Historically high rainfall late and above average temperatures this growing season have raised concerns about crop quality and post-harvest storage. Nearly three-quarters of Iowa's weather stations reported at least four inches of rainfall or greater in September, according to the Iowa State University Mesonet data.

Iowa State University Extension & Outreach published an article addressing the grain quality concerns that are arising as fields begin to dry out.

The article highlighted ear rot as a major concern for corn. Ear rot reduces the quality of the grain and in some instances could produce mycotoxins, which are hazardous to animals and humans. Mycotoxin-contaminated grain must be segregated from non-contaminated grain and cannot be blended into "clean grain". This year's corn crop is also likely to have higher than usual moisture content, which can contribute to development and spread of molds in storage.

The wet weather also can affect soybean quality including purple seed stain, bean pod splitting and seed sprouting. Compromised or sprouting soybeans are more susceptible to fungal growth. Split or sprouting soybeans may also release free sugars and fatty acids, leading to rapid spoilage in storage. Damaged soybeans tend to have lower test weight or damaged seed coats.

Iowa State University suggests commercial elevators, feed mills, and ethanol plants consider implementing the practice of taking a composite sample for each ½ day of samples containing all loads received during that ½ day timeframe. Composite samples help to monitor, segregate, and contain toxin contamination.

The full article about the weather effects on grain quality as well as information on handling and storage is available online:

Grain Quality Concerns with Recent Wet Weather