Photo by Kiersten Wise

Unusually hot and wet weather this summer has raised concerns about corn silage quality. Two major issues include wrapped tassels and southern rust.

Wrapped tassels have been widely reported in the Midwest this year. They occur when tassels emerge before the flag leaf unfurls. This condition is triggered by heat, moisture and nutrient conditions. While not expected to affect yield significantly, wrapped tassels may cause poor pollination. This could lower starch content in silage, a critical component for livestock feed.

Southern rust poses greater risks. Though the disease itself is non-toxic, it weakens plants, which can lead to stalk rots such as Fusarium and Gibberella. These stalk rots produce harmful mycotoxins.

Southern rust can also accelerate dry down. This complicates fermentation, resulting in reduced yield by limiting grain fill and lower nutritive value by increasing fiber and reducing digestibility.

Additionally, wet conditions have fueled ear rots such as Gibberella, Fusarium, and Diplodia. These are all capable of producing dangerous mycotoxins. Producers are advised to test silage for feed safety through diagnostic resources, such as those offered by Iowa State University.

Read more about monitoring silage quality here.