The tannin content decreases as the grain matures, and by the time grain moisture content reaches 16 to 18 percent, tannin content is low enough the grain can be fed. Brown-seeded grain sorghums are more resistant to weathering than other grain types. The seeds have high dormancy, which keeps the head from sprouting when adverse weather occurs after grain is mature. This dormancy lasts for several months. Some seeds shattered in harvesting will survive the winter and germinate in the spring, creating a weed problem in the following crop.
Tannins make bird-resistant sorghums undesirable as a feed or forage crop.
Unless you have a specific market for this grain type, don't plant it. Most varieties are of this type. They are classified as yellow in the market, and the producer is not docked as he might be for brown-seeded grain. However, you can let them field dry to 12 to 14 percent moisture content. Some bird damage and weather damage may occur.