Rangelands with their varied ecological sites and plant diversity are typically managed for multiple uses such as providing forage for grazing cattle, habitat for wildlife and clean water to name a few. Sustainable rangeland management is rooted in maintaining vegetation composition, cover and production.
Across the globe, a common challenge on rangelands is maintaining vegetation within a desirable mix of herbaceous and woody plants; a change in this mix toward woody plants has been striking in the last 150 years. A number of drivers, including climate, grazing, browsing, fire, atmospheric carbon dioxide and nitrogen deposition, have been proposed as drivers of this change. What exactly constitutes a desirable mix of herbaceous and woody plants for you and your rangelands is a question that is beyond the scope of this article. More often than not, if you are managing rangelands on the Southern Great Plains, woody plants are encroaching.
There is a tendency to ignore the brush encroachment until the point in time when the woody stand has become a serious problem. At first, there are just a few scattered woody plants and it's hard to see any harm they are causing. Then, those plants grow larger and new plants establish until, like the fabled frog in boiling water, the effects of steady encroachment are clear. Often, the herbaceous plants are weakened as woody plants out compete them for light and water. Since the transformation has been so gradual, stocking rates were likely never adjusted to account for the lost herbaceous production, and the remaining grazeable acres have been overgrazed. However, waiting until this point in time will require expensive reclamation treatments.
A better, more economical approach is to 1) recognize early on the risk these woody species pose to rob you of valuable forage and the biotic integrity of your rangelands and 2) attack the brush while it is most vulnerable and before any harm is suffered. Juvenile brush plants are typically less costly to kill than are mature brush plants. For example, fire alone is very effective at controlling Eastern Red-cedar that is less than 6 feet tall, but once it has reached a height of 20 feet, the likelihood of controlling these trees with a single fire is significantly reduced and mechanical treatment is often necessary. If the density of the brush species is less than about 250 plants per acre, individual plant treatment with an efficacious herbicide is a good economical option. Individual plant treatments allow you to specifically control the undesirable brush species without injuring important forb species that often accompany broadcast treatments. When it comes to brush problems, an ounce of prevention is worth a pound of cure.