Agronomist Says Perennial Cool
Season Grasses Have Potential

DALLAS — When producers think of winter forage, generally the first to come to mind is wheat, or perhaps rye or oats. All are proven success stories.

The problem with these annual forages relates to the expense involved in maintaining them on an annual basis. The cost of owning and maintaining equipment, the lost opportunity of fields kept fallow during the summer months, the cost of seed, planting and other incidentals, all make annuals an extremely expensive winter feeding program, says Dr. Larry Redmon.

An Extension forage specialist in the Department of Plant and Soil Sciences at Oklahoma State University, Redmon spoke at the recent Cattlemen’s College here, conducted in conjunction with the annual meeting of the Texas and Southwestern Cattle Raisers Association. Redmon offered listeners a possible winter forage alternative: cool season perennial grass species.

"Cool season perennial forage grasses offer all the benefits of cool-season annual forages without the additional costs associated with annual establishment," Redmon told listeners.

An extra benefit is that cool season perennials generally provide increased forage production over and above cool season annuals because they provide forage earlier in the season as well as later in the season.

He warned, however, that cool season perennial grasses under current evaluation are primarily introduced forages and thus require careful attention to grazing management and soil fertility.

Selecting the appropriate species for a given area is critical.

"If the species is not adapted to a particular region of the state or to type of soil, producers will experience less than satisfactory results, ranging from thin stands and low yields to outright crop failure."

He recommended that producers obtain a copy of the soil survey for their county. The survey will indicate the soil type and will also likely suggest which cool season species are best adapted to that particular area.

In his presentation, Redmon focused on species best adapted to North Texas and the Texas Panhandle. Research conducted at Oklahoma State University indicates that the tall and pubescent wheatgrass species (Luna, Manska, Oaha and Jose) are best adapted to the drier regions of the Southern Great Plains. Minimum precipitation requirements are 20 inches of annual rainfall, he said. These species have been planted on soils ranging from clay-loam to sandy, but Redmon said deep sand is recommended.

Orchardgrass, which requires deeper soils and more moisture, is best suited only for extreme North Texas. Paiute orchardgrass has been selected for improved heat and drouth tolerance and is reported to be fairly long-lived.

Bromegrass falls in between the wheatgrasses and orchardgrass in terms of adaptation.

Redmon told listeners that wheatgrass species grow successfully on moderately acid to near natural soils. Jose tall wheatgrass is recommended for more acidic sites, and is proven to grow on sites with soil pH levels as high as 10.0.

Jose wheatgrass and tall fescue grow well on sites with high water tables or that experience periodic flooding.

Matua prairiegrass has received a great deal of publicity, but Redmon warned that though the perennial exhibits impressive production the first year, it is actually a weak perennial in the Southern Great Plains and should be managed as a reseeded annual if stand persistence is to be maximized.

Improper timing of establishment, Redmon told listeners, is the number one cause of crop failure.

"There is usually a short window of opportunity for successful stand establishment. If planted too early (mid-summer), there is the possibility of seedling mortality due to heat and drouth. If planted too late, one runs the risk of seedling mortality associated with a freeze."

Historical rainfall patterns for these areas of Texas indicate that the best time for cool-season perennial grass establishment is late August or early September. The speaker recommended that producers be prepared well in advance of this desirable planting period. The seedbed should be properly prepared with the necessary fertilizers already incorporated. Seed and equipment should be on hand or at least readily accessible.

Prior to planting, Redmon recommended that soil be analyzed for nutrient content. Fertilizer and lime should be applied according to the soil analysis. If used, anhydrous ammonia should be applied prior to planting. If a dry form of nitrogen is used, Redmon said that it may be best to wait until the plants have germinated before applying the nitrogen fertilizer.

Nitrogen application rates, he noted, vary depending on precipitation and soil type. To match the production curves of most cool season perennial grasses, Redmon recommended that one-third of the nitrogen be applied in September and the remainder in late February or early March.

A useful rule of thumb to follow in determining application rates is three pounds of actual nitrogen per inch of annual precipitation for areas receiving more than 30 percent rainfall and 2.5 pounds per inch for areas receiving 24 to 30 inches of rain. Typical application rates would be 25 to 40 pounds of actual nitrogen per acre in September and 50 to 80 pounds in March. In areas that receive less than 24 inches of precipitation, Redmon said nitrogen application rates will rarely exceed 40 to 50 pounds annually.

One of the most important aspects of proper planting procedures is to start with a fine and firm seedbed, "or as some producers describe it, an alfalfa seedbed." The objective of a good seedbed, Redmon told listeners, is to maximize seed-soil contact.

Purchasing the best possible seed is also critical to overall success.

"The price of seed is a very small portion of the overall cost of establishment, but good seed can pay big dividends in germination and seedling vigor," the forage specialist said. He recommended following the published seeding rate or a slightly higher rate if quicker coverage is desired.

The seed should be planted at a depth of approximately one-quarter to one-half inch. Specialized equipment is not necessary for planting cool-season grasses with the exception of bromegrass. Most producers have had good results using their existing grain drills, though some trial and error might be needed to calibrate the drill properly. Some producers mix their grass seed with the fertilizer and broadcast it when applying the fertilizer. Others have used air seeding. Redmon stressed that if either broadcast method is used, producers should use a seeding rate that is 25 percent higher than the rate recommended when planting the seed with a grain drill.

Once established, Redmon said, proper early management can mean the difference between a vigorous and a weak stand. Grazing should be delayed until the plants have a well-developed root system. A good rule of thumb is to allow seedlings to reach six to eight inches in height prior to turning livestock in on newly established pastures. To ensure a healthy, long-lived stand, proper grazing management is critical.

"Maximum net returns from livestock production systems do not occur at maximum stocking rates," Redmon reminded listeners. "Using a moderate stocking rate for cool-season perennial grasses will help ensure stand longevity, reduce the potential for weed infestation, maintain the carrying capacity of the management unit, and maximize the profitability of the enterprise."

The amount of grazing pressure each of the grass species will tolerate varies, but the speaker recommended leaving at least four to six inches of residue for optimum performance.

Other management considerations should be proper weed and pest control and proper fertilization as needed on an annual basis.

Redmon said most cool-season perennials are described as long-lived, but added, "that is at best a vague description of the potential stand longevity." There is no research data to indicate how long a stand of wheatgrass or orchardgrass may stay productive under Oklahoma growing conditions. Some growers, however, are into their fifth growing season with Luna pubescent wheatgrass and Paiute orchardgrass and report no evidence of stand decline to date. Jose tall wheatgrass is also known to persist for many years in Oklahoma, and Lincoln smooth bromegrass has a long history in Kansas.

In conclusion, Redmon recommended that establishment of these cool season perennial grass species only be attempted on small tracts for initial evaluation purposes.

"Never plant more than you can afford to lose until further information is available."

For additional help he suggested contacting local county Extension agents.