In the more humid regions, there’s no question that the use of forage sorghum, sorghum-sudangrass, sudangrass, and pearl millet has become more popular as a warm-season annual forage resource.
Last year, with a lot of unplanted or late-planted acres, more than the usual amount of sorghum species were planted and harvested. It was also a year where sorghums didn’t perform up to expectations in many cases because persistent cool, wet weather conditions.
In the same way that our cool-season annual and perennial forages don’t perform to peak levels under dry, hot conditions, warm-season sorghums are not well adapted to cool temperatures. However, they can offer exceptional performance and forage yields under normal summer conditions. This variation in performance has left our world full of sorghum lovers and haters and opinions ranging from undependable to forage savior.
Jeff Jackson is the national forage sorghum product manager for Croplan by Winfield United. When selecting seed genetics and feeding for dairy or beef performance, Jackson recommends that growers look to the more highly digestible brown midrib (BMR) options. “It may cost a little more, but you’ll easily make that up with more milk or animal gain, palatability, and less feed waste.
“You can’t rush the planting date,” Jackson said. “You need consistent soil temperatures above 60°F at 8 a.m. before you should think about planting. If you don’t heed this rule, germination and seedling vigor will be compromised. Patience is a virtue with sorghum planting. If planting pearl millet, hold off until morning soil temperatures are 65°F or above,” he added. These temperatures are well after the last frost.
Jackson explained that the recommended seeding rates have changed as new genetics have entered the market. “Genetics have improved for fiber digestibility, which allows us to plant less seed per acre while improving standability and producing excellent yields.” Sorghum-sudangrass hybrids can be successfully established at a seeding rate of 15-25 lbs/A. “The optimum rate will vary with local rainfall patterns, soil types, and planting methods.” (Note: in Kentucky we still recommend 20 to 25 lbs/A when drilling and 25-30 lbs/A when broadcasting.)
“It’s a myth to think that you shouldn’t fertilize to avoid high nitrates,” Jackson said. “Proper fertility is actually needed to reduce nitrate potential. I tell growers to apply nitrogen and sulfur at a 5-to-1 ratio, having 1 to 1.2 pounds of nitrogen per day of growth is the standard.” And summer annuals are like alfalfa and remove high amount of potash. Make sure to soil test to determine proper fertilizer rates.
If using a multi-cut crop such as sorghum-sudangrass, Jackson recommends split-applying nitrogen; this helps to prevent luxury consumption of nitrogen and high nitrates in first cutting. Forage sorghum, sorghum-sudangrass, or sudangrass are receiving more interest and use than ever before in the humid regions of the U.S. They offer a lot of value in both grazing and conventional-harvest systems. ~ Mike Rankin, excerpt from Hay and Forage Grower. Read the full article here.