The Beaver Dam Wash NCA is within an ecological transition zone between the Mojave Desert and the Great Basin. Creosote bush, white bursage, and other desert shrubs grow at lower elevations and provide habitat for desert bighorn sheep and the Mojave Desert tortoise, a threatened species listed under the Endangered Species Act. Joshua trees and dense stands of blackbrush cover the slopes of the Beaver Dam Mountains, which rise along the eastern boundary of the NCA. Surface water flows in the upper reaches of Beaver Dam Wash, but rarely travels all the way through the NCA. Riparian vegetation along the stream channel is important habitat for migratory birds and other wildlife. Many large and destructive wildfires have burned within the Beaver Dam Wash National Conservation Area (NCA) Historically, wildfires of this size and severity were rare; however, repeated fire activity and the expansion of cheatgrass across the are have altered historic fire regimes. These changes have resulted in more frequent and higher severity wildfires, which have caused significant mortality of Joshua trees, a species poorly adapted to repeated fire. Continued fire occurrence threatens remaining Joshua tree stands and associated habitats that have not yet been impacted by wildfires. Implementation of an herbicide treatment to reduce cheatgrass is necessary to break the invasive grass-fire cycle, lower wildfire risk and protect remaining Joshua tree population for future fire related mortality.

The objectives of this project are to treat areas within the NCA where cheatgrass has displaced native plant communities and to prioritize locations with a higher-than-average risk of wildfire ignition and spread within the NCA. In addition, the project would implement an Integrated Weed Management Plan (IWMP) across the NCA, utilizing appropriate methodologies to control and where feasible, eradicate noxious weed and other exotic invasive species.

The Beaver Dam Wash National Conservation Area (NCA) is designated as critical habitat for desert tortoise. The Mojave desert tortoise is listed as a threatened species in the United States, and its long-term persistence continues to be challenged by wildfires. The Beaver Dam Wash NCA encompasses approximately 72,031 acres, of which an estimated 38,138 acres-more than 50 percent of the NCA-have been affected by wildfires. These wildfire events have facilitated the spread of non-native annual grasses across the landscape, increasing fine fuel loads and altering the natural fire regime of this desert ecosystem. The proliferation of invasive annual greases, coupled with increased visitation and recreational uses within the NCA over time, has further elevated the risk of recurring wildfires in areas that are still recovering from previous fire disturbances.

The Beaver Dam Wash NCA Fuel Break Project is in conformance with the management goals, objectives and action decisions from the Integrated Weed Management Plan For The Control And Eradication Of Noxious And Invasive Species And Programmatic Environmental Assessment (December 2022)

Numerous wildfires have occurred throughout the Beaver Dam Wash national Conservation Area (NCA), resulting in substantial changes to vegetation communities. In many locations, native plant communities have been replaced or heavily influenced by invasive species such as cheatgrass, which are more susceptible to ignition and promote increased fire frequency. Areas that historically experienced infrequent low severity fire are now prone to more frequent and higher severity wildfires. Additionally, increased visitation and recreational use over time have elevated the risk of human caused fire ignitions across the NCA. Fine Fuels such as annual grasses-especially invasive species like red brome and cheatgrass have increased fuel continuity across the landscape, raising the likelihood of ignition and the potential for larger, more frequent wildfires. In riparian and wash-bottoms areas, dense vegetation can contribute to higher fuel loads and increased fire intensity, which may negatively affect soil stability, native plant communities, and wildlife habitat. Wildfire in this setting had the potential to alter vegetation composition, promote further invasive species expansion, and increase erosion and sediment transport within the wash. As a result, fuels management and fire planning within the Beaver Dam Wash NCA are important for reducing wildfire risk, protecting ecological values and maintaining watershed function.

Cheatgrass competes strongly with native plants for shallow water resources during the spring, a crucial time in seedling establishment (Cline et al. 1977; Booth et al. 2003a). Reduced water availability negatively impacts the survival and growth of transplanted native species (Link et al. 1990). This project would increase water availability for native transplanted and seeded species by reducing the competitive cheatgrass.

All necessary and required clearances will be completed prior to project implementation. Compliance to herbicide use and handling instructions will be adhered to by all involved in the aerial application process.

Herbicide would be aerially applied. Aerial seeding and hand planting may occur after the herbicide application.

Short and long term monitoring of treatment areas and evaluations of the efficacy of the treatment. Monitoring will be conducted and treatment of weed infestations be continued as needed for a minimum of 5 years or until the target species is eradicated. The goals of monitoring would be to determine whether infestations treatment methods have proved to be the most effective and cost efficient, while creating the fewest negative environmental impacts, for a specific noxious weed or invasive species.

This project will be implemented by the Bureau of Land Management in cooperation with the Utah Division of Wildlife and Forestry Fire and State Lands.

Adaptive management would be applied, and post monitoring would aid future management decisions. Second phase of this treatment would be applying native seeds aerially and handplanting native seedlings.

Beaver Dam Wash NCA is located in the southwestern corner of Washington County, Utah, along the state lines of Nevada and Arizona. The landscape provides an interesting ecological transition zone between the Mojave Desert and the Great Basin. The warm, dry climate of the NCA allows for enjoyable outdoor activities during all but the hot summer months. It is an increasingly popular destination for camping, hiking, hunting, bird watching, mountain biking, and off-highway vehicle riding on a network of unpaved roads. Tent and RV campers enjoy 38 designated dispersed campsites with fire-rings, all located along maintained backcountry routes. The NCA provides opportunities for world class rock climbing at Welcome Springs, Bulldog Knolls, and Woodbury Crags. Over 70 climbs, ranging in difficulty from 5.7 to 5.14, are easily accessible via short hikes from the Mojave Desert Joshua Tree Road Scenic Backway in the NCA. Many of the 40 Special Recreation Permit (SRP) holders who operate in the NCA offer commercial guiding services for rock climbing, mountain biking, and hunting for desert bighorn sheep and mule deer. This project will help protect the area that visitors have come to love.