Brush management may seem like a place to cut corners in tough economic times, but Texas AgriLife Extension Service specialists say doing so will cost ranchers more in the long run.
"The cost of doing nothing is very expensive,” said Stan Bevers, AgriLife Extension economist.
Ranchers typically budget some for brush control, generally about $1 per acre per year, so it adds up substantially, Bevers said.
"With the rising cost of running cattle on ranches, managers are asking where managing brush fits,” he said. "It is going to be increasingly more difficult to find dollars for brush control. But it is a situation where brush doesn't know or care that there is a financial crisis going on. It's going to keep growing.”
More brush equates to lower productivity, he said. A lot of brush growth happens slowly, and eventually can reduce carrying capacity for the ranch.
Determining the most economical method of brush control may be a more difficult decision, Bevers said. Fire is still the cheapest route for brush control, but after several seasons of wildfires, it makes many people nervous.
J.F. Cadenhead, AgriLife Extension range specialist, said an integration of mechanical, burning and spraying will most likely be needed to get good control of the brush.
"First, you have to determine what the goals are for the ranch – will it be used primarily for cattle grazing, a mixture of cattle and wildlife, or primarily wildlife,” Cadenhead said.
"If you are getting over 50% brush cover, you are getting behind if you are in the livestock business,” he said. "But if you are integrating wildlife, you may need from 50 to 60% coverage. Remember, wildlife need some open spaces also.”
The timing of treatment will depend on the method planned and maintenance program, Cadenhead said.
Burning is typically done in late winter or early spring, he said. Ranchers need to plan in advance for the cutting of fire guards during the off season, and make sure arrangements are made for the cattle.
Cattle should be taken off the land for almost a whole growing season before burning to allow enough grass fuel to grow, Cadenhead said. And then the land has to be deferred after the burn from early spring until the grass gets 6 to 8 inches tall, which could take until mid-summer, depending on the moisture.
Chemical work and mechanical cutting and spraying are primarily done in the summer when plants are in mature growth, he said. The mechanical brush work, such as grubbing, can be done in the winter with good soil moisture conditions.
Depending on the severity of the brush cover, Cadenhead said it might be necessary to use mechanical or chemical operations to open up a pasture enough to let grass grow and build the fuel base needed for a good prescribed burn.
"Individual plant treatment, once the brushy areas are opened up and/or burned, can then be used for maintenance,” he said.
Cadenhead said the cover layer must be allowed to recover to protect the soil from erosion and to provide adequate time for microbial degradation of the plant matter on top of the soil that will help in nutrient cycling.
"You may not want to burn any closer than 5 or 6 years apart,” he said.