Ask Fennig Equipment about Planting Cover Crop!
Making No-till Corn SuccessfulNo-till corn production has struggled to be successful in the Midwestern United States. No-till farmers say it takes 7–9 years to transition from conventional farming to long-term no-till. Using a cover crop with continuous long-term no-till shortens the time period to 2–4 years. No-till corn yields are typically reduced 10–20% during those transition years.
This occurs for several reasons. First, initially fewer nutrients are being released from the residues deposited on the soil surface. Tillage allows surface residues to decompose faster, releasing nutrients, but it also destroys organic matter, resulting in less storage of soil nutrients.
Second, in biologically active soils, the microbial biomass is increasing in size and population, accumulating N as amino acids and proteins and P as DNA in microbes. This initially deprives no-till corn of nitrogen and soil nutrients until the soil system becomes stable.
Third, the soil is building humus organic matter, which requires N to decompose and stabilize the organic molecule. Every 1% SOM requires 1,000 pounds of N, so if the N is being tied up and N is not available, the soil microbes will utilize N before the corn. Fourth, soil compaction from the previous tillage causes denitrification from saturated/ water-logged fields, losing 40–60% of the available N in the soil.
So to reverse this process, first cover crops are grown to reduce soil compaction and improve the recycling of C and N in the soil. Second, as the microbial and humus organic matter levels build up, N and P are more efficiently recycled in the soil to the corn and no-till corn yields increase, outperforming conventional tilled soils. Third, as water infiltration increases and soils are better aerated, denitrification and N losses decrease, increasing the storage and recycling of N in crop residues and organic matter (humus) and resulting in more soil nutrients (N, P, and S) for the corn crop. See OSU Extension fact sheet Understanding Soil Ecology and Nutrient Recycling.
Reasons Why No-till Corn Struggles
1. Surface residue ties up nutrients and slows down decomposition and release of nutrients.
2. Soil microbes tie up soil nutrients, especially N.
3. Long-term soil organic matter ties up nutrients, especially N.
4. Compaction and poor drainage causes denitrification and loss of N.
5. Cold wet soils limit germination and planting.
Successful No-till Plus Cover Crops
1. Reduces soil compaction.
2. Improves C, N, P recycling.
3. Reduced N Losses from denitrification.
4. Increased nutrient storage in soil from increased SOM
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