298 Gardening 
may be present. It will not destroy the fungus after it 
has gained entrance to the inside of the leaf, however. 
Spraying with Bordeaux mixture can therefore only 
prevent the appearance and spread of the disease; it 
cannot cure diseased plants. Cucumber growers who 
plant on a large acreage do not wait for the disease 
caused by downy mildew to appear, but spray about 
seven times during the growing of the crop. The home 
gardener should at least begin spraying as soon as he de- 
tects signs of disease. If, however, the disease has been 
present in previous years or is known to be in the lo- 
cality, it is advisable to begin spraying as soon as the 
cucumber plants are well above the ground, and to. 
spray thereafter at intervals of about 10 days. Ifrains 
occur soon after spraying, much of the poison will be 
washed from the leaves; it will then be necessary to 
spray again immediately. 
LEAF BLIGHT OR LEAF SPOT OF THE TOMATO 
It is estimated by the United States Department of 
Agriculture that the tomato-leaf blight causes a loss to 
tomato growers in the United States of at least $5,000,000 
each year; yet this loss could largely be prevented if the 
growers would learn to recognize the symptoms of the 
disease and to spray properly with Bordeaux mixture. 
The fungus which causes this disease attacks the lower 
leaves first. Small angular or circular spots appear, 
having grayish or light-colored centers and dark-colored 
borders. These spots are seldom more than ¢ inch in 
diameter. Leaves thus attacked curl, and then dry and 
fall. As the disease continues to extend to the newer 
