Tips for Successful No-till
Diesel fuel and fertilizer prices are soaring motivating farmers to look for ways to reduce costs.
This past year, many Midwest farmers started no-tilling to reduce fuel costs. With healthier soils, fertilizer costs should decrease. Healthy soils promote higher microbial levels. Each soil microbe is a soluble bag of fertilizer and your nutrient use efficiency improves, so less commercial fertilizer is needed. The soil has a huge bank of tied up plant nutrients just waiting for healthy soil microbial populations to release them to plant roots. Starting no-till is the first step.
Soil compaction is usually a big problem. Excess tillage and a lack of roots in the soil profile causes soil to lack the soil organic matter (SOM) to form healthy soil macro-aggregates. The roots form macro-aggregates with the help of soil microbes. The macro-aggregates store active carbon (glues for good soil structure), improve water infiltration, increase water storage. Micro-aggregates allow good gas exchange of air (oxygen) to roots and good respiration or carbon dioxide flow from roots to leaves for photosynthesis. Cover crops with deep roots (cereal rye, rye grass, sunflower, radish) can break up about one foot of soil compaction per year. Only use a deep ripper if the soil is very dry, otherwise the ripper smears the sidewalls. Higher SOM levels from no-till and cover crops hold up heavy equipment.
Nutrient stratification of phosphorus (P) and potassium (K) does occur but it is not a concern in no-till. With better soil structure and water infiltration, the nutrients move down to the roots. About 40% of a plant’s roots are in the top 6 inches of topsoil and another 30% in the next 6 inches. Fertilizer naturally stratifies in the top soil layers and is not a problem as long as a field has good soil structure. Forests and prairie have naturally stratified soils but very little nutrient runoff because they have high SOM and good soil structure.
Weed control is an issue in all fields. While Glyphosate (Roundup) is used on about 85% of all farms, clethodim (Select) is a good grass killer to kill cereal rye. Glyphosate is a major chelator of micronutrients and should not be used after soybeans start to flower. Herbicide trait resistance for 2-4D (Enlist), dicamba (Xtendflex), and glufosinate (Liberty) are all options to help control weeds. Dicamba helps control water hemp and Palmer amaranth but is highly volatile and may damage sensitive crops when it vaporizes.
On equipment, no-till farmers have little or no tillage equipment, but may need to do some modifications to their planters. Heavier bearings and harder, heavier disc openers may be needed versus OEM blades for better longevity and better residue control, especially in no-till and cover crops. Many farmers take the front coulter off because less down force is needed. The front coulter plus disc openers requires more down force than just using the disc openers to cut residue. This requires a sharp disc opener blades and they may need to be changed more often. Seed Firmers are recommended to improve seed-to-soil contact.
Due to higher crop residue, slugs and voles (field mice) are always a consideration in no-till and cover crop fields. Slugs and voles, however; are also commonly found in conventional tilled soils. It takes multiple practices to control slugs and voles. The biggest issue is avoid over using soil insecticides (on slugs) because that kills off the beneficial predators. On voles, perches and healthy predators (owls, American falcon, fox, coyotes) help keep vole populations under control. Good soil health and a balanced soil ecosystems of predators and prey can greatly reduce slug and vole damage damage.
Do biologicals work in no-till? That depends upon your microbial population and existing soil health. Many conventional tilled fields lack good mycorrhizal fungi (MF) populations and also good predators (protozoa and beneficial nematodes). The MF are good root extenders bringing back water, P, and micronutrients while improving soil structure. The protozoa and nematodes consume bacteria and other soil organisms, releasing tied up nitrogen (N) to growing plants. Biologicals can help get poorly degraded soils back in shape.
One of the first places to start is with a good soil test and good harvest data. Variable rate fertilizer can be placed in zones where it is needed to get better crop growth. Tillage often smooths out fertilizer applications but that does not happen in no-till. No-till often requires a little more N up front (especially on corn (40-70#/Acre). As you build soil health, the soil microbes also need and use fertilizer (N-P-K) to grow and can initially compete for nutrients until a balanced soil with good soil health is obtained.