Rangeland Shrub Research

Ecology, Management and Biomass Utilization

LINKS

Ansley Publications by Subject

Integrated Ranch Management Research at Vernon 

Texas A&M Ecosystem Science and Management Department

TEXNAT Natural Resource Management Site

Fire Effects on Plants U.S. Database

INTRODUCTION

The encroachment of woody plants (i.e., "brush") on grasslands and rangelands is a worldwide phenomenon.  Woody plants can reduce forage production for livestock, increase erosion potential by reducing herbaceous cover, and potentially decrease off-site water yield for urban consumption.  In contrast, moderate densities of woody plants as a "savanna" can offer some benefits through enhanced wildlife habitat, soil nutrient additions, and stimulating herbaceous species diversity.  Technology is needed to better understand these interactions and offer woody plant management solutions.  A new option may include the utilization of woody shrub biomass for energy purposes.

The semi-arid environment of the Rolling Plains in North Texas is an ideal field laboratory for investigating the woody encroachment problem because of the high level of woody encroachment and the economic significance of rangelands to the region.  The most dominant woody species are honey mesquite (Prosopis glandulosa) and redberry juniper (Juniperus pinchotii).  Prickly pear cactus (Opuntia spp.) is also a significant problem and management solutions to limit its invasion are needed.

RESEARCH PROJECTS

We are conducting shrub ecology studies that measure rates of mesquite and juniper encroachment, shrub effects on herbaceous production, mesquite water use and mesquite seed ecology. 

Our research includes quantifying effects of woody plant management treatments such as prescribed fire and herbicides on target and non-target species and measuring rates of ecosystem restoration.

The mesquite savanna project integrates use of fire and herbicides to convert thickets of mature mesquite to savannas to enhance ecosystem diversity and multiple use options.

Recently, a shrub biomass to bioenergy research project was initiated to investigate the potential of rangeland woody plants such as mesquite for bioenergy purposes such as ethanol or bioheat.

Summer fire in a stand of mesquite

Mesquite seedling emerging from a deer pellet

Mesquite harvesting machine

Photos by J. Ansley