Howard F. Schwartz, Colorado State University, Bugwood.org
The minimal amount of rain during the latter portion of the growing season has caused some concern among growers for the lack of grain production on silage corn ears, as well as the concern for corn that is too dry to chop for silage.
Last week's corn silage samples collected by Alyssa Collins, Director of the Southeast Agricultural Research & Extension Center in Landisville and Assistant Professor at Penn State, show how progressive the southern portion of Pennsylvania's corn has already dried down for differing relative maturities, which can be magnified by variability in hybrids. These samples indicate that silage harvest for most of the state - particularly the southern portion - is beginning to wind down.
|Relative Maturity||Date: 9/8/15|
|106 day, planted 5/12/15||57%|
|109 day, planted 5/13/15||53%|
|113 day, planted 5/13/15||58%|
With corn silage drying down rapidly this fall, some farmers are faced with the challenge of standing corn that has already dried past the optimal moisture for silage harvest. If harvesting dry shelled corn is not desired, different harvest options are available, including harvesting snaplage and high-moisture ear corn; however, careful management is necessary to optimize feed quality and reduce the risk of mold and mycotoxins.
Corn snaplage is a fermented feed consisting of the grain, cob, and husk of the plant. This would be a good option for operations whose goal is to utilize the cobs and husks for roughage in the ruminant diet. Optimal kernel moisture is between 28-34% (35-40% whole plant moisture) and should not be harvested for snaplage if the kernel is less than 25% moisture, which will lead to fermentation issues and ultimately affect the digestibility and palatability of the corn. The black layer is typically present at approximately 28-35% kernel moisture, indicating optimal moisture for harvesting. Snaplage is harvested by a silage chopper with a snapper head and processed by the chopper's kernel processor. More information is available through a University of Vermont factsheet.
High-moisture ear corn should be harvested when kernel moisture levels are between 26-30% or whole ear moisture reaches 30-35%. High-moisture corn is harvested using a picker or a modified combine to save parts of the cob, then ground using a tub grinder at the storage structure. The ground corn is then packed in the storage structure to eliminate air and proceeds through the fermentation process.
Snaplage and high moisture corn should be ensiled as quickly as possible after harvesting, as loads left for long periods of time or overnight will begin to spoil. Airtight storage structures are essential, as the elimination of air is crucial to proper fermentation.
When harvesting high-moisture ear corn and snaplage, farmers should recognize that careful attention needs to be paid to management, as significant spoilage losses can occur if proper ensiling techniques are not followed. While there are many benefits to harvesting drier corn for the purposes above, farmers should be aware of the disadvantages and risks involved in these types of harvested feeds. Consult the Penn State Agronomy Guide, extension factsheets, or local extension educators for more details on management.