White-tailed deer hunters have the chance to perform a labor of love on Labor Day weekend – planting winter supplemental feed plots.

"With fall-planted cowpeas, there's a narrow window of opportunity from Sept.1 through about Sept 15," said Dr. Billy Higginbotham, Texas Cooperative Extension fisheries and wildlife specialist. "After that, you'll see diminishing returns."

Higginbotham and Dr. Ray Smith, a Texas Agricultural Experiment Station legume breeder, have identified an improved a combination of oats and arrowleaf clover that make up for the deficiencies of traditional plantings.
"Based on the results of our trials, we're now recommending a combination seeding rate of 40 pounds per acre of forage cowpeas, 40 pounds of oats and 10 pounds of arrowleaf clover," Higginbotham said.

"In our trials, this triple mix resulted in over 3,000 pounds per acre of cowpea production by Thanksgiving; over 5,000 pounds per acre of oats by April, better than 3,500 pounds per acre of arrowleaf clover in April – with even higher yields possible in May," Smith said. Supplemental feeding plots usually involve planting a small grain such as oats. But in East Texas, oats do not start producing until November, so these plots had nothing to attract deer during bow hunting season, Sept. 27-Oct. 26.

"What we needed was a warm and cool season combination to enhance the potential to attract deer early in the fall," Higginbotham said.

Commercially sold mixtures often include some sort of early producing forage mixture, usually of the brassica family, such as rape or turnip.

"Many different commercial mixtures are available," Smith said. "But none provide the combination of early fall forage production and full-season production that this new mix does."

Also, Smith said, an open time was left when no forages were producing.

"That's the main reason we included oats in the mixture. They act as a winter bridge between the cowpeas and the arrowleaf clover," Smith said.

Cowpeas, on the other hand, were a proven forage for white-tailed deer. But they are usually planted in the spring to provide extra protein during rutting season, Higginbotham said.

With these factors in mind, in 2002 Higginbotham and Smith began testing various ratios of seed in early September plantings. Earlier trials had shown that Iron and Clay cowpeas and Apache arrowleaf clover were a winning combination.

"In 2001 trials, the cowpeas had produced almost 2 tons of dry weight forage per acre!" Higginbotham said. "By late May 2002, the arrowleaf clover stands also produced almost 2 tons of forage per acre. The only problem was that gap in forage availability from the first frost in late November when the cowpeas disappeared to when the clover came on strong."

Smith chose Heavy Grazer oats to fill the December to March gap. Oats are cold tolerant and perform well if planted in late August to early September, "as long as there is adequate soil moisture at planting," Smith said.
What remained was to determine the optimal combination of seeding rates. Another unknown factor was if the varieties would compete with each for soil nutrients and moisture when planted together.

"Call it 'variety compatibility'," Higginbotham said. "There are lots of seed combinations on the market today, but most do no not undergo this battery of trials to determine how much of each is just right."

Higginbotham and Smith tried six seeding rate combinations for the cowpea and oat mixtures. The arrowleaf clover component was held constant at 10 pounds per acre throughout the trial.

Along the way, they had to contend with such common discouragements as weeds, low fall moisture and, of course, vandalism by feral hogs.

Where the trials weren't destroyed by hogs, most of the combinations proved effective. But the one mixture stood out in terms of superior production from November through March, Higginbotham said. The arrowleaf complemented the oats and cowpeas and provided growth well after spring green-up.

"This is most important by the month of June," Higginbotham said. "It helps 'buy time' until spring-planted crops can become available to deer."