By Scout Nelson
Warm, wet conditions this summer have increased southern rust across the region, raising concerns for corn silage. Experts explain that while southern rust does not produce toxins, it weakens plants and creates opportunities for stalk and ear rots such as Fusarium and Gibberella. These rots may produce harmful mycotoxins that can reduce feed safety.
Another issue is rapid dry down. The ruptured leaf surface caused by southern rust accelerates water loss, making plants dry faster. Silage harvested too dry can pack poorly, reducing fermentation, stability, and overall quality.
Research shows that southern rust pressure can increase fiber and drop digestibility by more than 10 percent, leaving less energy available for livestock even when yield appears normal. Testing silage at harvest and again at feed out is recommended to measure feed value and detect possible mycotoxins.
Testing hay quality is equally important for profitable livestock feeding. Knowing the protein and energy levels helps determine the need for supplements. Group hay by type, cutting, field, and weather conditions before sampling.
Use a hay probe that cores 12 to 18 inches into at least a dozen bales from each group. Send combined samples to a certified lab for analysis of crude protein, energy, and possible nitrates.
Reports from eastern and south-central Nebraska show significant fall armyworm damage to fields and pastures. These caterpillars have an inverted “Y” on the head and four spots forming a square on the last abdominal segment. Scout in the early morning or late afternoon when they are most active. Treatment is recommended when three or more caterpillars per square foot are found. Several insecticides such as Mustang Maxx, Intrepid, and Prevathon are labeled for control, but always check grazing restrictions and post-harvest intervals.
Cooler weather will eventually reduce fall armyworm activity, but close monitoring of pastures and newly seeded fields remains essential. Careful scouting, timely testing, and appropriate treatments will help protect forage and pasture quality throughout the season.
Photo Credit: gettyimages-pamwalker68
Categories: Nebraska, Crops, Hay & Forage, Weather