DARRELL N. UECKERT, Texas Agricultural Experiment Station, San Angelo 76901.
Abstract: Brush Busters was developed in 1995 as a cooperative program of the Texas Agricultural Experiment Station and the Texas Agricultural Extension Service at San Angelo to expedite the adoption by landowners of “select” individual plant treatments for controlling brush. The program stresses the ecological and economic benefits of controlling brush before it matures, thickens and causes a debilitation of the forage resource and soil loss. The Brush Busters’ technical guides are designed to be “layman friendly” so that anyone can effectively control their brush, regardless of previous experience in brush control. Only those methods that routinely kill 76% or more of the plants treated are recommended by Brush Busters. The Brush Busters methods are: (a) environmentally friendly in that herbicides are only applied to the target plants (some methods do not utilize herbicides); (b) more effective than broadcast spraying because the destructive “force” is applied more thoroughly and in greater dosages to the target plants; (c) highly selective, thus allowing the rancher to “take out” the low-value plants while not harming those important to livestock and wildlife; and (d) less expensive than conventional brush control methods when properly applied to the appropriate brush infestations. Brush Busters methods give ranchers a means for “sculpting” the landscape to optimize livestock production as well as wildlife habitat, aesthetics, and the real estate value of the land. Brush Sculptors takes the Brush Busters program to a higher order of resolution in that it is designed specifically for landowners whose primary, or very important secondary, management objective is to increase the production, harvest or enjoyment of wildlife.
The “normal” approach to brush management
Many ranchers appear to ignore their brush until it is mature and dense and a major decline in forage production and livestock production has occurred. Then they hire a contractor with heavy machinery or an aerial herbicide applicator to apply an expensive “reclamation” treatment. After a few years this process is repeated when the brush has again become mature and dense.
The strategy described above may be the “easy” way to manage brush (except for writing the big checks), but it definitely is not an economically or ecologically sound approach. It’s not economically sound because livestock production and net revenue decrease as the brush thickens and matures. Also, the effective treatment life of expensive, reclamation treatments, such as root plowing or tree dozing, is usually not sufficiently long for the increased revenue to pay back the high initial cost. Furthermore, considerable risk is associated with some conventional brush treatments. There is substantial probability that the level of brush kill will not satisfy the rancher’s expectations or management objectives.
The approach described above is not ecologically sound because as brush matures and thickens the understory forage species (grasses and desirable forbs and browse plants) are weakened by the brush competition. Very often, the desirable species are replaced by less desirable or noxious plant species. When this occurs, part of the topsoil is often lost to erosion, which permanently decreases the potential of the land to produce forage. Also, many of the reclamation brush treatments are non-selective, resulting in serious collateral damage to desirable forbs (weeds) and browse plants that are important food plants or cover for both livestock and wildlife.
Brush Busters: a common sense approach to brush management
The common sense, alternative approach is to control undesirable brush:
1) before it causes debilitation of your forage and soil resources and a decline in animal production;
2) while the brush is in its most vulnerable growth stage; and before the brush produces seeds that will continue to germinate and re-infest your rangeland or improved pastures for years.
Remember these important facts:
1) juvenile brush plants are easier and less expensive to kill than mature brush plants;
2) capital outlay can usually be minimized by controlling brush in the seedling or sapling growth stages and before dense stands develop;
3) there are usually more treatment alternatives for controlling brush seedlings and saplings than for controlling dense stands of mature brush; and
4) controlling brush in its early growth stages prevents a decline in the health and production of the forage resource and allows you to maintain a relatively constant level of livestock and wildlife production.
Many effective control methods are available for selective control of brush seedlings, saplings and regrowth that returns following conventional brush control practices, as well as mature brush plants (Welch 1997). These treatments include many individual plant treatments that are being widely used by ranchers and their family members, ranch laborers, or seasonal workers in “do-it-yourself” programs. However, the efficacy, economics, labor-efficiency, and acceptability of individual plant treatments have been greatly improved by several new innovations, including:
1) all-terrain vehicles (4-wheelers) equipped with sprayers;
2) light-weight, backpack sprayers;
3) special nozzles that minimize herbicide use;
4) highly effective herbicides; and
5) spray-marking dye that helps you avoid missing brush plants or spraying the same plants twice.
Brush Busters methods
The Brush Busters methods apply the destructive force, whether it is a herbicide leaf spray, stem spray, or soil spot application, or the swift stroke of a grubbing hoe, with precision to selected targets. This do-it-yourself technology is ideally suited for killing brush in the early stages of its invasion into grasslands or improved pastures and for maintenance or “follow-up” control following conventional brush control treatments. Brush Busters methods are:
1) environmentally friendly when applied to appropriate brush densities and sizes, because less total herbicide is applied per acre. Also, collateral damage to desirable plants is essentially eliminated because the herbicide or other force is applied directly to the target plants. The herbicides recommended by Brush Busters are less toxic to wildlife, livestock, and humans than table salt or aspirin (Hanselka et al. 1994);
2) more effective than broadcast spraying because of more thorough coverage and application of greater herbicide dosages to the target;
3) highly selective, thus allowing a rancher to sculpt his landscape to optimize livestock production as well as wildlife habitat, aesthetics, and the real estate value of the land; and
4) less expensive than conventional brush control using heavy equipment or broadcast herbicide applications.
The Brush Busters program
Brush Busters is a cooperative program of the Texas Agricultural Experiment Station and the Texas Agricultural Extension Service to expedite the adoption and safe use of do-it-yourself brush management technology by ranchers and other landowners. The program is endorsed by the U.S.D.A.- Natural Resources Conservation Service, DowElanco, and DuPont. The primary goal of Brush Busters is to make brush control user-friendly, safe, and simple so that anyone, regardless of past experience, education, or training can use the available technology effectively to manage his/her own brush problems.
Mesquite, cedar (juniper) and pricklypear have been targeted during 1995, 1996 and 1997, respectively, in the Brush Busters program. Brush Busters promotes only the most highly effective individual plant treatments that are available – those that routinely kill 76 to 100% of the plants treated (Welch 1997). Large demonstration/research plots were established for each brush species at five highly visible locations, and these were showcased with large, professionally designed signs to catch the eye of landowners. Information leaflets are designed with easy-to-follow instructions for each of the target brush species (McGinty and Ueckert 1995, 1996, Ueckert and McGinty 1997). The leaflets tell precisely how much herbicide and other ingredients to use for common spray tank sizes. Videos were made to demonstrate the Brush Busters “select” control methods for each species (McGinty et al. 1995, Ueckert et al, 1996). An interactive CD-ROM was produced on the Brush Busters mesquite control methods, courtesy of DowElanco, for land owners or resource managers who use high-powered computers (DowElanco et al. 1996). These items are available through County Extension Offices, Natural Resource Conservation Service offices, retail herbicide dealers and DowElanco’s regional representatives. Brush Busters notebooks have been made available to County Extension Agents to facilitate the development of county-level Brush Busters programs and demonstrations.
How to beat mesquite
The Brush Busters “How to Beat Mesquite” program promotes only two “select” treatments for controlling mesquite (McGinty and Ueckert 1995). One is a “stem spray” containing 15 or 25% Remedy herbicide in a diesel fuel carrier. The second is a “leaf spray” containing 1/2% Reclaim herbicide + 1/2% Remedy herbicide. Results from the large demonstration/research plots treated in 1995 showed the following:
1) The stem spray method (l5% Remedy + 85% diesel fuel) was capable of treating up to about 300 mesquite/acre before approaching the cost and quantity of herbicide applied using the most effective broadcast aerial treatments. Cost per mesquite plant treated averaged 11 cents (range 6 to 15 cents). Cost per acre averaged $18.50 (range $6.20 to $25/acre). The average mesquite density was 196/acre (range 43 to 327/acre).
2) The leaf spray method treated over 400 mesquite/acre before reaching this same threshold. Cost per mesquite plant treated averaged 8.2 cents (range 5 to 15 cents). Cost per acre averaged $l6.76 (range $6.80 to $34.20/acre). The average mesquite density was 244/acre (range 45 to 461/acre).
3)Mesquite rootkill after 2 years averaged 80% for the leaf spray and 80% for the stem spray.
How to master cedar
The Brush Busters “How to Master Cedar” program promotes three “select” treatments for controlling redberry and blueberry cedar (McGinty and Ueckert 1996). One is a “leaf spray” containing 1% Tordon 22K herbicide. (Note: a Pesticide Applicator License from the Texas Department of Agriculture is required to purchase and use Tordon 22K). The second is a “soil spot spray” that uses undiluted Velpar L herbicide. And the third is the “top removal” method that utilizes a grubbing hoe, pruning shears or an axe. Results from the large demonstration/research plots treated in 1996 showed the following:
1) Cost for the leaf spray method averaged 12.9 cents per cedar treated (range 7 to 19 cents/cedar). Average cost per acre treated was $20.90 (range $9.70 to $35.60/acre). Average cedar density was 172/acre (range 82 to 319/acre).
2) Cost for the soil spot spray method averaged 6.4 cents per cedar treated (range 5 to 8 cents/cedar). Average cost per acre treated was $13.25 (range $9.60 to $16.90/acre). Average cedar density was 207/acre (range 182-246/acre).
3) Rootkill of cedar after 1 year averaged 89% for the leaf spray method and 85% for the soil spot spray.
How to take care of pricklypear
The Brush Busters “How to Take Care of Pricklypear and other cacti” program promotes only one “select” herbicide treatment: a pad or stem spray containing 1% Tordon 22K and 5% diesel fuel (Ueckert and McGinty 1997). This spray is effective on pricklypear, tasajillo, cholla and other cacti. A top removal method is recommended for pricklypear that utilizes a shovel or grubbing hoe. Large demon-stration/research plots on pricklypear will be established during late summer of 1997. Results from pasture-size plots treated during 1994 – 1996 have shown the following results:
1) Cost for treating 533 pricklypear plants/acre was $12.60/acre.
2) Cost for treating 100 pricklypear/acre was $3.91/acre.
3) Cost for treating pricklypear that survived after the second of two prescribed fires averaged $2.80/acre.
Costs for the Brush Busters methods escalate rapidly as size of the plants and their abundance or density (number/acre) increase, so obviously these methods are not applicable for all brush infestations. However, they are ideally suited for controlling small brush or cacti that have recently invaded your grasslands or improved pastures, and for maintenance control of seedlings and resprouts that appear soon after pastures have been treated with mechanical methods or by broadcast herbicide applications. The Brush Busters methods may also be suited for selective control of mature brush plants.
If your brush is too large or dense for the Brush Busters methods, you’ll have to “bite the bullet” and install one of the expensive “reclamation” treatments as the initial phase of your brush management program. Be certain that you adequately plan your reclamation treatments so you do not damage the wildlife habitat value of your rangeland. Carefully select and delineate the areas where brush is to be left undisturbed, and effectively communicate this information to your contractor. Then, be present when the work is being done to be certain your instructions are being followed to the letter.
After reclamation brush control projects are completed, the common sense way to maintain the level of brush control that you desire is to use Brush Busters methods for follow-up, maintenance control of brush resprouts, seedlings and saplings missed by the contractor, and seedlings that germinate from seeds already in the soil. For example, we have found prescribed fire and the Brush Busters methods to be highly complementary. Fire can be used as the initial treatment to reduce the abundance and stature (canopy height and volume) of cedar, mesquite and pricklypear plants, then after two or three years use Brush Busters methods to “mop up”, i.e. to kill the target plants that survived the fire. We usually leave the large mesquite that were not top-killed by fire. The result is an aesthetically pleasing “mesquite savanna” developed for a cost of about $11/acre. This cost looks good compared to the going rate of $25/acre or more for aerial spraying with the herbicides that are capable of killing a substantial percentage of the mesquite. Similarly, we have developed pricklypear-free grasslands, to eliminate the “pearmouth” health problem in sheep flocks, by utilizing Brush Busters methods, at costs of $2.50 to $4/acre, following the second of two prescribed fires. This cost is also attractive compared to the going rate of $21/acre or more for aerial spraying with Tordon 22K for pricklypear control.
Regardless of whether you use conventional “reclamation” brush treatments or Brush Busters methods, remember: brush management is not a one-time operation! You’ll have to go over your rangeland or improved pastures from time to time to take out the target plants that were missed, that resprout, or that germinate and establish from seed already in the soil. Everyone will miss a few (usually about 5%) of the target plants, and there is no treatment that is 100% effective! Just don’t wait too long and allow your brush to mature before you apply your follow-up treatments! Also, remember that the same practices which are effective for improving brush-infested rangelands for livestock production can also be effective for improving wildlife habitat if they are used appropriately.
Be sure you do some serious long-range planning before you initiate a brush management program! First, be certain that you have, or that you will implement, a program of proper grazing management. Consider the importance (or potential future importance) of wildlife and aesthetics in your ranch operation. White-tailed deer and quail need some brush for food and cover. Rio Grande turkeys need large trees for roosting sites. Quail may nest in pricklypear colonies if suitable bunchgrass nesting sites are lacking (Slater 1996). Pricklypear may also be useful for emergency livestock feed during droughts or winter seasons, and it is an important food for white-tailed deer and other wildlife species (Hanselka and Paschal 1989). Cedar (juniper) is important as food and cover for a variety of wildlife species (Rollins and Armstrong 1997). Also, the real estate value of rangeland can be seriously reduced if the large trees (such as live oak, post oak, Spanish oak, etc.) and important browse plants are removed from fence to fence because land values in some regions are correlated more with the land’s potential for recreation (e.g. hunting) than with its potential for livestock production.
Brush Busters methods are ideally suited for managing brush-infested rangeland for multiple uses. They allow you to take out the plants you want to kill, and leave undamaged those you want to keep. They make it possible to establish the type of landscape that best fits your management objectives. With a little planning, you can develop a mosaic of grasslands interspersed with savannas and woodlands, with natural boundaries that conform to the terrain or other natural features. The Brush Busters methods allow you to retain protective brush cover (coverts) of the appropriate size and density for your wildlife populations. Few commercial brush control contractors would likely have the necessary knowledge and patience to “sculpt” brush-infested rangelands for wildlife habitat improvement. Brush Busters is the common sense program for ranchers, and the Brush Busters methods meet all the requirements for minimizing risks to wildlife populations (Hanselka et al. 1994).
The Brush Sculptors concept and program evolved from the growing interest in wildlife among the general public and landowners, and the increasing economic value of wildlife to landowners. The critical importance of “brush”, biological and landscape diversity, “edge effect”, escape or resting cover, and feeding areas to wildlife populations dictates that brush management be planned and executed very carefully whenever wildlife production is an important management objective of the landowner.
The Brush Sculptors program is designed specifically for landowners whose primary, or significant secondary, management objective is to produce more and healthier wildlife, to increase net revenue from their wildlife resource, or simply to enhance their personal “wildlife experience”. Brush Sculptors emphasizes creating the habitat(s) most favorable for the wildlife species of interest to the landowner (or his clientele), and utilizes Brush Busters methods, conventional brush control technologies, or in some cases the planting and nurturing of “brush” to achieve the goals of the landowner.
I would like to conclude this discussion with a very important fact: brush control alone, regardless of whether Brush Busters methods or conventional methods are used, will not guarantee long-term improvement in rangeland for either livestock or wildlife production. The “basic tool” that must accompany brush management for sustaining or improving rangeland is proper grazing management. Proper grazing management includes grazing at the proper stocking rate and providing periodic rest, preferably about 90 to 120 days, to pastures during the growing season. A landowner’s most important responsibility is to assure that his animal numbers, whether they are white-tailed deer of white-faced steers, do not exceed the carrying capacity of his rangeland.
A landowner should understand that his soils and desirable grasses, forbs and browse plants are the basic building blocks for his production system. The soil cannot support optimal plant growth if the surface layer of soil is lost to erosion. The desirable plants cannot efficiently capture rainfall, soil nutrients, or the sun’s energy through photosynthesis if they have been excessively grazed and lack adequate leaf surface area and deep root systems. Adequate standing vegetation and litter (mulch) is essential for achieving infiltration of rainfall into the soil upon which it falls. Desirable grasses, forbs, and browse plants that are vigorous, healthy, and reproducing can help prevent establishment and invasion of undesirable brush seedlings through the process of competition. Ranchers who understand their production system and who try to work with, rather than against, the natural processes are the ones who will remain in the ranching business for the long haul. The brush problem on Texas rangelands is largely due to the fact that landowners and managers have neither fully understood their production system nor worked with the natural processes.
DowElanco, A. McGinty, D. Ueckert, S. Byrns, N. McGeeney. 1996. Brush Busters – how to beat mesquite. CD-ROM. DowElanco. Indianapolis, Indiana.
Hanselka, C.W., D. Rollins, and J. Winn. 1994. Reducing herbicide risks to wildlife on rangeland. Texas Agric. Ext. Serv.
Hanselka, C.W. and J.C. Paschal. 1989. Developing prickly pear as a forage, fruit and vegetable resource. Texas Agric. Ext. Serv. College Station, TX.
McGinty, A. and D. Ueckert. 1995. Brush Busters – how to beat mesquite. Texas Agric. Ext. Serv. & Texas Agric. Exp. Sta. Leaflet L-5144.
McGinty, A., D. Ueckert, and S. Byrns. 1995. Brush Busters – how to beat mesquite. 15-min. video. Texas Agric. Ext. Serv. & Texas Agric. Exp. Sta. College Station, TX.
McGinty, A. and D. Ueckert. 1996. Brush Busters – how to master cedar. Texas Agric. Ext. Serv. & Texas Agric. Exp. Sta. Leaflet L-5160.
Rollins, D. and B. Armstrong. 1997. Cedar through the eyes of wildlife. In: C.A. Taylor (ed.). 1997 Juniper Symposium Proceedings. Texas Agric. Exp. Sta., Texas A&M Res. & Ext. Center – San Angelo Tech. Rep. 97-1.
Slater, S.C. 1996. An evaluation of pricklypear (Opuntia spp.) as a predator deterrent in nest site selection by northern bobwhite (Colinus virginianus). M.S. Thesis. Angelo State University. San Angelo, TX. 52p.
Ueckert, D. and A. McGinty. 1997. Brush Busters – how to take care of pricklypear and other cacti. Texas Agric. Exp. Sta. & Texas Agric. Ext. Serv. Leaflet L-5171.
Ueckert, D., A. McGinty, and S. Byrns. 1997. Brush Busters – how to master cedar. 12.5-min. video Texas Agric. Ext. Serv. & Texas Agric. Exp. Sta. College Station, TX.
Welch, T.G. 1995. Chemical weed and brush control – suggestions for rangeland. Texas Agric. Ext. Serv. Bull. B-1466.Dale Rollins, Professor and Extension Wildlife Specialist
Updated: Mar. 18, 1997