Source: Ohio State University
By: Peter Thomison and Steve Culman
In the quest for high corn yields, considerable attention has been given to increasing various inputs, including seeding rates and fertilizers, narrowing row spacing, and making preventative applications of foliar fungicides, growth regulators and biological stimulants. However, the significant drop in crop net returns that’s occurred in recent years warrants developing strategies to lower input costs. An input that might have paid for itself with $5.50/bu corn may not at $3.75/bu corn. A practical and economic approach to achieving high yields is to follow proven cultural practices that enhance corn performance.
1.Know the yield potential of your fields, their yield history, and the soil type and its productivity.
2.Choose high yielding, adapted hybrids. Pick hybrids that have produced consistently high yields across a number of locations or years. Select hybrids with high ratings for foliar and stalk rot diseases when planting no-till or with reduced tillage, especially after corn. Select high yielding Bt rootworm resistant hybrids where is potential for the western corn rootworm damage.
3.Follow pest management practices that will provide effective, timely pest control – especially weed control.
4. Aim to complete planting by May 10. If soil conditions are dry, begin planting before the optimum date but avoid early planting on poorly drained soils. If planting late (after May 25 in central Ohio) plant corn borer resistant Bt hybrids.
5.Follow practices that will enhance stand establishment. Adjust seeding depth according to soil conditions and monitor planting depth periodically during the planting operation and adjust for varying soil conditions. Make sure the planter is in good working order. Inspect and adjust the planter to improve stand establishment. Operate planters at speeds that will optimize seed placement. Uneven emergence affects crop performance because late emerging plants cannot compete with larger, early emerging plants.
6.Follow appropriate seeding rate recommendations. Final plant populations of 31 -33,000 plants/A are adequate for most production environments. Final populations of 23-24,000 plants/A are usually adequate for low yield, droughty soils.
7.Supply the most economical rate of nitrogen. Recommended N rates have been updated and will be made available at the end of March. Consider side-dressing and using an application method that will minimize the potential loss of N (incorporation/injection, stabilizers under high risk applications, etc.).
8.Utilize soil testing to adjust pH and guide P and K fertilization. Avoid unnecessary P and K application. High soil tests do not require additional inputs.
9.Perform tillage operations only when necessary and under proper soil conditions. Deep tillage should only be performed when a compacted zone is detected and soil conditions are dry (usually late summer).
10.Control traffic over field. Larger field equipment means greater chances of soil compaction. Use controlled traffic (driving over same tire tracks for field operations) to compromise only a small percentage of the field, leaving the majority of the field undisturbed. Maintaining soil physical structure is a long-term management strategy for productivity.
11.Take advantage of crop rotation - corn grown after soybeans will typically yield 10-15% more than corn grown after corn.
12.Monitor fields and troubleshoot yield-limiting factors throughout the season.
These are by no means the only management practices with which growers need to be concerned but they are keys to achieving high corn yields.