24 CONTROL OF THE CHESTNUT BARK DISEASE. 
disease spreads primarily in the inner bark and produces character- 
istic lesions which girdle the tree at the point attacked. 
(4) Conspicuous symptoms are the development of bunches of 
sprouts below the girdling lesions; the half-formed yellowish leaves 
in the spring on the previously girdled branches; the reddish-brown 
leaves on branches girdled in summer, and the yellow, orange, or 
reddish-brown pustules of the fruiting fungus on the bark. It is 
practically useless to attempt systematic location of the disease from 
October to April, inclusive. 
(5) The spores may be carried considerable distances on chestnut 
nursery stock, tan bark, and unbarked timber; also by birds, insects, 
squirrels, etc., which have come in contact with the sticky spore 
masses. Water quickly dissolves these spore masses and the minute 
spores are in this way carried along -with water, as, for instance, with 
rain water running down a tree. Borers’ tunnels form the most 
common places of entrance for spores. , 
(6) The only known practical way of controlling the disease in 
a forest is to locate and destroy the advance infections as soon as 
possible after they appear and, if the disease is well established near 
by, to separate the area of complete infection from the comparatively 
uninfected area by an immune zone. Advance infections should be 
located by trained observers and destroyed by cutting and burning. 
As the disease develops almost entirely in the bark, this must be com- 
pletely destroyed (burned). 
(7) In order to carry out the above methods it is essential that 
the several States concerned secure necessary legislation and appro- 
priations, following the example of Pennsylvania, as no law exists 
whereby the Federal Government can undertake such work and 
cooperation among private owners without State supervision is 
impracticable. 
(8) Chestnut nursery stock should be rigidly inspected for the 
disease and only perfectly healthy plants passed. 
(9) The life of valuable ornamental trees may be greatly pro- 
longed by promptly cutting out all diseased areas and removing all 
disease-girdled branches and then covering the cuts with tar. Spray- 
ing is of no use in stopping the fungus after it has once started 
growth in the bark. j 
(10) It is recommended that owners of infected woodland cut 
down and utilize the diseased chestnut timber as soon as possible. 
(11) For the present the planting of chestnuts anywhere east of 
Ohio is not advised, but there is no apparent reason why chestnut 
orchards west of Ohio may not be kept free from the disease. 
[A list giving the titles of all Farmers’ Bulletins available for distribution 
will be sent free upon application to a Member of Congress or the Secretary of 
Agriculture. ] 
407 
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