Brush plants
Useless shrubs or brush on the range lower the production of native grasses and thus reduce livestock production. The brush plants use moisture, nutrients and space that should be used by desirable forage plants. Removing undesirable brush plants can increase both forage and livestock production. Not all brush species are bad; for example, shrubs are very important on the winter range and bitterbrush furnishes valuable forage for both wildlife and livestock when snow is on the ground. Generally, it is a good idea to keep shrubs on your winter range if they grow there naturally.

There are several methods of controlling brush, commonly using herbicides, mechanical implements and fire. The herbicides are usually liquid materials that are sprayed on the brush leaves by aircraft or machines on the ground. A common herbicide is 2,4-D. Soil sterilants may be used to kill small weed patches on high value land. Recommendations for chemical control of undesirable plants change frequently, as new information and herbicides become available. For the latest recommendations, check with you extension agent. Follow instructions carefully.

Mechanical methods of controlling brush include rotary mowing, bulldozing, railing, chaining, beating and plowing. They vary widely in their effectiveness, depending upon species, topography, season used, soil moisture and associated plants.

Fire is another method for brush control, but this can be very dangerous, even when carefully planned. Never try to burn brush without a permit from the local fire warden, who will require you to have a complete plan. It covers: 1) construction of fire lines; 2) suitable crew available to control the fire; 3) equipment such as bulldozers, graders and tank trucks standing by; 4) proper weather reports, including predicted wind velocities; 5) seed ready for planting; and 6) bond provided to cover damages. Many people are discouraged by all of these restrictions and use some other method of control.

Any area that has been treated by brush control measures should be deferred from grazing the first growing season, or longer, so native grasses can get a good start in the space left by the brush. Large amounts of brush on the piece of rangeland may well indicate poor management in the past. After brush is controlled, wise management practices will be necessary to prevent it from reinvading the rangeland.

Poisonous plants
Many poisonous range plants can be controlled by use of herbicides. Proper timing and soil moisture conditions are necessary for good control. Protection of desirable forage plants is important. Check with your extension agent for recommendations on chemical control of poisonous plants.

Make sure that desirable plants replace the ones killed. Seed desirable forage plants or defer grazing as necessary. Some poisonous species start growing earlier in the spring than more desirable range plants. In this case, deferred grazing is a good practice.

Just as with range seeding, your work in controlling range plants should be followed through with good grazing management. The range should be rested and, if necessary, even seeded to help nature replace the undesirable plants with more productive plants.