PEACH DISEASES 321 
ward, being found in North Carolina, Virginia, West Virginia 
and Arkansas. It also occurs, but rarely, in the state of Ohio. 
The disease is not usually serious, although it prevails to a very 
noticeable extent in damp, shaded localities on trees bearing 
dense foliage. It was unusually prevalent on the Delaware 
and Chesapeake peninsula in the fall of 1891. Pale, yellowish 
or olivaceous spots with definite margins are produced by the 
fungus Cercosporella Persice on the upper surface of the leaves ; 
on the lower surface, opposite the yellowish spots, will be 
found a delicate frost-like growth of the fungus—the conid- 
iophores. 
Little is known of the causal fungus and its control. 
REFERENCES 
Thaxter, R. Miscellaneous notes. Cercosporella Persice Sacc. 
Connecticut Agr. Exp, Sta. Rept. 1889: 173. 1890. 
Smith, E. F. Field notes, 1891. Frosty mildew. Journ. Myce. 7: 
91-92. 1892. 
STEM-CANKER 
Caused by Phoma Persice Sacce. 
In 1896 a peculiar stem-trouble was noted in Ohio affecting 
primarily nursery-stock and the twigs of older orchard trees. 
Two years later it was described, and was called constriction 
disease, or stem-blight. It has subsequently been reported 
from Connecticut and New York on seedling peaches. The 
affected twigs are partially or completely girdled by a cankerous 
formation. The parts above the lesion do not die immediately, 
but eventually they succumb, as evidenced by a yellowing and 
a premature defoliation. Just above the canker a swelling 
of the stem occurs, resulting in a constricted appearance. Scat- 
tered over the canker will be found numerous pycnidia of the 
fungus which show as black specks. The pathogene develops 
Y 
