THE PEARS OF NEW YORK III 
tion or preventive except by the most drastic sanitary measures. The 
other, pear-scab, is always present but not always destructive, although 
some varieties are always injured by it. The scab, however, is amenable 
to treatment and at its worst only destroys fruit and foliage, seldom endan- 
gering the life of the tree. The four or five other diseases of the pear in 
New York are of minor importance and are readily controlled by the treat- 
ment necessary to keep in check the scab-fungus. Pear-blight merits 
attention first. , 
Pear-blight is a malignant bacterial disease, very contagious, usually 
virulent and so terrible in its consequences as to warrant the common name 
fire-blight. No part of the tree is exempt from destruction by the malign 
bacterium that causes blight of the pear. Root, trunk, branch, leaf, flower, 
and fruit are all attacked, turn black and wither under the disease. Few 
plant diseases produce more disastrous results. The pear competes with 
the apple in importance in Europe where blight is unknown. In America 
it is a poor fourth to the apple, peach, and plum, and takes fourth place 
instead of second because of the ravages of blight. About the most impor- 
tant discovery to be made in pomology is a race of blight-resistant pears. 
Failing in this, if the pear-industry is to grow, or even continue in its present 
magnitude, blight-resistant stocks must be found. 
The symptoms of pear-blight are so characteristic that the disease 
cannot be confounded with any other malady or condition of the tree. 
It appears earliest in the season on the blossoms causing blossom-blight. 
Attacked by blight, the blossoms wilt, and after the petals fall, fruit and 
spur show the characteristic blackening of the disease. Blossom-blight 
may escape the attention of the pear-grower, but twig-blight, a succeed- 
ing form of the disease, can escape no one who has the sense of sight. No 
other disease of the pear brings on such palpable destruction to the tree 
as twig-blight. No other disease causes such comfortless despair to the 
grower. Twig, branch, or tree, as the case may be, in all affected parts, 
turns black, the leaves droop, seeming to show the effects of fire. A marked 
symptom is, if there can be doubt of those given, that the blackened foliage 
clings most tenaciously to the dead branches. Twig-blight is the most 
common manifestation of the disease. Another form of the blight appears 
as a canker on the trunk and large branches — canker-blight or body- 
blight. These cankers are dark, smooth, and sunken, with definite margins 
marked by a crevasse in the winter; but as spring comes on the advancing 
margins become raised and more or less indefinite. Occasionally an opaque 
