Whether forage sorghum becomes hay or silage, is used in a summer grazing program or as an alternative crop, interest in it is definitely picking up.
So say Texas A&M University’s Brent Bean, extension agronomist, and Ted McCollum, extension beef cattle specialist.
Seed dealers attending the annual Forage Sorghum Variety Trial Field Day are seeing large increases in forage sorghum sales to dairies and feedyards, Bean says.
This year's university trial at the Bush Farm, near Bushland, TX, included more than 90 entries comparing a wide variety of sorghums. They include: brown midrib, photo-period sensitive, forage sorghum, grain sorghum, sorghum/sudangrass, sudangrass and even some sweet sorghums aimed at the bioenergy market, Bean says.
Each type of sorghum has its strong points, he adds. The brown midrib varieties, on average, produce higher-quality silage, and the non-brown midrib varieties typically produce higher yield.
The photo-period sensitive varieties can produce very high yields if a one-time cutting is used, or can be harvested 60-70 days after planting for a haylage crop and then cut again 45 days later, he says. In this system, a producer can still plant wheat after second cutting.
Several varieties identified in experiment station trials produce a consistent high yield along with quality similar to corn silage, Bean says. These varieties are now being labeled with tags from the National Sorghum Producers.
The National Sorghum Producers cited changes in silage sorghum genetics and the continued research and development of high-quality forages when it launched a branding program aimed at helping producers make seed selection decisions.
In another area, producers are taking a second look at sorghum-sudangrass for their summer stocker grazing programs, McCollum says.
Studies in the first five years have shown the brown midrib sorghum sudangrass was more digestible and produced higher daily gains than the photo-period sensitive and conventional varieties tested, he says. Grazing cattle gained an average of 2.8 lbs/head/day.
The same studies, however, showed photo-period sensitive sorghum sudangrass had a greater yield potential and supported higher stocking rates, McCollum says.
In this year's grazing trial, fields were stocked with 725 lbs of cattle per acre to nearly 1,400 lbs of cattle per acre to look at individual steer gain and also gain per acre, he says.
The objective is to establish gain response curves that stocker operators can figure into their budget projections to determine the most economical grazing system, McCollum explains.
Overall, he says, no statistical difference in the gain per acre was determined, which means producers have flexibility in choosing varieties that suit their operational needs.
"What is best for producers to plant will be a function of the market and where they are going with their cattle," McCollum says. "Individual producers may have different objectives."For instance, given the price of cattle now, stocker operators that own the cattle and then market feeders may want to put more emphasis on gain per head rather than gain per acre," he said. "While producers that retain ownership through the feedlot may have different priorities."