Wildlife Habitat Management on Former CRP Lands
Scott Lutz, Gary L. Valentine, Steve Nelle, Dale Rollins, Charles Coffman, Gene Miller
Options For Managing Expired CRP Land For Wildlife | Maximum Wildlife Benefit | Dual Wildlife and Livestock Production
Dual Cropland and Wildlife Habitat | Cropland Managed for Secondary Wildlife Value | Summary
The Conservation Reserve Program (CRP) was authorized by the 1985 Food Security Act, more commonly called the 1985 “Farm Bill.” Its primary purpose was to reduce soil erosion from highly erodible crop lands by removing these fields from production of annual crops and establishing permanent vegetation. Improved wildlife habitat was another benefit of this program.
Some 3.7 million acres in northwest Texas under more than 17,000 contracts were restored to permanent vegetation. Introduced grasses (weeping lovegrass, kleingrass and old world bluestems) and native species (sideoats grama, blue grama and native bluestems) established either singly or in mixtures are the prevalent species.
CRP contracts begin to expire in late 1995. Many of the lands are expected to return to annual crop production unless USDA offers incentives that encourage retention of permanent vegetative cover. The most highly erodible lands should remain in permanent vegetative cover to benefit soil and wildlife resources.
Portions of highly erodible fields returned to annual crop production can offer valuable habitat, but only if permanent cover is retained in key areas within fields. Extensive areas of grass can be improved for many species of wildlife by diversifying vegetative cover with management practices that favor wildlife. Many species of wildlife inhabit northwest Texas and will be impacted by landowners’ management decisions for their CRP lands. Any decision will benefit some species more than others; in fact, some species may be adversely affected. For instance, retaining large fields in grass may favor several species of songbirds and prairie chickens, but bobwhite and scaled quail populations will benefit only around field edges. The purpose of this note is to provide landowners management alternatives that will benefit wildlife.
Habitat management alternatives discussed in this note will benefit game species such as ring-necked pheasant, bobwhite and scaled quail, mourning dove, lesser prairie chicken, wild turkey, pronghorn antelope, white-tailed deer, mule deer, ducks and geese. Nongame wildlife, such as grassland songbirds, will also benefit from these practices.
Options For Managing Expired CRP Land For Wildlife
Landowners facing the expiration of CRP payments and obligations may choose several land management options that will provide varying wildlife benefits. These options include: 1) managing entire acreage exclusively for maximum wildlife benefits; 2) manage land for dual livestock and wildlife production; 3) converting a portion of acreage to cropland while retaining parts in permanent habitat; and 4) converting entire acreage to cropland, managing it for wildlife.
1) Maximum Wildlife Benefit.
This option requires no fence construction. Water development is not essential, but would be desirable to improve the value for deer and turkey.
To prevent the undesirable buildup of excessive litter, grass stands will require periodic burning. Ideally, prescribed burning could be used annually on 20% to 33% of the acreage so that some portions are always freshly burned while other areas have one or more years grass growth. Acreage should be divided with fireguards so that the size of burns is kept relatively small. The desired effect should resemble a patchwork quilt or a mosaic design. Since woody vegetation is critical to wildlife on CRP land, fireguards or fire retardants should be used to protect areas where brush or trees are becoming established. In order to favor the growth of forbs, burns should be conducted as early as possible after frost. Late winter burning encourages grass and discourages forbs.
Fireguards can serve the dual purpose of controlling fire and as annual food plots or disked strips for weed stimulation. The soil disturbance caused by creating firelanes or roads fosters the growth of “weeds” (forbs). Many of these forbs are important seed producers for gamebirds. Some forbs, like Mexican fireweed (Kochia) , attract different kinds of insects, especially grasshoppers, that are critical to the growth and development of young gamebirds. Annual grasses like Texas signalgrass that produce seeds for birds are also favored by periodic soil disturbance.
If you plan to disk a fireguard, we recommend the use of a tandem disk during January or February. If the grass stand is heavy, repeated disking may be necessary to obtain the degree of soil disturbance desired. Disking will provide the best forb response in sandy soils. Broadcast applications (100 to 200 lbs/ac) of a phosphate fertilizer like ammonium phosphate (11-48-0) will increase the production of forbs, and will also enhance their palatability to deer. Disking needs to be conducted annually or biannually in order to ensure sustained production from these forbs and grasses. The key to maximum wildlife production on CRP land is to have as many different kinds of habitat with the greatest variety of plant types and cover types all arranged as closely as possible.
Many farms have existing woody cover adjacent to CRP fields or near CRP fields. These areas of woody cover can and should be used in developing wildlife habitat. Areas include windbreaks, playas, “odd areas” and fence rows. Odd areas include equipment yards, old homesteads or any other non-cultivated area. Established windbreaks should be managed to allow herbaceous vegetation (i.e. grass and forbs) to become established and be maintained. Older windbreaks may need to be renovated to provide the best habitat. Renovation may involve removal and replacement of dead plants, thinning of existing plants to improve vigor and planting new rows to obtain proper windbreak functions and provide needed habitat.
Existing woody and herbaceous vegetation (including some cattails) on playas serves an important role for wildlife habitat in many CRP fields. Playas provide food and cover for wildlife and are extremely valuable in extensively cropped areas. To protect these woody plants, the playa should not be burned (occasional prescribed burns may be useful), overgrazed, treated with herbicides, or shredded.
The “edge” between CRP fields and brushy rangeland provides both food and shelter for gamebirds like quail and pheasants. Both of these gamebirds use brush for loafing and thermal cover. While the grasses on CRP lands may suffice for thermal and nesting cover, loafing cover is usually lacking. Ideal loafing cover for bobwhites should provide overhead screening cover (for protection from hawks), but be fairly open at ground level to allow detection of mammalian predators. Brush species that make good loafing coverts in west Texas include sandplum (wild plum), lotebush, skunkbush, litteleaf sumac, whitebrush, some mesquite, and four-winged saltbush. Junipers typically do not make preferred loafing cover, but offer excellent thermal cover in winter. In some instances, pricklypear (especially the Engelmann and Lindheimer varieties) or cholla may provide loafing cover.
The limiting factor on most CRP acreages for upland gamebirds (especially quail) is the lack of woody (brush) cover. The habitat of most wildlife species will be improved if the area has 10 to 15 percent woody cover. Several alternatives exist for enhancing woody cover in and around CRP contracts. These alternatives include; (a) maintaining/enhancing what brush is present, (b) planting suitable species, or (c) creating artificial loafing coverts (e.g., brushpiles).
Maintaining/enhancing existing brush.
Several brush species readily invade CRP fields. Depending on the site, these may include mesquite, black willow, saltcedar, sandplum, flameleaf sumac, black locust, elm, or willow baccharis. Of these, sandplum and mesquite offer the greatest potential for developing loafing sites. Sandplum and mesquite typically become visible in CRP fields after 7-10 years. However, it may take several more years before the shrubs attain dimensions suitable for loafing coverts. Mesquite trees that are 5 to 15 years old can be enhanced by half-cutting (defined below).
When brush control on tracts adjacent to CRP fields is contemplated, try to identify sites that are important to quail. These may be mixtures of mesquite, sandplum, lotebush, hackberry, and other shrubs. If herbicides are to be used, select an individual plant treatment approach in order to minimize damage to key shrubs/sites. Mechanical control (e.g., dozing) offers a high degree of selectivity. Try to maintain or enhance the species diversity of brush present.
The most common brush surrounding CRP fields in west Texas is mesquite. Some mesquites, especially older trees, may provide adequate loafing cover as they are. Multi-stemmed mesquite can be enhanced for loafing cover by “half-cutting.” Select a tree with 8 to 12 sprouts that have smooth (not cracked) bark and that are no more than two inches in diameter at waist height. Cut into the limb only enough so that the limb can be broken over by pushing downward on it with some force. Continue until all the limbs are cut and the limbs are arranged in a wagon-wheel shape. Half-cutting doesn’t kill the limbs, and over a period of 2 to 4 years, creates a living brushpile. Hackberry trees can also be half-cut, but may sustain heavy browsing from cattle, goats, or deer.
Planting woody cover.
Before woody cover is planted, careful consideration must be given to location, size and configuration of the planting. Woody cover must be interspersed throughout the habitat. It does little good to establish woody vegetation that is not in association with food sources and other types of needed cover. Woody plant selection should be based on the wildlife species that will be managed, adaptability of the woody species and care required following planting.
The Texas Forest Service has developed “Wildlife Packets” of selected woody species for most of the wildlife species on the High Plains and Rolling Plains. Some of the better adapted species include native plum (‘Rainbow’ plum), skunkbush sumac, western sandcherry, Nanking cherry, fourwing saltbush and hackberry.
Management following planting is very important to ensure survival. The woody planting must have supplemental water, proper weed control and be protected from livestock. Supplemental water can be provided by an irrigation system, hand watering or use of “Water Harvesting” techniques. Approved chemicals, mechanical methods or weed barrier material will provide adequate weed control. If livestock are present, the plantings must be fenced. Dead woody plants should be replaced during the first two growing seasons.
Artificial structures.
Brushpiles and other artificial coverts are sometimes recommended when the above options are not feasible. Such artificial structures may include the use of brushpiles or tepee shelters. If brushpiles are used, they should be constructed about 10 to 16 inches off of the ground, using cement blocks and an appropriate frame. Brushpiles simply placed on the ground may provide cover for cottontails and skunks, but will generally not be attractive to quail. As with half-cut trees, arrange artificial coverts in clusters of five to 10 units over an area the size of a football field (about an acre).
2) Dual Wildlife and Livestock Production..
For those who desire to graze former CRP land, there are some specific management practices that may also improve wildlife habitat. Under this option, fencing and water development become a necessity. Water facilities for livestock can be modified to be of greater value to wildlife. Overflow from windmills, storage facilities and troughs should be piped or diverted a short distance away to ground level small depressions. These areas will be of greater value if grasses or forbs are protected from livestock by fencing.
Both perimeter and cross fences are needed to correctly manage livestock grazing and wildlife habitat. A minimum of 2 and preferably 3-6 separate pastures are needed to rotate livestock in a grazing system. The ability to graze some pastures heavily while others lightly is important to maximize wildlife habitat. Permanent power fences are a cost saving alternative to conventional fencing.
The stocking rate of livestock has a profound effect on the value of expired CRP land for wildlife. Heavy grazing is usually detrimental to wildlife (especially cover needs), while light to moderate use will generally favor good habitat. However, if grass build-up decreases forb growth and movement of wildlife (e.g. quail chicks), temporary heavy grazing or burning is recommended. A combination of burning and timely grazing can enhance livestock nutrition as well as wildlife habitat when managed carefully.
Disked fireguards or strips will often grow up in weeds that are valuable for wildlife food, but are not relished by livestock. Woody plantings are recommended, but will have to be fenced from livestock. Any playas or wetlands should be fenced to allow for timely grazing and resting.
3) Dual Cropland and Wildlife Habitat.
Landowners desiring to return portions of CRP grassland back to crop production may still provide some permanent cover on other portions for wildlife habitat. The most productive soils should generally be the sites converted to cropland. An approved conservation plan must be developed and implemented on these fields to maintain USDA benefits. Contact your local Soil Conservation Service office for details. Soils that are too shallow, sloping or susceptible to wind erosion should be kept in permanent cover. Key wildlife areas near creeks, brush or playas should also be retained in permanent vegetation. Leaving terraces, turnrows and field corners in grass will help create a better mix of habitat types. Reserving a portion of cropland acres for annual food plots or leaving portions of grain fields unharvested will benefit wildlife.
4) Cropland Managed for Secondary Wildlife Value.
Some landowners will desire to convert their entire CRP acreage back to crop production. An approved conservation plan must be developed for each of these fields to maintain USDA benefits.
These farmers can still carry out some specific management that will favor the use of fields by wildlife. The use of cropping sequences that include high residue and/or seed producing crops such as corn, grain sorghum, forage sorghum, pearl millet, wheat, sesame or sunflower will provide food for wildlife. Wildlife use of croplands can be increased if strips of these crops are left unharvested and standing, especially near field borders. The use of waste grain on harvested areas by wildlife can be maximized by delaying post-harvest tillage as late as possible. The use of tall growing crops (e.g. forage sorghum) or perennial grass for wind strips” will also promote use by wildlife.
Summary
Federal agriculture policies have significant effects on both the quality and quantity of our state’s natural resources, including air, groundwater, surface water, wetlands, wildlife habitat, and aesthetic beauty. Farm policy and conservation of natural resources can be mutually supportive. Permanent vegetative cover provided by the Conservation Reserve Program is a prime example of wise land use in west Texas, and is providing numerous benefits to our state.
Conservation Reserve Program lands in Texas, properly interspersed with farmed acreage, are beneficial to early successional species such as pheasants, quail, rabbits, doves, and grassland songbirds, as well as to white-tailed and mule deer. The proper use of prescribed fire is a useful grassland management too]. Woody plantings in CRP provide plant diversity within grass stands and are beneficial to quail, pheasants, and songbirds.
If more specific management assistance is desired, contact professional wildlife biologists at the Department of Range and Wildlife at Texas Tech University, local offices of the Soil Conservation Service, Texas Parks and Wildlife Department, or the Texas Agricultural Extension Service.