344 ‘MANUAL OF FRUIT DISEASES 
and are considerably larger and lighter colored than the pycnia. 
Within the ecia are developed xciospores which blow to and 
‘infect the red cedar. These spores may carry for a consider- 
able distance. Cedar-apples are produced on the cedar as a 
result of seciospore infection. These cedar-apples are merely 
irregular, globoid galls measuring an inch or less in diameter. 
Their appearance has given rise to the popular term cedar- 
apples. The fungus mycelium developed from the eciospores 
grows within the tissues of the red cedar, stimulating them to 
over-growth, whence the gall. From the surface of the gall 
arise numerous short, beak-like horns which are composed of 
another kind of rust spores — the teliospores. In this rust 
fungus these spores may be produced year after year for several 
seasons from the same gall. When moist the beak-like horns 
become gelatinous and assume a bright orange color. In this 
gelatinous mass the teliospores grow out and produce a number 
of smaller spores called sporidia. This takes place in the 
spring. These sporidia are blown to the pear, apple or other 
host, where infection results. 
Control. 
Spraying for pear-rust is of little or doubtful value. Since 
the red cedar harbors the fungus, and since the fungus requires 
the presénce of this plant in order to perpetuate itself, it is 
logical to destroy all red cedars within a reasonable distance. 
In the case of apple-rust the distance is put at one mile (see 
page 70), within which radius all cedar trees should be eradi- 
cated. 
REFERENCES 
Pammel, L. H. The cedar apple fungi and apple rust inIowa. Gym- 
nosporangium globosum. Iowa Agr. Exp. Sta. Bul. 84: 10-16. 
1905. 
Thaxter, R. Miscellaneous notes. Rust of pears. Connecticut 
‘Agr. Exp. Sta. Rept. 1890:98. 1891. 
Stewart, F.C. Notes on New York plant diseases, I. Pear. Rust, 
Gymnosporangium globosum Farl. New York (Geneva) Agr. 
Exp. Sta. Bul. 328 : 376-377. “1910. ! 
