OBSERVATIONS ON FOREST TREE RUSTS 
335 
The overwintering of a fungus such as C. solidaginis on Aster and 
Solidago spp. when developing in regions so far removed from the 
alternate host Pinus as to be too remote for infection by spores carried 
by the wind is a question which has remained unanswered for some 
time. Clinton^^ refers to this problem in 1907 and comes to the con- 
clusion that the rust winters over in the rosettes principally by means 
of the urediniospores. A more recent article by Ludwig^^ gives some 
very substantial evidence leading to his belief that the uredinial stage 
of C. solidaginis on Aster, Solidago, and other hosts propagates itself 
through the winter upon the rosettes principally by means of uredinio- 
spores. He concludes that the evidence is in favor of the rusts being 
able to maintain a high degree of vigor for a long period without 
sexual reproduction. 
Office of Investigations in Forest Pathology, 
Bureau of Plant Industry, 
Missoula, Mont. 
Clinton, G. P. Heteroecious Rusts of Connecticut Having a Peridermium 
for Their Aecial Stage. Report of the Station Botanist 1907: 369. 
1^ Ludwig, C. A. Continuous Rust Propagation without Sexual Reproduction.. 
Proc. Indiana Acad. Sci. 1914: 219. 
