Strong winds this past weekend knocked down corn in central Kentucky. Much of that corn was in the dent stage (growth stage R5) and had not reached blacklayer (growth stage R6). Those kernels will prematurely reach black layer and will be lightweight. Furthermore, these kernels will be above 35 percent grain moisture, but drydown will be hindered. Many fields across the Midwest had downed corn in July and that corn was at growth stages where it could recover, some, from the damage. Corn at R5 and R6 is too far along to recover from the damage. The only thing now is to salvage the crop for either grain or silage.
Corn kernels attached to ears that are near or on the ground will not dry down as quickly as kernels on upright plants with exposure to more air movement. Furthermore, downed ears are at greater risk for ear molds and mycotoxins. Corn for grain is still an option, but the corn will have to be harvested wet and dried in a bin. The grain moisture could be as high as 35 percent which requires a lot of drier use. Take the next several days to be certain your bins and driers are ready for use. Then, monitor your fields and harvest once they reach blacklayer.
If possible, segregate harvest loads. Up to 5 percent damaged kernels are allowed for U.S. no. 2 corn. Grain harvested from downed corn is more than likely going to be above that threshold and you do not want to penalize your grain from good fields with grain from the damaged ones. If the grain is harvested early and ear molds are not a problem, then the corn grain should be fine to feed to livestock. A test for mycotocins is an excellent idea, just to be safe. Test weight may be less and rations may need to be adjusted to the lower test weight.
Silage may be a better option for some producers, especially those who feed the corn to their livestock. If ear picking was the primary harvest method, the whole ears would need to be picked at high moistures. The high moistures will not dry very well in cribs. However, much of this corn was close to the proper growth stage for silage. Whole plant moisture should be around 65 to 70 percent for bunker silos and when the kernels are about 3/4 milk line.
Before making any harvest plans, contact crop insurance adjusters, if applicable.
For more guidelines on harvesting options for downed corn, contact your county extension office.
Sources:Abendroth. L. 2006. Corn development from R1 to R6. Iowa State Extension. http://www.agronext.iastate.edu/corn/production/management/growth/yield.html Lee, C. and J. Herbek. 2008. Ike Hammer Corn, Hinders Harvest. University of Kentucky. http://www.uky.edu/Ag/GrainCrops/Briefs/Corn_Lodged2008.htm Lee, C., J. Herbek. G. Lacefield and R. Smith. 2006. AGR-79 Producing corn for silage. Univ. of Kentucky Coop. Extension Serv. http://www.ca.uky.edu/agc/pubs/agr/agr79/agr79.pdf. Nicolai, D. and D. Hicks. 2006. Corn development and maturity as affected by wind storm damage. Minnesota Crop eNews. Sept. 1. http://www.extension.umn.edu/cropenews/2006/06MNCN53.htm