14 



thoroughly applied. Recent Bulletins (Nos. 154 and 157) give full par- 

 ticulars as to the ingredients and method of manufacture of this wash ; 

 it. should be applied toward the end of April or beginning of May before 

 the buds on the trees show signs of opening. One thorough application 

 will destroy almost all the scales, but a very few survivors will soon re- 

 stock a tree, as they are so extraordinarily prolific. It is necessary, there- 

 fore, to repeat the spraying year after year until none whatever are left. 

 The task is a disagreeable one, and the labor involved is expensive, but 

 it will pay in a single season through the improved quality and yield of 

 the fruit ; while its neglect simply means the speedy death and loss of the 

 entire tree. 



Fig. 23. San Jose Scale. 



The Oyster-Shell Bark-Louse (Mytilaspis ulmi), Figs. 24-26, ranks 

 next to the preceding as a destructive scale insect. It is to be found 

 everywhere throughout the Province, and inflicts an immense amount of 

 damage on apple and other fruit-trees ; it is especially abundant in old 

 and neglected orchards. Fortunately it is single-brooded, and therefore 

 does not increase very rapidly ; if it were continuously brooded, like the 

 San Jose" Scale, it would long ago have completely wiped out the apple 

 and many other fruit-trees of Ontario. It may be readily identified by its 

 peculiar shape, which resembles that of an oyster-shell, and may usually 

 be found in large numbers, sometimes completely encrusting the bark of 

 twigs and branches ; occasionally individuals even make their abode on 

 the fruit. During the winter the insect is in the egg stage and protected 



