Miscellaneous. 435 



small branches. They may become so numerous and of such size as to 

 produce much distortion in the branches. They start with a swelling 

 of the tissue beneath the bark. This enlargement increases until the 

 bark is ruptured. The exposed surface of these knots becomes of a dark 

 olive velvety appearance. This is due to the formation of large numbers 

 of erect spore stalks which bear conidia or spores. These spread the dis- 

 ease during that season, but do not carry it over the winter. 



Late in the fall the knots lose their velvety appearance, and the 

 surface becomes black and cracked with numerous minute elevations. 

 In these elevations are borne the winter spores, which carry the disease 

 through to the next season. These knots are caused by an extensive 

 growth of the fungal mycelium in the plant. The mycelium can be 

 traced in the wood by the black streaks it forms. 



The diseased parts should be cut away and burned as soon as 

 found. Large cut surfaces should be painted. Bordeaux will protect 

 the plant from infection if the disease is prevalent in the neighborhood. 



LEAF CURL OF PEACH. 



Exoascus deformans {Burk) Fckl. 



In the spring, soon after the foliage has expanded, the peach 

 leaves become thickened and develop large blisters, which bend and dis- 

 tort them. In severe cases they may be killed and fall away, thus seri- 

 ously checking growth, and causing a loss of fruit for the season. 



The surface of these blisters become covered with a greyish bloom. 

 This is due to the formation of large numbers of upright sacs which 

 contain the spores that spread the disease. The fungus mycelium lives 

 through the winter in the buds and twigs of the affected branches, grow- 

 ing out into the new leaves in the spring. 



Most of the infections arise, however, from the spores. Bordeaux 

 should be used just before the buds open, soon after the petals fall, and 

 as soon as the first leaves become full-grown. Winter spraying against 

 ihe San Jose scale with the lime-sulphur-salt wash is a very effective 

 check. 



LEAF SPOT OR LEAF BLIGHT OF STRAWBERRY. . 



Sphaerella fragariae (Titl.) Sacc. 



This is a very common strawberry disease. It first appears as 

 round, purplish spots on the leaves. Later the interior of these tarn 

 white, leaving a purplish border. On these white areas erect tufts of 

 fungal filaments arise, which cut off numerous small summer spores, 



