Silage harvested this year has had time to fully ferment and producers may be in the process of feeding off of a pile. Most of us are very aware of the importance of proper management during harvest for a quality feedstuff. However, the situation can be quite different when the silo is open and fed out.
Once packed and fermentation completed untouched silage can be preserved for a long time. However, that state of long-term preservation changes as soon as we start feeding. Once the silage is exposed to oxygen, aerobic fermentation starts to take place and the material starts to deteriorate. As I heard it put recently, “A silage pile is like we raked together a big pile of leaves. We use fermentation magic to keep it stable, but when it is exposed to air, we turn our silage pile into a compost pile and it starts to decompose.” For this reason, it is recommended to minimize the silage face’s exposure to the air. Easier said than done.
As we pull silage from the pile to feed, a well packed silage reduces the ability for oxygen to penetrate from the exposed face. Removing a small amount equally across the face daily is another good practice that reduces the duration of time silage is exposed to air and can help limit mold growth and decomposition. A good rule of thumb is to remove 6 to 8 inches daily across the entire face. Minimum removal should be 4 inches daily in the summer and 3 inches in the winter.
Pile size is critical to managing removal properly. While it’s a bit too late to change things this year, next year we can estimate how much we need to feed daily and try to adjust pile proportions to better fit daily removal. The University of Wisconsin recommends using a face removal rate of 12 inches per day when planning silage piles with no more than three days of silage unprotected by cover at any one time.
While specialized silage facing tools are available, spending money on a specialized piece of machinery to maintain a smooth silage face may only make sense for operations regularly feeding large amounts of silage.
In the case where regular farm equipment is used, operator skill when removing feed becomes paramount. For instance, extracting silage from the silo pit, with a payloader results in a vastly different open face when the payloader is used going into the face from the front than when it is operated from side to side of the face “shaving” its surface. Again this is all about oxygen management. A smooth face has less surface area for oxygen to interact with and begin decomposition than a ragged one, especially if removing feed roughly opens up larger cracks deeper into the silage pile.
A final and especially important consideration is worker safety when working with the vertical face of a silage pile or pit. While they may seem stable, collapse can happen at any moment and without warning. This is particularly important when working in silo bunkers of large sizes, and heights.
How we feed silage can be just as important in maintaining quality as putting it up. In summary, remove the amount of silage that is going to be used, using the technique or gear that leaves the smoothest face and expose the smallest surface possible. Most importantly, be overly cautious when working close to the silo open face.
-Ben Beckman is a beef systems Extension Educator serving the counties of Antelope, Cedar, Knox, Madison and Pierce. He is based out of the Cedar County Extension office in Hartington. You can reach him by phone: (402) 254-6821 or email: ben.beckman@unl.edu