One of the most common pasture management problem ranchers face in South Texas is weed and brush infestation.
Controlling South Texas brush is not an easy task, but many area ranchers are finding ways to keep it at bay.
Weed species effectively compete with more desirable forage species for sunlight, moisture, and soil nutrients, and depending on a rancher’s goals and objectives, brush is usually a thorn in their side.
“The Coastal Bend area used to be largely grass land, and over a period of time, due to a number of factors, mainly the reduction of natural fires on our landscape, and over grazing by livestock, we have seen an increase in the encroachment of these evasive brush or tree species across our pastures, ” said Texas A&M Agrilife Extension Range Specialist Megan Clayton.
“What we have here is mesquite and huisache, and it is an ongoing problem every year. Because of the wildlife, the birds, deer, they will eat some of the beans and spread it all over the pasture. It is a never-ending situation,” said cattle rancher Leon Little.
Some of this brush may be good if wildlife is a management goal, but not for ranchers who are trying to manage the brush so that they can grow more grass for grazing livestock.
“The cattle have depleted. I have 4 pastures, and they have depleted all of the pastures, all of the grasses, except for this pasture here,” said Little.
Brush takes up valuable moisture, sunlight and space that grass could use to produce adequate forage for the livestock, and controlling it can be costly.
“In order to buy the chemicals that we use, you have to have a pesticide license to purchase the restricted pesticides. This chemical is not cheap, some of these chemicals are $90 a gallon,” said Little.
Weed infestation generally occurs due to poor management or uncontrollable conditions such as drought.
“Moving forward, Texas A&M Extension is really extensively looking into research that would provide alternative methods for controlling these brush species to make it easier and more effective for these land owners,”said Clayton.
The treatment methods have varied over the years, from mechanical methods such as root plowing and grubbing to aerial spraying with a myriad of different herbicides with mixed results.
Mesquite and other brush also prevent rainfall from reaching the soil. In an average 30-inch rainfall area, dense stands of brush allow only about 20 percent of rain to reach the soil’s root zone.
The rest remains on the branches or litter and finally evaporates. By contrast, short grasses allow 80-90 percent of water to reach the soil.