A Grazing Texas Longhorn (image) Arizona State University Caption An increase in tree and shrub cover on grasslands in the US and Argentina leads to a 2 percent loss in livestock production. Credit John and Karen Hollingsworth, U.S. Fish and Wildlife Service Usage Restrictions with photo credit 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.