Kevin Spurlin is the author of this article. It originally appeared on Virginia Cooperative Extension. Click Here to view Kevin's post.
High feed prices motivate dairymen to evaluate every aspect of their nutrition program including their home grown forages. Forages are typically the cornerstone of a dairy’s feeding system with corn silage as the standard by which most other forages are measured due to its consistency in combining high yield and high quality. Other common forages offer niches when compared to corn silage such as alfalfa’s superior protein content or agronomic advantages of winter small grains in cropping rotations. So where does brown midrib (BMR) brachytic forage sorghum fit in?
A warm season annual like corn, BMR brachytic forage sorghum grows in much the same seasonal window. It is more efficient than corn in water and nitrogen use, requiring less of both. Dr. Chris Teutsch of the Southern Piedmont AREC showed establishment cost for forage sorghum was almost $40/acre less for seed and $50/ acre less for fertilizer compared to corn. Additionally, it is more drought and heat tolerant than corn. Like traditional sorghums, these new varieties possess many of the same attributes including the possibility of nitrate and prussic acid poisoning, but these issues are manageable.
What makes these new BMR brachytic varieties unique? First, the BMR trait results in lower lignin content, which increases forage digestibility. Second, brachytic refers to the dwarfing trait resulting in less stalk and more leaf area. Combining greater leaf:stem ratio with less plant lignin, and adding the seedhead at harvest results in forage quality that compares quite well with corn. Dr. Teutsch observed DM digestibility of BMR forage sorghum at 74%. Data on nutritional quality is still limited, and may vary by variety.
Given BMR forage sorghum’s attractive quality traits, establishment costs, and its ability to handle hotter, drier and slightly more acidic growing conditions, these newer varieties offer two distinct opportunities for consideration in your forage program.