The moisture content of corn silage at harvesting time could have a profound impact on a farm’s feeding success for the entire following year. Harvesting silage too early (high moisture content) or too late (low moisture content) can affect forage yield, silage fermentation and feed quality.

John Peters, director of the University of Wisconsin Marshfield Soil and Forage Analysis Laboratory, encourages growers to periodically check actual, whole plant moisture of corn plants from various locations in the farming operation, to provide accurate input on corn silage harvest decisions. 

Producers looking for a fast turn-around in corn silage moisture results have attempted many methods of on-farm testing, including drying samples using a microwave oven, traditional baking oven, forced-air drying unit and near-infrared (NIR) instrumentation. However, Peters cites a study performed at the Marshfield lab that showed all four methods produced unreliable results that left unacceptably high and/or inconsistent levels of residual moisture.

Peters’ recommendation in a question-and-answer document on the subject is to submit samples to a reputable laboratory for dry-matter analysis. He says the minimal amount of additional time for securing results will pay off in reduced sample-to-sample variation, and more accurate decision making.