Grain quality issues -- like the "blue eye" mold that began showing up in some bins last month -- have made things tough on some farmers as they try to move last year's crop out of storage to free up room for this year's corn.

Blue eye, according to Iowa State University Extension plant pathologist Alison Robertson, isn't the most harmful mold (it doesn't spawn mycotoxins of any kind and has a relatively small effect on feed value), but it can accelerate grain spoilage under the right conditions. And, those conditions have been present in many storage setups around corn country in the last 2 months.

Corn kernels show symptoms of blue eye mold. (photo courtesy Don White, University of Illinois).

"...Blue-eye mold [appeared] almost overnight in many cases in late July and early August. Once the shelf life is gone and the grain is warm and in equilibrium with about 65% relative humidity or greater, blue eye can become a problem," Robertson says. "At 80 degrees [Fahrenheit], this is about 13.5% moisture -- even dry corn can spoil in these conditions."

In the absence of mycotoxins, blue-eye mold alone doesn't deteriorate quality. But, among other factors gutting stored corn quality, it can be the straw that breaks the camel's back when it comes to being able to deliver last year's grain without fresh 2010 corn.

"At this time, the grain market has so much damaged corn in channels that few buyers are able to absorb more until the new crop arrives," Robertson adds.