New Mexico rangelands sustain many species of weeds and brush.  Weed and brush intrusion can be caused by several factors, the major players being drought and over grazing.
When considering brush management one must consider several factors: methods, timing, and follow up maintenance of the rangeland.  A rangeland manager must have a specific goal in mind; taking into account all ranching enterprises and the environment.  Finally, managers must consider costs.

Here are the top top 10 misconceptions about brush control:

“Bad Brush”
Not all brush and weeds are bad and attempting to control undesirables can lead to damaging many of the desirable plants needed for wildlife species.  Wildlife such as deer depend on woody plants for food and cover.  In addition, take into consideration the spacing and layout of such brush.  “Honey Holes” can be developed or enhanced through proper management.  Plant I.D. is important to know and be able to categorize which plants benefit which wildlife species.

“Eradicating brush equals more grass”
For rangeland to recover or grasses to grow, there must be some sort of seed bank or reserve of desirable plants in the area.  Post treatment management of the area is very important.  Time must be given for plants to grow, re-establish, and seed.  If grazing is allowed too early there will be no seed bank and undesirable plants will make a quick recovery.  Low rainfall or drought conditions should also be taken into account.

“Killing brush will allow me to increase my income”
Weed and brush control is costly.  Things to consider are cost per acre, life of treatment, forage response, risk, and future costs of maintenance treatments. 

“One shot will do”
Many brush treatments are short lived without a long term management plan.  After your initial treatment your “follow ups” should be less costly with the beginning of recovering your costs.   Best treatments you can hope for are 80% to 85% kill.  Follow up with other treatments to make up the rest.

“A little does a little good, a lot does alotta good”
Using more than the recommended rate will not ensure better success.  It may seem like you did a good job but at a higher cost.  Recommended rates are derived from research and tests and are calculated for the lowest cost and least impact on the environment.  Consult manufacturer, NRCS, Coop. Extension.

“I heard it through the grapevine”
Much of our knowledge comes from friends, neighbors, relatives or hear say.  Don’t take chances!  Read the label, consult the experts. (NRCS, Extension, Dealer, etc.)  Untested recommendations or rates could be hazardous to you, your crop, or the environment.

“Wait until it gets worth killing”
It is easier and less costly to treat brush and weeds when they are small  (saplings, seedlings).  Small brush is less dense and overall takes less chemical to treat.  Down turn of desirable plants increases as brush increases in size and density.  In addition, large plants take up more light, nutrients, and water.

“Let’s spray the whole pasture”
Not all areas of your rangeland have the potential to grow lush grass species.  Leave the ridges, slopes and hill tops to wildlife.  Treat those areas with deep, high organic soils more capable of recovering and sustaining the plants you are wanting.

“A Sea of Grass”
Chemical or mechanical brush control isn’t the definite cure to better pasture and more desirable plant communities.  Climate and plant characteristics are the greatest factors in the success of an application.  Management is also key.  Rest the given pasture to allow for establishment.  Consider stocking rates, long range planning, and monitoring.  Leave 350 lbs. to 750 lbs. residual forage/ac for short and mid grass communities.

“Herbicides are unhealthy to the
environment”
Herbicides are invaluable in the control and management of brush and weeds.  Toxicity levels are outlined in the product labels.  Always read the label and follow directions accordingly.  Consult professionals, NRCS, or Extension personnel.  Minimize risks to yourself and the environment.

Tom Dominguez is an agent with the Quay County Extension, NMSU Extension Service. He can be reached by emailing todomingu@nmsu.edu or calling 461-0562.