PREVENTION AND CURB. 69 
planting; the other 20 were planted without removing the galls, 
after dipping in Bordeaux mixture. After two seasons of growth, 
in which none of the trees died, no result from the treatment was 
obtained, as all of the trees still showed the disease. 
Clinton (8) reports as follows from Connecticut: 
In 1899 Doctor Sturgis set out on the station grounds ten young trees affected with 
knots; part of these had the knots cut off, others had knots cut off and roots then 
treated with copper sulphate, and some were left with knots on. After three seasons 
of growth these trees were dug by the writer and the roots carefully examined. Very 
little difference could be seen in any of the trees at this time, and the knots had 
spread very little, if any. 
Norton (37) says: ‘Apple trees slightly affected, often apparently 
recover and make good trees, but even then the life of the tree may 
be cut short and the ground infected.” 
Garman (15) advocates the removal of the diseased parts with a 
knife, but does not consider this treatment satisfactory, as it is 
kas to weaken the tree. 
Alwood (2), experimenting with seven trees, from which he cut 
off the galls, giving the trees a subsequent treatment with strong 
Bordeaux mixture, found that several of them showed a characteristic 
erowth of crown-gall; two made a more normal growth. 
Recommendations for the treatment of the disease in orchards.—The 
question as to whether it is advisable to remove the galls from trees 
in an orchard depends, first, upon whether the presence of the gall in 
itself is of greater injury to the tree than the effect of the wound re- 
sulting from its removal combined with that of the antiseptics used 
for treating the wound; and, second, upon the danger of the disease 
spreading to other trees. In an apple orchard, from the results of 
the writer’s experiments, it appears that there is no danger of a 
serious spread of this disease to other apple trees. 
There is very good reason to conclude from the writer’s experi- 
ments and studies that small knots, swellings, or tufts of roots on 
orchard trees have no effect on their growth. Where these knots, 
etc., can be removed without serious injury to the tree, it may be 
best to remove them. Knots or stem tumors on the outer limbs or 
twigs may be removed when they first appear. In cases where there 
are small growths, galls, or woolly-knot, on the trunks or roots of 
large, valuable trees (Pl. IX, fig. 1), it will not pay to mjure the 
trunk of the tree by their removal. 
Howard’s experiments, previously cited, prove the futility of 
cutting crown-galls from the young apple trees and treating them 
with antiseptics. The trees used in his experiments, if they had not 
been treated, might be alive and bearing to-day. 
Ina pall experiment with seedling trees, the writer cut off the 
soft galls from a number of yearling cepillines and planted the seed- 
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