THE AUTHORS 



RALPH C. HOLMGREN is a Range Scientist at the Provo, 

 Utah, Unit of the Intermountain Forest and Range 

 Experiment Station. He has a bachelor of science 

 degree from Brigham Young University, and worked 

 on game range rehabilitation research before being 

 assigned to desert ecology in Nevada and Utah 13 

 years ago. 



SAM F. BREWSTER, JR., was a Research Technician with 

 Intermountain Station at the time the study reported 

 here was started. His participation in the study 

 continued after he became a graduate research as- 

 sistant in the Botany Department of Brigham Young 

 University, where he received a Ph. D. degree in 

 1970. He is now Instructor of Biology, Ricks Col- 

 lege, Rexburg, Idaho. 



