THE UREDINALES OF OREGON! 
HH. S. JACKSON 
Purdue University 
Since no account of the rusts of any of the states bordering on the 
Pacific coast is available for reference by the students of the flora of 
that region, it has seemed desirable to bring together in the form of 
an annotated list the results of a study of the species occurring in 
Oregon, which has extended, intermittently, over a period of eight 
years. 
The account is the result of a study begun by the author in 1909 
at the Oregon Agricultural College and finally prepared in the form 
here presented at the Purdue University Agricultural Experiment 
Station. 
On account of the great diversity of conditions the State of Oregon 
presents a wonderful field for work in any phase of botanical study. 
The area of the State is approximately 96,000 square miles, an area 
considerably greater than that included in all the New England states 
combined. The great range of climatic and topographical features 
existing in the State offers favorable conditions for the development 
of a flora not only large in number of species, but very diverse in char- 
acter. Within the confines of the State is to be found a range in alti- 
tude from sea level to perpetually snow-capped mountains. The 
annual rainfall varies from over 80 inches in some localities to below 
10 inches in others, resulting in the development of a flora almost 
tropical in its luxuriance on the one hand, and one having many of 
the characteristics of a desert on the other. 
The diversity of the Phanerogamic flora which has developed 
under these conditions offers an especially attractive field for the 
student of the parasitic fungi. Many species of all groups are to be 
found especially in those portions of the State having a heavy annual 
rainfall. 
Rusts are found in great profusion in all sections of the State. 
The first collections of this group made by the writer were accumu- 
lated in connection with an effort to obtain general material for class 
use. The greater part of the collections have been made in connection 
with local excursions, the primary object of which was recreation. 
1Contribution from the Botanical Department of Purdue University Agri- 
cultural Experiment Station. 
198 
