254 THE POME FRUITS 



of the San Jose scale, and should learn to detect its presence 

 so that remedial measures can be adopted. The lime sul- 

 phur wash is the best-known remedy, and perhaps the most 

 effective, although kerosene emulsion as well as several 

 other oil sprays will kill the insect. The best time to spray 

 for the San Jose is in the spring, just before the buds swell. 

 Commercial lime sulphur diluted 1 gallon to 8 or 10 gallons 

 of water is the proper strength of the spray. Every part 

 of the tree should be thoroughly coated with the spray 

 material. If the infestation is very bad, spraying in the 

 fall will aid materially in reducing the damage done by 

 the insect. 



Canker Worm. The canker worm has for a long time been 

 an enemy of the apple, as well as many of the shade trees. 

 The canker worms are among the most common of the 

 loopers, or measuring worms, and they are the larvae of two 

 nearly related species of moths, very similar in both habits 

 and appearance. They defoliate the trees early in the spring. 



The two canker worms are known as the fall canker worm 

 and the spring canker worm. These insects are so named 

 because of the time at which the eggs are laid. The spring 

 worm lays its eggs in the spring, and the fall worm lays its 

 eggs in the fall. 



The worms do considerable damage in sections where they 

 occur and they seem to be very widely distributed. In fact, 

 the worms have been reported as being found in all sections 

 of the United States, except along the Atlantic coast, south 

 of New Jersey. These worms are reported to be somewhat 

 injurious in the Mississippi Valley. 



The adult of both the spring and the fall canker worm is 

 a moth. The females of both are wingless, while the males 

 of both are winged. The larvae of both species are quite 

 similar and vary from f to 1 inch in length. They are dark, 

 greenish-olive or black in color with white stripes along the 

 sides. 



The canker worms can be controlled by spraying with 2 

 pounds of arsenate of lead to 50 gallons of water, just before 

 the blossoms open and by repeating the same spray just 



