Building Soil Health for 44 Years in the United States
Cheick Saidou /
A text from David Brandt

In 1971 I had a young family and was farming 750 acres using a rotation of Corn, Soybeans and Wheat. I operated a 300 sow farrow to finish operation and managed a 50 head Charolais cross beef herd using 80 acres of pasture. I was also active in the farming community and with my church congregation. All of these commitments gave me the ability to begin using no-till practices as I no longer had the time for tillage. In 1978 I was able to purchase my grandfather’s 80 acre farm. It had been in continuous tillage corn and beans rotation for 30 years. Most of the fertility had been taken out of the soil. It contained 0.5% Soil Organic Matter (SOM) and was in serious need of added fertility and drainage tile. This farm and my other acres, even with No-Till practice, was loosing 6 ton of soil per acre per year due to erosion, either water or wind. I began to look at ways to increase surface residue during the winter and spring to minimize this loss and help build SOM. With my current practice of 100% No-Till, a strict rotation of Corn Beans and Winter Cereal and growing Cover Crops between Corn and Beans and Winter Cereals and Corn soil erosion is reduced to less than 100lbs/Acre per year and SOM has increased to 8%.

Getting started in Cover Crops was frightening, but I was accustomed to doing things differently, something I had learned from my parents and grandparents, who were resourceful people. Cereal Rye was the first cover crop used between Corn and Beans. The Rye helped to dry out my wet clay soils in the spring, and the residue helped hold moisture in in the late summer heat. Over the years I have been able to maintain 5 to 10% higher than state average yield when using cereal rye in combination with a sound fertility maintenance program. Today we use modern planting equipment with managed traffic to minimize compaction, but the principle is the same. We have added the use of the roller-crimper to minimize herbicide use and lay the rye flat. Although not necessary for soybean health, the flat residue does reduce stress on the beans as they emerge and grow. The roller crimper is a useful tool that is gaining popularity in America as more learn about its versatility. It can be very helpful for small plot farmers, especially vegetable growers, and even an economical version, the “poor man’s crimper” can be made from a board with a piece of angle iron attached that is very effective.

Erosion was a greater concern, along with weed control, in wheat stubble going to corn. To stabilize the hills I would plant Hairy Vetch , Winter Peas, or quite often “greedy beans” or double crop soybeans. Peas and Vetch remain two of my favorite covers to use in blends, as the nodules (“fixed” Nitrogen) can be found throughout the soil layers to aid corn emergence, grain development and added test weight.

Introduction to the Daikon Radish opened my eyes to new possibilities and a beginning understanding of what cover crops are doing for soil health. Planting peas and radish together with a precision planter not only gave greater economy to seed cost, but increased the effectiveness of either compared to planting alone. The radish not only lifts and opens the soil, it retains soil nutrients that may have been washed away in the winter, helps to reduce soil borne pests and attracts earthworms. The quick growth of radish and large biomass suppresses weeds so there is a reduction in the need for herbicide the following year.

As I began to look at mixes of cover crops that included 4, 6, 12 or more species I began to notice greater synergies between the different seed types. Having several different types and classes of plants gave resiliency and larger plants than single specie plots I was observing. Cover crop mixes can be designed to provide Nitrogen and increase SOM. We have shown high carbon mixes to increase SOM by more than 0.5% per year. This is very exciting due to the amount of carbon sequestering taking place and the ability of the soil to provide more of the fertility needed for crops as opposed to adding synthetic fertilizer.

If this is so great, why is it that very few are doing it? Several reasons beyond resistance to change and fear include climactic challenges and manpower shortage. The use of cover crops and using conservation agriculture practice requires much planning. The timing of seeding cover crops is very important, and it  usually coincides with harvest, when weather conditions turn unfavorable quickly; and manpower is dedicated to harvest, not planting cover crops. Innovative farmers find ways around this. In the United States several farmers developed air seeders based on a high clearance sprayer platform. Others mounted air seeders on their harvest equipment and get two jobs done at once. Others are looking at seeding companion crops with corn or sunflowers that do not interfere with harvest, but are beneficial in that they provide Nitrogen or suppress weeds.

In the United States, the Natural Resource Conservation Service has several excellent programs and employees that promote Conservation Agriculture, specifically the transition to minimal Soil Disturbance  and the use of cover crops. Although a National program, the adoption is more of a grass roots effort, with the focus on personal interaction and mentoring between the experienced and those starting or wishing to change to conservation practices.

David Brandt farms 1,100 acres in central Ohio's Fairfield County. He began no-till farming in 1971 and has been using cover crops since 1978. David has participated in yield plots for corn, soybeans and wheat into various covers. This information has been used by seed growers as well as county agents and universities to encourage other farmers to adapt no-till practices in their farming operations. He has also been planting various blends of cover crops to find out what benefits they provide to improve soil. At present David is working with Ohio State University's Randall Reeder and Rafiq Islam on reducing input costs of fertilizers and herbicides using various cover crops, which improve soil health. He is also working with the regional Natural Resources Conservation Service (NRCS) soils lab in Greensboro, N.C., on the benefits of cover crops to improve soil health. David has received numerous awards for conservation practices, including the Ohio Conservation Educator Award from the Ohio No-Till Council, Ohio State University South Center's Supporter of the Year, Ohio Agriculture's Man of the Year, the Ohio Farm Bureau Federation Distinguished Service to Agriculture Award, and Ohio NRCS Soil Conservationist Partnership and State Volunteer Awards.

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