Sept. 11, 2015

Last week a couple farmers telephoned me, concerned that the corn they were chopping for silage was too dry.  They knew that dry silage often heats and molds, lowering its energy and protein digestibility.  This happens primarily because dry silage is difficult to pack, which allows more oxygen to remain embedded inside the silage.

Many corn fields are quickly getting too dry for making the best silage. Adding water to increase moisture content is next to impossible.  It takes about 7 gallons of water for each ton of silage to raise moisture content just one point.  Even if you have enough water, the chopped corn can't absorb it fast enough to do any good.

Your main goal must be to minimize oxygen in your silage. One solution may be to blend a wetter feed, like fresh alfalfa, forage sorghum, or green soybeans with dry corn. Another option would be to use later planted corn that's still quite green.  It can be tricky to get the right combination, but it can produce excellent silage.

Another option is to adjust knives to cut finer and add extra packing weight, even if the chopped corn seems to spring right back up at you. 

When packing, save your wettest forage for the top layer. This helps add extra packing weight and gets better sealing.  If you do have water handy, apply it to this top layer for even more packing weight.  And, of course, always cover dry silage with plastic to prevent outside air from seeping in.

To make the best silage, get the moisture right. If it's already too dry, chop extra fine, pack well, and cover with plastic for best results.

Bruce Anderson
Extension Forage Specialist