Harvesting corn for silage leaves little plant residue on the ground to help control water runoff and soil erosion. A cover crop either interseeded before or planted immediately after silage harvest will help protect the soil from wind and heavy rains. An established cover crop also helps improve soil structure and uptake of nutrients.
Factors to Consider
- Soil benefits
- Type of cover crop
- Planting time and method
- Terminating spring growth
- Clarify needs. Cover crops offer many benefits, but they can’t do it all. Determine priorities in your fields and focus on the top two or three you want to address with cover crops, such as soil erosion, runoff or compaction.
- Cover crop selection. A wide variety of cover crops are available, and the list expands each year. Use resources to help determine the best cover crop for your operation. Cover crops commonly used on corn silage ground include rye, ryegrass, red clover, hairy vetch, sweet clover and barley. Tillage Radish® cover crop radish seed also is growing in popularity for breaking up compacted soils. Also consider what will be planted in the field the next year. Forage grasses are recommended for when soybeans will be planted. A legume or combination crop is recommended when grain corn or corn silage hybrids will be planted.
- Planting requirements. Seed your cover crop early enough to establish a thick growth. Otherwise, it can’t do its job. Most cover crops should be in the ground by mid to late September, just after corn silage is harvested. Interseeding the cover crop into the corn allows the crop to establish before silage harvest. Most interseeding takes place at cultivation when the corn is 6 to 24 inches tall. Other planting options include seeding 10 to 14 days prior to silage harvest by aerial application or high clearance spreaders. Higher seeding rates and grass crops may be required in these scenarios.
- Terminating cereal grain cover crop. The spring regrowth that occurs on overwintering cereal grain should be terminated as late as possible to obtain full benefit of the cover crop. Glyphosate and sethoxydim herbicides are recommended for killing the spring regrowth.
Fields harvested for corn silage have little residue remaining on the ground. Cover crops either interseeded in the corn or planted immediately after harvest can reduce soil erosion and provide other benefits to improve the soil. For more information, contact your local Mycogen Seeds customer agronomist or trusted agronomic adviser.