Forage sorghum will take acreage away from silage corn in dry climates facing irrigation water shortages, predict two Southern High Plains Extension agronomists.

Under full irrigation, silage corn typically produces higher yields, but forage sorghum performs better in less-than-optimal conditions, say Brent Bean, Texas A&M University, and Mark Marsalis, New Mexico State University.

Marsalis discussed the pros and cons of forage sorghum at last fall’s Western Alfalfa & Forage Conference in Las Vegas, NV, and Bean will compare the two crops during the High Plains Dairy Conference, March 7-8 in Amarillo, TX. They co-authored the paper that Bean will present.

According to them:

● Corn seed typically costs about $95/acre compared to $15/acre for sorghum seed.

● Full-production corn silage requires 20-25” of irrigation water compared to 14-18” for sorghum silage.

● Fully irrigated silage corn typically yields 27-32 tons per acre compared to sorghum silage at 20-26 tons.

● Corn silage usually has better feed value than sorghum silage, but the quality of some sorghum hybrids is equal to that of corn silage.

● Sorghum is better-able to withstand periods of drought than corn.

During his Las Vegas presentation, Marsalis pointed out that, despite outyielding corn in limited-water situations, the acceptance of forage sorghum has been low.

“The perception that all sorghums are low in nutritive value and that they are more difficult to manage than corn are two of the main arguments against them given by producers and feeders,” said Marsalis.

However, breeders have improved sorghums to the point where the forage quality of many varieties is at least equal to that of corn. In addition, brown midrib varieties are almost as digestible as corn, although most don’t yield as well as corn or conventional sorghum, he said.

“In short, sorghum type and variety selection have only added to the perceived complexity of forage sorghum production that has deterred many producers,” said Marsalis. But, “with more research information and long-term trends being defined, benefits of forage sorghum in limited-input systems will become more evident and potential acceptance increased.”