Chopping Corn for Silage

Dry conditions are still affecting forage production throughout the state of South Dakota. Dealing with drought conditions when feeding dairy and beef cattle can bring serious challenges to production including a short or unavailable hay supply in Western areas of the state.

Beginning this week, we are going to see corn being chopped for silage. Here are some tips and guidelines that will help producers get the best out of this crop. Corn for silage should be harvested between 60-70% moisture, which is ideal for optimum fermentation and a rapid drop in pH to preserve the feed value of the crop.

Harvest Tips: Getting the most out of your corn silage

• Keep a close eye on corn maturity once it has dented. Corn can rapidly mature or dry down due to the weather and moisture conditions. This year is not the exception as we are facing considerable dry conditions.
• The kernel milk line is the best estimate of whole plant moisture for harvest. The kernel milk line is the dividing line between sugars in the maturing kernel and starch. In South Dakota most producers will use the 1/3 milk line as a benchmark to start checking whole plant moisture and decide whether it’s the right time to harvest. If a producer harvests corn silage at 30% dry matter (DM), this will result in lower starch concentration in the silage. Mature corn silage with more than 30% DM could also imply less nutritional value because of lower fiber and starch digestibility.
• If corn to harvest is still immature, allow the crop to mature to increase DM yield per acre.
• Adding a research-proven bacterial inoculant to corn silage can reduce dry matter losses and increase digestibility.

Determining chopped silage moisture content with the squeeze test method

Squeeze some chopped forage in your hand, if the silage…

• Holds its shape and there is considerable free juice dripping the moisture content is over 75%.
• Holds its shape but there is very little free juice dripping the moisture content is 70-75%
• Loses its shape and there is no free juice dripping the moisture content is 60-70%
• Rapidly loses its shape the moisture content is below 60%

Source: Karla Hernandez, South Dakota State University