The fall of 2009 was fraught with weather-related harvest problems that hindered the storage of feedstuffs for many U. S. and Canadian producers.
While spring seems a long way off, one must realize that once the freezing temperatures are gone, spoilage could be a risk, especially for those wet feeds and silages if they did not ensile properly.
One of the problems we had last fall was related to the less-than-ideal storage conditions for corn silage. While producers had little choice but to make feed before the snow began flying, we knew at that time Mother Nature’s giant refrigerator would cool and keep our wet feeds protected from the advent of spoilage until spring. By that time, if the frozen-green-chopped forages had not gone through proper fermentation, the rate of spoilage could become a huge problem with the arrival of warmer weather.
Granted, warm days are likely far off, so now is the time to estimate your carry-over feed and adjust your rate of feed-out if spoilage is going to be a problem. The faster silage is fed off the face of a bunker or pile, the less time it’s exposed to oxygen and subject to spoilage. Forage specialists generally suggest a storage design that allows for a feed-out rate of one foot per day.
W hat a lot of people don’t
understand is that oxygen can penetrate quite a ways into a feed-out face. In some instances, the hot zone was as far back as three feet. This is important for first-time silage makers, particularly those who decided to ensile corn. This unfamiliarity could result in substantial losses this year.
Producers may not know that this zone of heating is causing dry-matter losses because it’s out of sight. The feed-out face actually might be cool to the touch because the readily available carbohydrates already decomposed days ago and it has had a chance to cool.
Brian Holmes, a University of Wisconsin agricultural engineer, notes that some feeders do realize the losses are occurring but come up with the wrong solutions.
“You’ll see where people are tunnelling down through their silage,” Holmes says. “They have come to realize that a small distance fed out each day results in always feeding spoiled feed. So they will increase their feed-out rate by tunnelling down through the silage.”
Slow feed-out rates or tunnelling to avoid the problem suggests that the storage was made too wide in the first place.
“They’re feeding out at a much higher rate because they get better feed quality while they are feeding,” Holmes says. “In the meantime, everything else that’s exposed is deteriorating in much the same way as an uncovered storage pile.”
His solution is to feed at a faster rate across the entire face of the forage. Let’s say the zone of heating is in the two-to three-foot range. If you feed out at the rate of one foot per day, the heating can happen for only up to three days before you actually get to that point and feed it out. If you’re feeding at six inches a day, you have up to six days for the decomposition to occur.
The best solution is to design bunkers and piles for a one-foot-per-day feed-out rate. That may mean adding bunker walls or building more and smaller piles. Reducing the size of the pile or bunker face ensures fast enough feed-out and that the remaining silage stays under plastic and is protected from air, Holmes says.
Granted, you are not going to build bunkers this time of the year. Nonetheless, for the future, seek bunker and pile-sizing assistance, such as the spreadsheets available from extension at http://www.extension.org/pages/Silage_Management_Considerat ions and the University of Wisconsin forage team at http://www.uwex.edu/CES/crops/teamforage/.