Mesquite Tree and Grassland (IMAGE) University of Arizona Caption Their extremely deep-reaching roots give mesquite trees an edge over grasses. Credit Greg Barron-Gafford Usage Restrictions This visual may only be used in conjunction with reporting/posting of this news release. Image/video credit must be included exactly as indicated. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.