Our corn silage production season is about to start. The primary factor that determines the potential to make high quality silage is harvest moisture content. If the crop is not chopped at the correct moisture content, it will not matter if all the next steps are done right, silage quality will be poor. The goal is to chop corn at a whole plant moisture content of 65-70%, or 30-35% dry matter.
Some of the other keys to quality silage production involve rapid harvesting, good packing and covering the silage to exclude oxygen. Including a silage inoculant at harvest can help reduce or prevent fermentation and/or spoilage losses. Packing to exclude oxygen is critical because good silage fermentation is dependent upon anaerobic conditions. The goal is to achieve a packing density of 15 to 16 pounds of DM/cubic foot (44-46 lbs. /cubic foot as fed). The general thumb rule for a bunker silo is that you need 800 lbs. of packing weight per ton of silage delivered per hour. For example, if you have 40000 lbs. of tractors, divide that by 800 and it tells you that you can adequately pack up to 50 tons of silage delivered to the bunker/hour. If your chopping rate is higher than that you need to get more packing weight on the pile.
As soon as the silage is packed, it must be sealed to exclude oxygen. Some University research suggests that using an oxygen barrier film product before covering with a standard silage cover plastic can help to reduce the shrink loss in the outer 2-3 feet of the corn silage pile by 40 to 50%.
More information about corn silage production is available on the Wayne County Extension web site at: http://go.osu.edu/agwayne.