|Patz Model 98C Surface Drive Silo Unloaders
help keep silage compacted for better quality feed!
A good packing density (min. 15 lbs. DM/cu. ft.) is essential for preserving silage quality, preventing spoilage, and minimizing dry matter losses. Various factors influence packing density, a number of which can be controlled through proper management.
Bob Charley identified 8 such factors:
- Forage maturity/dry matter
• Wetter forage: Compacts more easily. Seepage and a butyric fermentation more likely.
• Drier forage: Harder to pack & keep compacted. Higher levels of yeasts and molds more likely.
- Chop length & processing
• Easier to compact smaller particles; however, particle size must be balanced against feeding objectives.
- Storage structure
• Towers: Gravity compacts lower layers of material; upper layers not adequately packed.
• Proper management of bagging machines is critical.
- Forage delivery rate
• Control is often impractical.
• Match against optimum packing time/number of tractors.
- Packing tractor weight
• Est. amount of packing weight required: multiply est. tons of crops delivered to silo/hr. by 800
- Adding packing tractors
• Optimal packing time is 1-3 min./ton of forage.
• May need additional packing tractors to avoid impacting forage delivery rate.
- Packing layer depth
• Thinner is better – 6″ maximum.
- Silo height
• Greater height increases silage density in lower layers.
• Piles & bunkers – Greater height can result in inadequately packed upper layers which can cause safety issues while filling and at feedout!
Visit the University of Wisconsin’s website and click on
“Determining Value of Improved Silage Management” for a helpful planning tool!
Progressive Forage Grower, Issue 5, June 1, 2011.