan will show options, but I will keep Daily Kos informed of the actual results. Now the plan:
For fall over-seeding with a cover crop, annual rye following a corn crop is considered one of the best choices. A second choice would be hard winter wheat. Both of these grass-like crops produce lots of straw for a spring mulch. Many times, they will have a companion crop as the more different plants grown, the wider the distribution of various microorganisms. I will be using the wheat because I can use a full bushel for an acre, If I used rye, I would spread it over several acres and it would be cheaper than wheat per acre, but since it is more expensive per bushel, I would have lots of seed left over from my experiment on just one acre. At the present date (last of Sept), it is dry and there is no outlook for rain in the near future. The wheat can be planted as late as the last of Oct in this area. If we don’t get rain, I will go to the second option.
COST 15 to 18 dollars for wheat. (This is a half rate as we will be inter-seeding in the spring. Another option is annual rye which is more expensive, but because it is spread thinner, is actually around 8 dollars an acre)
NOTE: As I write this, moisture is a problem and since a dry spell is predicted for the next two weeks, I will go to option two.
------------------------------------
In the last week of Feb or first week of March, we could frost seed Fixation Balansa Clover. This clover will frost seed and in 60 days will produce 3 ft high plants. The plants are actually up to 8 feet tall, but won’t stand up more than 3 feet. They produce a tremendous amount of mulch as well as nitrogen. If I had a rye or wheat stand this clover would be inter-seeded into the wheat unless we don’t have a stand of wheat, then we will double the application rate. This is an option I will not use as the no-till planter that will be used for planting would need some adjustment to keep from clogging with excess growth. For just an acre, it would not be cost-effective. The adjustment to the planter is minor. So I will go to the third option for the one acre experiment.
NOTE: Red Clover and Crimson Clover are other clovers that will frost seed well. Frost seeding is the spreading of seed when the ground is alternating freezing and thawing. The action of the soil brings up moisture and will draw the seed into the ground for germination.
Cost 6 lb 20 dollars per acres for any of the clovers.
More about FIXatioN Balansa Clover: Bio-Massive Clover Seeds
picture from; https://www.outsidepride.com › seed › fixation
- “Capable of setting more than 100 units of Nitrogen per acre
- Large amount of high-quality biomass increases soil organic matter with a thick mat of organic mulch
- Growth of up to 3ft high with stems up to 8ft long suppresses spring weed growth by shading the soil and out-competing weeds for water and nutrients
- Deep tap root breaks up soil compaction
- Increases the water-holding capacity of soil
- Bio-massive growth and root system shades soil and prevents erosion and run-off
- 18" of root growth in just 45 days”
-----------------------------------------
The third option which will work for any program that fails to get a fall cover crop or the early spring frost seeding by airplane or spreader.
In mId March, sow peas and oats…This can be done if the fall planting or frost seeding was not made or failed to grow. Will produce 100 lbs of nitrogen in 60 days. COST for sowing 100 lbs of seed is per acre-- $50.00.
This crop will be ready to be terminated in about 60 days. Most cover crops will produce the most nitrogen when terminated during seed blooming stage. They should be terminated before making seed to prevent regrowth as a possible weed. Except for those cover crops sown so that they will winter kill, they must be terminated. One option is to use a spray before planting which will kill the plant and is what most farmers do now to clear their land before planting. You have probably seen the brown fields early in the year if you travel in the country. This prevents having to plow or disk to kill volunteer weeds that sprout each spring. A good alternative which saves on money for toxic chemicals and can be used to convert your land to Organic, is a roller crimper. This machine is either pulled behind the planter or ahead of the tractor pulling the planter which means only one trip across the field. It is a heavy roller with groves and as it rolls over the cover crops breaks off the stem at soil level leaving the biomass lying flat as mulch.
Most cover crops can be grazed without hurting the nitrogen content, but grazing would need to be limited to allow for the accumulation of mulch on the surface of soil. Ideally, the corn would be planted 2 weeks after the cover crop is rolled down to allow for the cover crop to start decaying and providing nitrogen as a starter for the corn crop. Studies have shown that planting corn two weeks later does not influence yield.
---------------------------------------------------------—
Another option is to inter-seed the corn crop. This can be done when the corn is about knee high. But, this can also be done even if you already have a cover crop program going during the fall or early spring. It will allow additional cover, nitrogen fixation and will produce a cover crop for fall without reseeding.
When corn is 12 to 18 tall, with a spreader attached to the tractor (or flown over), the tractor will be able to clear the corn stalks, seed radishes ( or any warm season cover crop) in the middle of rows. Seed radishes by their self as they will crowd out any companion crop. The interseeded cover will start to grow, but as the corn shuts off sunshine to the ground, shade will stop their growth and then the cover crop will restart when corn is harvested.
COST 3 LBS 10.00 DOLLARS
After corn harvest spread annual rye if needed.
COST about 8 dollars
At any time in the spring, spread dutch clover. The clover will grow in the row and when fall comes, you will already have a cover crop.
COST 2 lbs $20.00
There are lots of other cover crops that can be substituted. depending on when you want to plant and when moisture may be better.
--------------------------------------------
After the fall harvest of corn, you will need to adjust your cover crops for the next year bean crop. You can continue with cover crops as with corn, but you cannot plant just any crop on the beans while they are still in the field. Many of the cover crops may, before harvest, grow tall enough to interfere with the harvesting. You can over-seed with Dutch clover as it will not grow tall enough to interfere when combining. This can be done at any time and would take some of the worries about scheduling. Again, this may be flown in when moisture is available, and leaves are starting to drop to allow sunlight to reach the sprouting crop
Once cover crops has been started, the mulch and growth below the surface will retain a lot of moisture. The soil will cease to crust over and will have lots of openings for the seed to drop into which will allow it to be closer to moisture. The mulch will allow moisture to migrate toward the top of the soil without escaping and be available for seed germination.
As you can see, at almost any time of the year, you can start the program, you just have to worry about a preemergence spray from a previous crop that would keep stuff from germinating. Many farmers use a knockdown spray instead of a roller, but this will delay organic certification and will cause harm to the soil. If you have a good stand of mulch, it will stop weeds. In addition, the cover crops have a beneficial effect on disease, insects and other crop problems.
There are some limitations from the government on cover crops even though they will pay for their use. ‘Additional expenses will be a roller-crimper. Compared to other farm equipment, they are inexpensive. If you take into consideration the savings from fertilizer, extra seed costs, spraying and other planting costs, the savings will more than pay for this one-time cost.
We have a list of seed sources for Cover Crops on our website which can be found HERE
A good chart for Ia but applies to others;
Cover Crops for Iowa
Winter Hardy Grains
- Cereal Rye • Winter Wheat • Triticale (cereal rye and winter wheat cross)
Seeding Dates Aug. 15 - Oct. 15
Seeding Rates 1-2 bu/acre
Seeding Depth .5 inch to 1 inch
Establishment Drilled, No-till, Broadcast with incorporation; Broadcast at leaf drop (bean)
Best Use Good fit following corn silage, before beans harvest and grazing forage for livestock (avoid compaction in wet springs) •
Best Use Management Information
Minimum of 8 inches of growth recommended before spring kill to ensure adequate residue.
- With the additional spring growth, rye will produce four times the dry matter as oats.
- Kill rye two weeks prior to planting corn to minimize allelopathic effect.
- Timing of kill not as critical when planting beans.
- Triticale not as winter hardy.
- Aerial application in standing corn not recommended.
- Seed slots may not close if rye cover crop is still green at planting.
- Excellent weed control.
- Need N at planting of intended crop to offset the effect of soil microorganism N tieup.
Winter Killed Grains •
Oats •
Seeding Dates Spring Wheat Aug. 15 - Sept. 15
Seeding Rates 2-3 bu/acre
Seeding Depth .5 inch to 1 inch
Establishment Drilled, No-till, Broadcast with incorporation; Broadcast at leaf drop (bean) Best Use Management Information
Fallow or prevented planting acres; corn silage
- Spring kill not required for oats.
- Oats produce no allelopathic affect for following corn crop in the spring.
- Minimum of 6 inches of growth needed before winter to ensure adequate residue for erosion control.
- Less nitrogen scavenging than winter grains.
- In dry years, less chance of using up available moisture for intended crop.
- Need N at planting of intended crop to offset the effect of soil microorganism N tieup.
Winter Hardy Legumes • Hairy Vetch • Red Clover • Sweet Clover
Seeding Dates Aug. 1 - Sept. 15
Seeding Rates 8 to 15 pounds/ acre
Seeding Depth .25 inch to .5 inch
Establishment Drilled, No-till, Broadcast with incorporation; Broadcast at leaf drop (beans)
Best Use Management Information
Good fit after corn silage in a corn on corn rotation; fallow or prevented planting going to corn; in beans at leaf drop
- No allelopathic effect for corn.
- Potential N source for following crop.
- Sweet clover has the greatest potential for N fixation.
- Kill timing not as critical when going back to corn.
- Not recommended prior to planting beans.
- Less winter hardy if planted late in fall
Forage Covers (winter killed) • Turnips • Rapeseed • Radishes
Seeding Dates Aug. 15 - Sept. 15
Seeding Rates 5 to 15 pounds/ acre
Seeding Depth .25 inch to .5 inch
Establishment Drilled, No-till, Broadcast with incorporation; Broadcast at leaf drop (bean)
Best Use Management Information
Grazing forage for cattle or deer
- Good at suppressing nematodes and weeds.
- Good N scavengers.
- Excellent fall/winter forage for domestic livestock and wildlife.
- Good at reducing compaction.
Forage Covers • Turnips • Rapeseed • Radishes
Seeding Dates Aug. 15 - Sept. 15
Seeding Rates 5 to 15 pounds/ acre
Seeding Depth .25 inch to .5 inch
Establishment Drilled, No-till, Broadcast with incorporation; Broadcast at leaf drop (bean) Best Use Management Information
Good suppressing of nematodes and weeds.
- Good N scavengers.
- Excellent wildlife winter forage area.
- Good at reducing compaction.
For more information, there are charts on the left sidebar of Urban Homesteading
Please follow me on www.dailykos.com/...