1. Department of Natural Resource Ecology and Management; Oklahoma State University; 008C Agricultural Hall; Stillwater; OK; 74078; USA
2. Texas A&M Agrilife Research Center; Texas A&M University; P.O. Box 918; Sonora; TX; 76950; USA
3. Department of Ecosystem Science and Management; Texas A&M University; 2138 TAMU; College Station; TX; 77843; USA