428 MANUAL OF FRUIT DISEASES 
The spores produced in great abundance from the spore 
stalks on diseased fruits are scattered through the berry patch 
or field, and many fruits become inoculated. When moisture 
is abundant and retained on the plants through the day, the 
spores readily germinate. Whether the germtubes can pene- 
trate the uninjured surface of fruits is not certain, though this 
is probable. The mycelium spreads rapidly and profusely 
throughout the tissues of the fruit, between and through the 
cells, which are rapidly killed. The fungus feeds upon the 
substance of the invaded tissues and soon sends forth great 
numbers of brown stalks, branched at the tips and bearing 
thereon many grape-like bunches of oval thin-walled spores. 
These spores are readily scattered by the wind and cause new 
infections. How this fungus winters is not certain, though 
probably by means of sclerotia. Sclerotia are black tuber-like 
bodies of densely interwoven mycelium which are formed 
by all species of Botrytis, in dead host-débris. They pass 
the winter in a dormant condition, and germinate the following 
spring, producing tufts of spore stalks bearing spores like those 
already described. These spores initiate new infections. 
Control. 
Little definite information based upon experimental data 
or experience can be offered. Losses in shipment may be re- 
duced by careful sorting out of all diseased or injured berries. 
Discarded fruit should not be allowed to accumulate about the 
packing house, but should be burned or buried daily. Field 
losses will be much reduced by growing the plants well apart 
in order to afford a maximum of light and air. 
REFERENCES 
Stevens, F. L. A destructive strawberry disease. Science n. s. 
39: 949-950. 1914. 
Stevens, N. E. Pathological histology of strawberries affected by 
species of Botrytis and Rhizopus. Jour. Agr. Res. 6: 361-366. 
1916. : 
