DISEASES OF THE QUINCE, 85 
The bacterial theory seems to account for all the 
phenomena connected with this disease. The bacteria 
found in the disease will produce it from inoculation in 
about a week; and by the second week the stem and 
leaves of the twig will be dead, and by the third week 
the disease will be extended down the limb, marking its 
progress by the brown bark and blackened leaves peculiar 
to the blight. 
Bacteria may enter through the flowers as well as the 
tender tissues of the growing twigs, or any opening in 
the older bark of the trunk and limbs. No visible effect 
is likely to be seen for several weeks. In June, and on- 
ward for a number of months, it may be seen as branch 
after branch reveals its presence. It grows very slowly 
in cold weather, and rapidly in warm and moist weather. 
I have found the annual salting of both quince and 
pear trees, when done before the spring growth begins, 
to operate as a preventive; but can not say there will 
be none in the future. Later salting has not always pre- 
vented it. When the disease is manifest, no time should 
be lost in removing and burning the diseased portions. 
Be sure to cut far enough below the affected parts to re- 
move all the disease. 
So long as there remains any portion of the trunk or 
branches not encircled with the blight, the tree may re- 
cover. I have trees that have done good service for 
several years, which were all destroyed except a strip on 
one side. The diseased parts were cut away, splitting off 
the blighted wood from one side of the trunk, and the 
rest has grown well, now nearly covering the split portion. 
Accepting the bacterial theory of the disease, we might 
propose to control it by spraying the trees with some 
antiseptic ; but in practice the best thing we can do is 
to prevent it as far as possible, and diligently destroy 
every trace of the disease. 
The microscope shows that both leaves and fruit are 
