Figure 4 . - - Limb rust can 

 markedly reduce the 

 beauty of pine stands, 

 as in this example in 

 Bryce Canyon National 

 Park. 



Although Umb rust outbreaks are widely spaced in time and although local changes in intensity can 

 appear abruptly (18), it seems likely that limb rust maintains a fairly constant population over its whole 

 distribution area. At least there is no good evidence substantiating an overall increase in the rust; no large 

 concentrations of young infections have been reported recently. If future outbreaks are identified early, 

 serious damage can be avoided where silvicultural practices can be used. 



LITERATURE CITED 



1. Arthur, J. C. 



1929. The plant rusts (Uredinales) . New York: John Wiley & Sons, Inc. 446 pp. 



2. Buchanan, H. 



1960. The plant ecology of Bryce Canyon National Park. Doctoral diss. , Univ. Utah. 136 pp. 



3. California Forest Pest Control Action Council. 



1959. Forest pest conditions in California- -1958. Sacramento: CaUf. Div. Forest. 29 pp. 



4. 



1965. Forest pest conditions in California- -1964. Sacramento: Calif. Div. Forest. 20 pp. 



5. Garrett, A, O. 



1921. Smuts and rust of Utah--IV. Mycologia 13: 101-110. 



6. Graham, S. A., and F. B. Knight. 



1965. Principles of forest entomology. 4th ed. New York: McGraw-Hill Book Co. 417 pp. 



7. Hedgcock, G. G. 



1912. Notes on some western Uredineae which attack forest trees. Mycologia 4: 141-147. 



8. 



1913. Notes on some western Uredineae which attack forest trees. II. Phytopathology 3: 15- 17 . 



9 



