Keith Berns and his brother Brian co-own Green Cover Seed and Providence Farms in Bladen, Nebraska where their family has been farming for over 100 years. They farm 2,500 acres including corn, soybeans, rye, triticale, peas, buckwheat, and sunflowers using continuous no-till and a variety of cover crop strategies to maximize the health of their soil.
In 2007, the Berns brothers founded Green Cover Seed to fill the demand they saw for cover crop and forage seed mixes. Since then their business has grown exponentially, becoming one of the major cover crop seed providers and educators in the United States. They have helped pioneer the use of customized cover crop cocktails with their innovative SMARTmix CalculatorTM. This online decision-making tool uses geographic and climatic data combined with user-provided planting dates and goals to help farmers decide which blend of cover crop seeds is best suited for their purposes. Green Cover Seed has experimented with almost 100 different cover crop types and hundreds of seed mixes planted into various situations. Their deep commitment to improving soil health can be witnessed in their education and outreach at conferences across the country, as well as in their research on the growth, nitrogen fixation, moisture usage, and grazing utilization of cover crops.
In this video, Keith Berns describes one of his cover crop strategies that consists of using a cocktail of about ten different companion plants interplanted with a cash crop. His goal is to never see the soil unless he goes looking for it. He protects his soils by having living roots in the ground all year round and by leaving plenty of residue behind after harvesting. In this example, he shows us a field with a healthy thatch of triticale straw, into which he has planted a mix of cover crops along with his cash crop, sunflowers.
Some of the cover crops used in this mix include cowpeas, Austrian winter peas, flax, buckwheat, and squash. This assortment of cover crops provides him with a variety of soil benefits such as nitrogen fixation, nutrient cycling, and water infiltration, along with increased soil structure, organic matter, and biological life. In addition, this colorful cocktail of plants provides all of the added benefits that come with biodiversity, including increased productivity, resilience, and sustainability.
Since the sunflowers grow above the cover crops, he will be able to harvest those flower heads for their oil, leaving intact the cover below to protect the soil until the next round of planting. In this way, he is able have his cake and eat it too, by simultaneously receiving the benefits of cover crops while still being able to harvest a cash crop.
Sunflowers have massive root systems. Roots help build soil and give it structure while providing an environment for soil microorganisms. Earthworms love sunflower roots. They leave channels as they burrow through the ground, which act as conduits to bring moisture into the ground. This porous network paired with a thatch of residue makes this field able to absorb a big rain while limiting erosion. The earthworms also help by grabbing pieces of straw or leaves and pulling them underground into their channels, which speeds up decomposition and nutrient cycling.
Earthworms are the easiest part of the soil biology to see, but there are countless other microorganisms that are too small to see that play a very critical role in soil and agriculture. Soil may appear lifeless to the naked eye, but in fact it is full of biological life- we just can't see most of it. By keeping the soil covered with crop residue or plants, growing a diversity of crops, and disturbing the soil as little as possible through no till practices, we can help protect our soil microorganisms and preserve our living soils for years to come.