Forgotten Hybrid Fills Forage Gap

A hybrid plant that languished for decades as a disappointing grain crop could find new life as forage to fill an early-summer grazing gap from Kansas to Texas.

The forage, agrotricum, was developed in the 1930's by California plant breeders dreaming of a perennial wheat.

A cross between the annual common wheat and a perennial wheatgrass, Agropyron spp., agrotricum didn't live up to the breeders’ hopes.

But recent field tests at El Reno, Oklahoma, have shown that a strain of agrotricum can provide up to 6 weeks' more cool-season grazing for cattle than the winter wheat widely grazed on the Southern Plains.

"Nearly all the Agropyrons are perennials, but that first cross didn't produce a perennial," explains Jerry D. Volesky, an Agricultural Research Service animal scientist in the agency's Grazinglands Research Unit at El Reno. "And while the kernels looked a lot like wheat kernels, they had poor milling and flour qualities."

Researchers at Oklahoma Stale University obtained agrotricum seeds about 25 years ago when searching for disease resistance characteristics that could be bred into Oklahoma wheat. The OSU researchers crossed agrotricum with still another wheat to produce OK906 agrotricum, which is an annual plant. ARS scientists from El Reno saw a test plot of OK906 at Stillwater, Oklahoma, and, impressed by its continuing growth in early June, took seeds back to El Reno for field trials.

Now in its third year of testing, OK906 agrotricum offers good-quality grazing from mid-November to late spring, Volesky says. It will be jointly released by ARS and OSU, and seed should be available to farmers in mid-1995.

"OK906 is comparable to wheat as far as forage quality and protein levels," he points out. "But it also offers good pasture well into June. That's very important, because many warm-season grasses in this area aren't usually ready for grazing until June, while winter wheat grazing is mostly gone by early to mid-May. In addition, spring growth and regrowth after grazing are better for agrotricum, compared to wheat."

In the 1991-92 field trials at El Reno, agrotricum provided 226 days of grazing, compared with winter wheat’s 170 days. In 1992-93, crossbred steers were able to graze agrotricum for 182 days, but only 156 days on winter wheat.

Pounds of beef produced per acre averaged 408 on winter wheat in 1991-92, compared with 384 on agrotricum. But in 1992-93, agrotricum outpaced the wheat, with 444 pounds of gain per acre to wheat's 353. Preliminary data from the 1993-94 trials are indicating that agrotricum will produce about 100 more pounds of gain per acre than wheat.

"The fall of 1992 was very wet, so we didn't get the cattle in there until right before Christmas," notes Volesky. "One thing that contributed to the difference in the second year was that in May, the average daily gain on agrotricum was about 2.7 pounds per animal, versus 1.4 pounds for wheat. It's really toward the end of spring when you see the differences."

Volesky says agrotricum is handled and planted like wheat, with the same seeding rates and much the same fertilization requirements. In the most recent round of field trials, agrotricum was planted on September 7, 1993, and was ready for grazing in mid-November.

"Agrotricum should be a good forage anywhere wheat pasture is commonly used for grazing," Volesky concludes. — By Sandy Miller Hays, ARS.

USDA-ARS Grazinglands Research Laboratory, P.O. Box 1199, El Reno, OK 73036; phone (405) 262-5291

"Forgotten Hybrid Fills Forage Gap" was published in the January 1995 issue of Agricultural Research magazine.