Nature

Hybrid Bermudagrass

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It’s difficult to imagine the Southeast before fescue and hybrid Bermudagrass, but a few farmers and researchers, too, remember it very well. They paint a desolate winter landscape of the South in the ’30s, fraught with deep roadside gulleys, eroding pastures, and guant, spindly cattle.

The area’s few native grasses – indiangrass, big bluestem and switchgrass – all but disappeared with the native Americans. These species, well-adapted to drought and acid soils, but not to the abuses of hungry cattle, were overgrazed by imported European livestock.

In their place grew broomsedge and a few other native species that could survive in the leached, infertile soils. Of little nutritional value, these grasses could not support many livestock, much less an industry. So for many years agriculture in the South centered almost entirely on row crops and cash crops such as cotton.

If not for travelers from faraway lands, this might still be true. Nearly every forage important to the South – and indeed much of the U.S. – came from elsewhere: Common Bermudagrass from Africa; Dallisgrass from Argentina and Brazil; Johnsongrass from the Mediterranean; and from Brazil, bahiagrass. Tall fescue, the most widely grown pasture grass in the country, came from Europe, probably mixed with other grass seed.

While these imports improved forage production, it wasn’t until the 1940s, when agricultural researchers began breeding for improved nutrition and yields, that livestock production became significant in the South.

The first milestone came with the release of Coastal Bermuda, a hybrid Bermudagrass developed by U.S. Department of Agriculture plant breeder Glenn Burton at the Coastal Plain Experiment Station in Tifton, Ga. Cattle gains rose from an average 60 pounds a head per year on well-managed native grass pastures to 275 pounds per head in a year on Coastal Bermuda. It was drought- and frost-tolerant, high yielding and nutritious.

“Glenn Burton’s work with Bermudagrass marked the beginning of the use of perennial grasses,” says forage breeder Joe Bouton. “It was an important milestone in the move toward stable cattle production.” Coastal Bermuda formed a forage base for cattle production in the Coastal Plain and provided warm-season grazing in northern areas in the Southeast as well. It remains an important variety today, though Burton has released a long list of other high-yielding forges and turfgrasses, too, in the 50 years since.

In 1943, with the release of Kentucky 31 Tall Fescue, livestock producers in northern regions of the South gained a forage staple as well. Originally introduced to fight erosion, tall fescue, which is easily established from seed, soon became the forage of choice in much of the country, including the upper South. In the 1970s, USDA researchers discovered an endophytic fungi in tall fescue that helped the grass survive the stress of drought, insect pests and disease. This endophyte can also make cattle sick. Cattle grazing on infected fescue pastures often seek shade and water, have a rough hair coat and lose weight.

Researchers countered by developing varieties without the endophyte, but these grasses aren’t as tough. So plant breeders are back at the drawing board, breeding for varities that contain only small amounts of an ergot alkaloid, the substance in endophyte that causes problems for cattle. Other reasearchers at the Coastal Plain Experiment Station are developing a vaccine to protect cattle grazing endophyte-infected fescue pastures.

The vast majority of permanent pastues in areas such as south Georgia today consist of Bermudagrass and/or bahiagrass. In the upper South, pastures usually include a combination of Bermudagrass and tall fescue. The pastures are tough, drought-tolerant and reliable, and many livestock farmers do little more than apply a little lime and fertilizer each spring.

But researchers believe most producers in the South could be far more productive by becoming grass farmers rather than livestock farmers. This means growing and managing high-quality forages, including legumes and even alfalfa, to improve animal nutrition. Scientists are focusing on ways to help livestock producers improve and upgrade existing pastures.

Bouton and forage researcher, Carl Hoveland, have for the past decade looked at the best legumes and management strategies to boost forage quality. They conduct many of their studies at the Central Branch Experiment Station in Eatonton, Ga., which straddles the geographic boundary between the Piedmont and Coastal Plain.

“In the past decade, we’ve looked more at upgrading with legumes, to fill in the seasonal gap,” says Bouton. “Each of these grasses has an ‘off’ season where producers have traditionally fed hay – and hay that’s often very low in nutritional value.”

The scientists have experimened with red, white and ladino clovers, sericea lespedeza, annual ryegrass and birdsfoot trefoil. They plan to look at perennial peanut, a low-growing legume that’s gaining favor as a forage in south Georgia. Hoveland and Bouton work mostly with animal scientist Mark McCann in assessing both animal performance and producer accpetance of new forage varities and alternative management practices. “The goal,” says McCann, “is to help producers get the best return on their investment, and that means improving forage quality.”

Two years ago, Bouton released Alfagraze, the first grazing-tolerant alfalfa for the South. It’s been very well received, especially among dairy farmers. Several years ago, he released Georgia 5, the first tall fescue designed especially for south Georgia producers. “Dependability is the key,” Hoveland says. “Farmers want forages that are tough and reliable under all conditions. We’ve probably concentrated too much in the past on high yields and not enough on varieties that are consistently dependable. But that’s changing.”