Cattle and Deer

Controlled Cattle Grazing Boon to High-Profit Deer

Daniel Boone (left, with Bill Armstrong, a retired Texas wildlife biologist) said the key to quality deer is not only harvesting a certain number but also taking a certain type. (DTN/Progressive Farmer photo by Karl Wolfshohl)

Cattle have been the traditional enterprise on this rugged, old ranch -- which dates back to an 1812 Spanish land grant -- 33 years before Texas became a state. But wildlife rules here. Even with high beef prices, hunting produces more revenue than cattle on the San Pedro Ranch, south of Carrizo Springs, Texas.

Water and native plant and brush species are precious in these Mexico borderlands. High-quality forage for Beefmaster cattle and nutritious food for whitetail deer, quail and other wildlife struggle against drought and nondesirable brush.

"Deer management is pretty easy; it's people management that's hard," foreman Daniel Boone observed as he steered his 4-wheel-drive pickup down a sandy trail, thorny mesquite limbs screeching against the side windows. Boone grew up on the San Pedro and has managed two other ranches.

Even though he carries a name better known from North Carolina and Kentucky frontier days, and does indeed claim to be a blood descendant of the famous frontiersman, his parents came from the state of Coahuila in Mexico. "We are related distantly," said this Daniel Boone. "One of Daniel Boone's nephews came to Texas, and then, at 17, he moved to Mexico. There are a lot of Boones in Mexico, mostly in Coahuila."

Boone's brand of deer management is mostly common sense. The ranch is divided into four deer-management units, with three for lease hunters and one reserved for the Fitzsimons family, which has owned the place since Hugh Fitzsimons Sr. purchased it in 1932. From those units, he simply removes the deer he doesn't want from the herd and leaves superior bucks to produce offspring. Then he lets the bucks grow old enough to reach their genetic potential before they, too, are harvested. It is a practice similar to selecting for high-quality cattle, which the San Pedro has also done with its Beefmasters.


The people management is more complicated. It's difficult to convince hunters to harvest enough deer to preserve the range in this rough, brushy, drought-prone section of Southwest Texas. Leave too many deer, and they'll stress the plants that benefit them and other wildlife. Many hunters, especially those who have no experience in practical biology, think it's impossible that so many whitetails should be harvested.

What's enough? A yearly deer census sets the number. Deer are counted from a helicopter flown over this 24,000-acre spread immediately after hunting season. The aerial survey gives Boone a good sense of the population. He said more specific counts are made on the ground, from hunting blinds and with game cameras. Does and inferior "management bucks" are culled under state permits after the regular season.

"I've done deer management for 30 years," Boone said. "Early on, I fell in with some great biologists and started pushing the envelope. I learned that the more deer we harvested, the better it was. We found that harvesting the right kind of deer is really important, too."


On the San Pedro, range management involves controlling cattle grazing to keep the native forages in a condition that benefits the deer and the use of fire to benefit both cattle and wildlife.

"The way you graze a pasture with cattle affects how the wildlife use it," noted Bill Armstrong, a retired Texas Parks and Wildlife biologist who managed pastures to improve deer substantially on the famed Kerr Wildlife Management Area. Armstrong consults with the San Pedro and other ranches on this subject.

"Young grass, more forbs and a bigger mosaic of plants are better for the deer," Armstrong said. "Deer tend to be a couple of weeks behind the cattle in grazing."

Armstrong said it's easy to let native grasses get too mature without intensive grazing. This is why Boone has instituted a short-duration, intensive-grazing system with the cattle. It keeps the grasses young, tender and higher in protein, which is better for both the cattle and the deer.

"Grass removal allows for forb and browse growth," Armstrong said. "Deer and other wildlife consume the forbs and browse, allowing the pasture to return to grass."


The biologist said the trick is to design pasture rotations with enough time for pastures to recover and return to grass. On the San Pedro, this means a 90- to 120-day rest period, depending on rainfall.

"Deer to some degree are rotating themselves behind the cattle," Armstrong said.

Digestibility of forage has to do with lignin, a component of plant cell walls. Lignin increases as a plant grows older. The deer can eat young grass, but they can't digest old grass because of the lignin.

"Cattle can eat the coarser growth, and then deer follow cattle to eat the new growth," Armstrong said.

"So we're using cattle to create deer food."

Forbs in the native pastures are also known as broadleaf weeds and scorned by some people who value cattle grazing and hay more than deer. Many forbs make excellent deer food, along with browse, which consists of the tender young growth on brush species.

"Generally, forbs don't live long enough to have too much lignification," Armstrong said.

Since they are both ruminants, why can cattle handle coarser grass than deer? It has to do with rate of passage of food through the animal.

"Grass stays in a deer's rumen six to eight hours," Armstrong said. "It stays in a cow's rumen 26 to 28 hours. So a cow has [a day] to break down the nutrients."


Because the livestock and deer do not eat all the forbs, grasses and browse plants, these plants tend to become dominant. Brush control—fire, mechanical or herbicide -- is used at managed intervals to clean up tough, overly mature grasses and to control some brush. The process resets the vegetation mix.

The San Pedro Ranch depends mostly on fire to clean up brush. But a successful controlled burn depends on having enough grass to carry fire. In drought, there often isn't enough grass covering the ground to do the job. When that happens, the ranch uses a mechanical aerator pulled by a bulldozer to encourage grass growth.

Results have been impressive in terms of better deer. "Our genetics have been steadily going uphill," Boone said. "By putting all the harvest data together, the graphs show we're going up, up, up, not only in Boone and Crockett scores but weights. It's exciting to see your management working."

Bucks are in their prime here at 7 to 8 years old, sometimes even older. "They quit breeding so much, and their energy goes to growing antlers," he said. "When their teeth give out, they start going downhill, but I've seen deer that still have decent teeth at 9 or 10 years old. We've harvested some fantastic 9-year-old deer that score in the [Boone and Crockett] 190s."

Body weights are substantially higher. "At the beginning of the season, we used to harvest bucks that weighed 145 pounds field-dressed," Boone said. "Now, we see deer that average 165 pounds and even up to 200 pounds, which is very big for South Texas."

An unforgiving multiyear drought has taken the green out of the Southwest Texas landscape, but proper range management should help the best ranches, such as the San Pedro, to recover quickly when good times return.

"When we get the rains, this country will explode back to life again," Boone said. "It will amaze you."