The folks at Pioneer Hi-Bred want producers to plan ahead to achieve high-quality forage for best livestock performance. They say selecting the right time to harvest corn silage is critical and diligently monitoring moisture content is key.
Bill Seglar, Pioneer nutritional sciences veterinarian, recommends to start walking fields and assess kernel milkline levels about four weeks after silking. Milkline levels provide a quick way to visually inspect the plant's maturity. Then when corn shows some dent it's time to find samples to achieve ideal dry matter at harvest. Harvest is typically six to 10 days away when the crop is about 3 to 5% wetter than optimal.
To check milkline, using the outer half of a broke ear, remove a kernel. Either bite into the tip of the kernel or poke a knife blade or pin into the bottom and push upward until the point meets resistance. The milkline is the area from the point of resistance to the crown. One-third milkline represents 68 to 72% moisture while two-thirds milkline represents 63 to 68% moisture.