The lack of starch in corn silage throughout the Midwest this year may provide a significant obstacle to producers trying to keep purchased costs to a minimum.

 Consider this scenario: If a dairy producer had a high corn silage lactating diet, and switched from last year’s average corn silage (36 percent starch) to this year’s (27 percent starch), it would cost over 30 cents per head per day to purchase the corn needed to supplement the ration.

From a laboratory perspective, it’s unusual to see a trend in forage quality spread over such a large area due to the variety of soil types and agronomic practices. However, this year appears to be an exception with no state in the Midwest averaging more than 28 percent starch in fresh whole plant corn samples. In fact, the states of Missouri, Kansas, Nebraska, and South Dakota each averaged less than 20 percent starch.

In addition to the lower average starch content, the Midwest is showing unprecedented variation in quality of the corn silage crop. In most years, the standard deviation for starch content is 5 to 6 percent. This year, the standard deviation for the midwestern states is 11 to 13 percent.

Variation in corn silage quality across farms will be unusually high, and it seems reasonable to conclude that tracking variation within farms will be more important this year than most.