ACKNOWLEDGMENTS 



Forest Service research on limb rust has been encouraged 

 and supported by the National Park Service, U.S. Department 

 of the Interior. Personnel of the Park Service and of two 

 branches of the Forest Service- -the Intermountain Station and 

 Region 4 --took part in the pest sunrvey reported herein. Obser- 

 vations in Mexico were made in collaboration with the Instituto 

 Nacional de Investigaciones Forestales of the Mexican govern- 

 ment and also with the Rocky Mountain Forest and Range 

 Experiment Station of the Forest Service. 



Research on limb rust builds on the foundation laid by J. L. 

 Mielke, Forest Service (retired). Figures 1 and 3 are from 

 his photographs. 



