2024 Harvest Strategy Thoughts – Corn for Silage

Executive Summary

Agronomists and Plant Pathologists are observing increased foliar disease pressure late in the season
Proactively scout fields for foliar disease heading into your anticipated silage harvest
window
- Cool, wet weather will accelerate movement of foliar diseases higher in the
  canopy and at higher levels of severity

Avoid accelerated field dry-down due to foliar disease, and shortened harvest
window
Target 65% whole-plant moisture in silage for most storage systems
- If foliar disease is moving in quickly, begin harvest sooner than your farm might have otherwise and to optimize whole-plant moisture in silage
- If whole-plant moisture drops below 55%, consider alternatives to putting this feed in with the main silage
Practice best silage management practices, including:
- Avoid chopping overly dry and excessively diseased corn and reconsider packing this material in with the main silage
- Use a research-backed inoculant or preservative
  - Consider technologies that reduce yeast and mold growth potential at feed-out, especially if foliar disease presence increases near harvest
- Achieve excellent pack density
  - Ensure 800 to 1000 lbs tractor weight are on the pile per ton delivered per hour
- Keep air out with strong and oxygen-limiting plastic, adequate tire coverage and sealing ends or edges of bags, piles and bunkers

The WI corn crop is in a generally good condition
- Early, on-time planted corn in the best position
- Watch late-planted corn closely, which will be more impacted by late-season disease increases
Agronomists and plant pathologists are beginning to see increasing foliar disease pressure in some areas – Southern Rust, Gray Leaf Spot, Northern Corn Leaf Blight and to some extent Tar Spot
- Smith strongly encourages agronomists and producers to closely monitor for foliar disease, recognizing disease can come on strongly and quickly with cool and wet weather
We expect foliar disease pressure to be different depending upon the region, farm, and hybrid grown; and will likely not be a widespread phenomenon
- Fungicide application, hybrid disease resistance, planting time, and local growing conditions all influence disease severity
- Regional differences exist within WI, for example: Southern & Central WI seem to be experiencing greater pressure whereas E WI is lesser

Foliar disease coming on late season may not affect grain yield, however can affect silage quality through rapid dry-down in the fields and shortened harvest window
Foliar disease can quickly reduce plant moisture and nutritional quality, negatively affecting ensiling potential
- Diseased and drier whole-plant chopped corn is tougher to ferment for numerous reasons
- Sub-optimal fermentation causes secondary issues such as: poor aerobic stability, yeast and mold growth, reduced feed-out quality, and the potential for increased mycotoxin concentrations
Foliar disease will not equate to mycotoxin contamination, however the Gibberella ear rot fungus is a known mycotoxin-producing organism, and if given enough oxygen in the bunker, can continue to produce mycotoxins after packing
Silage management practices are increasingly important this year, to protect yield, preserve quality, and reduce secondary issues such as mold and mycotoxins in the bunker