How to salvage yield when early frost hits.
Agronomy Bulletin 48 ─ Drying Immature Corn
Early frost at harvest can lead to high or uneven moisture, low test weights and increased foreign material. Careful planning and management of drying and storage can help maintain yield.
Factors to Consider
- Developmental stage
- Storage options
- Test moisture levels. Uneven grain moisture levels are likely after an early frost, so check every load coming in from the field. Drying levels should be 15 percent for short-term storage, 14 percent for storage until spring and 13 percent for long-term storage. If moisture levels are extremely high, growers with livestock should consider using a portion of their acres for silage or high-moisture corn.
- Determine stage of development. Corn frozen in the milk stage will have low yield potential, so the best option for handling may be green chopping or ensiling. If corn is in the dough stage when frozen, yields and test weights will be low but moisture levels will be very high. Though field drydown can require four to nine days, the ears will eventually reach an acceptable moisture level. Immature corn frozen in both the dough and dent stage can be dried artificially using low to medium temperatures.
- Consider drying options. Natural field drying is the best way to preserve and increase test weights. Leave corn in the field as long as losses from lodging are not a threat. If artificially drying, keep temperatures low because high temperatures will increase test-weight losses and kernel damage. Remember that immature corn will require longer drying time. Increased drying cost also will be associated with frost-damaged corn.
- Ensure proper storage. Adequately cool and aerate grain after drying. Temperatures in the range of 20 to 30 F will minimize storage problems. Check bins frequently to detect potential problems early.
Early frost at harvest can result in lower-quality grain that may not store as well. Careful management is needed to dry corn properly to maintain as much quality as possible. Consult your Mycogen Seeds agronomist or other trusted resources as questions arise.