Minimizing stored forage losses
January 3, 2020
Forage losses at harvest, storage and feeding has been estimated to be as much as 20%
Forage losses at harvest, storage and feeding has been estimated to be as much as 20%. This is of course a huge inefficiency for producers and can have a large impact on farm profitability. Since forage has already been put up for the year let’s focus on things that we can do now to help reduce losses.
Forage loss is primarily in two categories: escape through handling and storage processes and microbial deterioration. Most forage losses through handling and storage can be seen as forage that is on the ground or lying around on machinery. Whereas microbial losses can be much harder to see and often times go unnoticed. Many of these types of losses are due to insufficient packing density allowing oxygen to remain in the silage, or improper coverage exposing the silage to oxygen and air. Here are some things to be thinking about when looking to prevent forage losses.
Proper maintenance of storage facilities. It is important to properly maintain walls, doors, and ceilings of silos. This should be done regularly to help minimize air exchange and exclude precipitation from entering the silo through potentials cracks in concrete and around door. An indication that your silo may need maintenance is to keep track of spoilage around doors and walls. If spoilage steadily increases from year to year it may need maintenance even if cracks are not visible.
Proper maintenance of plastic. Silo bags, bunkers, and piles all rely on plastic to exclude air and precipitation from the silage. Punctures in this plastic can happen due to a variety of causes including people, animals, and weather. These punctures will let air and water in which will cause losses. For silage bags, measures should be taken to locate these bags away from areas that increase the likelihood of punctures. Also, be cautious when operating equipment near the bag to keep from puncturing the bag. Bags should be inspected weekly and holes repaired with tape provided by the bag distributor. This tape should have low oxygen permeability.
For plastic covering bunkers and piles, the thicker the plastic used the more resistant to tears and oxygen infiltration. For this plastic to be effective it must held and sealed tightly to the silage surface. It should also be sloped appropriately to drain water away from entry points into the silage. It also must be free of tears and holes. Inspection should take place every week and repaired with oxygen excluding tape.
Proper feed removal. Removal in a manner that leaves a rough, disturbed surface will cause higher losses than those that leave a smooth, undisturbed surface. Both dry matter density and feed out rate will influence the amount of air exposure. With dry matter losses decreasing as silage density increases and/or as feeding rate increases.
Even though increased feeding out rates can reduce losses, remove only the quantity needed for the current feeding. Silage exposed to outside air for an extended period of time will deteriorate faster. It is also recommended to roll back silage covers on bunkers and piles no more than 3 days’ worth of feeding at a time. This is similar for silo bags as the feed out face should be kept as tight as possible with minimal losses left around the bag. Silo bags, bunkers, and piles should be placed on a surface that allows for feed removal without having to operate in mud. Whatever the removal practice, it needs to leave the silage feed out face tight and smooth.
Most of the above information comes from articles “Preventing Silage Storage Losses” (Holmes and Muck 2000) and the “Shrinking your Forage Shrink” by Stan Moore from Michigan State University. For more information visit the UMN Extension website or call the County Extension office in Foley 320-968-5077.