Competitive Graduate Student Assistantship Program

Integrated Mesquite Management for Improved Rangeland Health

Project Leaders: Erik Lehnhoff (Entomology, Plant Pathology and Weed Science,; Akasha Faist (Animal and Range Science,; David Thompson (Entomology, Plant Pathology and Weed Science,

Student: Molly Reichenborn (prospective MS student; application submitted);

Summary: Rangelands comprise a large portion of New Mexico’s 78 million acre land area, with over 26 million acres of Federal land. This land supports nearly 1.51 million beef cattle and calves and a beef industry responsible for $824 million in annual cash receipts. Furthermore, rangeland recreational activities such as hunting add $346 million annually to the state’s economy. Even with strong economic and ecological value, much of New Mexico’s rangelands have experienced degradation through a variety of disturbances. A current threat to rangeland health in New Mexico is the encroachment and infilling of honey mesquite (Prosopis glandulosa Torr.) which continues to expand its range, outcompeting and driving out native grasses, all which greatly limit rangeland ecosystem services. Mesquite control options are limited, the cost is high, and successful mesquite control coupled with a positive native plant response is never guaranteed. The purposes of this project are to improve efficacy of mesquite management and rangeland restoration by (1) investigating the integration of herbicide treatments with native biological control insects and (2) implementing novel restoration techniques to promote establishment of valuable native plants while minimizing invasion of undesirable plants. The overall goal is elevate the value of New Mexico rangelands by not only reducing mesquite, but also increasing native species for cattle grazing and for wildlife habitat.