INSECT AND FUNGOUS ENEMIES OF THE APPLE. 31 
On the young spots the fungus growing underneath produces small 
black receptacles in which spores are borne. These spores, when dis- 
charged, may infect other fruits, leaves, and twigs. 
INFECTION PERIOD. 
The fungus in the twig cankers becomes active about the time the 
apple trees bloom, and about four weeks later fresh spores are pro- 
duced, ready to infect the fruit and leaves. If the weather conditions 
are favorable, infections, therefore, begin to take place from four to 
five weeks after the petals fall. Infections may continue to take place 
for several weeks, but as a rule the chief damage to the fruit crop 
results from the infections occurring within six weeks after the petals 
fall. Spraying for its control should, therefore, be done in time to 
protect the fruit from these early infections. The fungus is a slow 
grower and the spots may not show up until two or three weeks have 
elapsed after infections have taken place, so that to begin spraying 
when the first spots appear would be much too late to prevent the 
disease. 
TREATMENT. 
Unfortunately the lme-sulphur sprays have not proved entirely 
satisfactory for the control of apple blotch. In orchards where the 
disease is not very serious lime-sulphur solution may be used with 
good results, but for the present at least the chief reliance for the 
prevention of the disease should be placed on Bordeaux mixture. 
Lime-sulphur solution should be used with the first codling-moth 
spray as soon as the petals fall, thus avoiding a part of the danger 
of spray russet, and Bordeaux mixture should be used in the subse- 
quent applications. The spraying schedule for bad cases of apple 
blotch should be about as follows: (1) Lime-sulphur solution as soon 
as the petals fall; (2) Bordeaux mixture three weeks later; (3) Bor- 
deaux mixture six weeks after the petals fall; and (4) Bordeaux 
miture nine weeks after the petals fall: In a dry season the third 
treatment may be omitted, and in mild cases lime-sulphur solution 
may be used in all the applications. For the control of the codling 
moth and curculio, arsenate of lead should be added to the first, 
second, and fourth treatments. 
CEDAR RUST. 
Cedar rust, also known as orange rust, is a disease affecting both 
fruit and foliage of the apple, quince, and other pomaceous plants. 
It is common in practicaly all the apple-growing districts east of 
the Rocky Mountains, causing considerable damage to certain varie- 
ties of apples. In some sections the disease is troublesome nearly 
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