With the weather events of late 2018 and early 2019, many farmers found themselves planting corn much later than usual, some even into July. For those chopping their corn for silage, this can be a big concern.
There are two peaks in forage quality: pollination and 50 percent milkline. The pollination peak is generally too wet to go in the silo, so the second peak is the one we use more often. At 50 percent milkline, whole-plant dry matter content is good for chopping and ensiling (32-36 percent dry matter, 64-68 percent moisture).
So, what do you need to know as you look at getting those silage acres harvested before the first frost? Here are a few things to keep on your radar:
Forage quality doesn’t change much between April-June planted corn and July planted corn, around 5-8 percent; however, milk-per-acre levels can decrease by up to 92 percent in July planted corn.
Getting the correct moisture for fermentation can be more important than forage yield. Since the wettest part of the plant is the lower stalk, raising the cutter bar 12 inches can lead to a 3-4 percent decrease in moisture. This can improve forage quality, but decrease yield and milk per acre.
If pollination does not occur, a corn plant will have a higher sugar content, higher crude protein, higher crude fiber and higher than normal digestible fiber. However, overall yield significantly decreases.
Without pollination, green stalks will be 75-90 percent water, making them too wet to ensilage. If you do chop this corn for silage, be sure to check whole plant moisture.
If corn plants go through frost before they reach dough stage, the whole plant moisture may not drop enough for fermentation. If you’re looking at a frost before dough stage, cut the corn earlier and wilt it in the field to a more desirable dry matter content.
If frost occurs during the dough stage but before 50 percent milkline, field dry until whole-plant moisture drops to 64-68 percent. The more mature the kernel gets prior to frost, the shorter the drying period.
Sources:
https://agcrops.osu.edu/newsletter/corn-newsletter/2019-29/harvesting-late-planted-corn-silage