INSECT ENEMIES 121 



damaged. Everywhere the scale is a source of ex- 

 pense and anxiety to the peach grower. 



The scale is most easily seen on the fruit, which 

 when attacked is marked with small red circles 

 around the scales. The fruit, however, is not at- 

 tacked until the tree is already pretty well infested. 

 The fruit grower must learn, therefore, to recognize 

 the presence of the scale on the twigs. Here it may 

 be seen as a rough, grayish, scurfy covering readily 

 recognized after one has become acquainted with it. 



The San Jose scale need not be mistaken for any 

 other scale insect. It is much smaller than the other 

 kinds commonly seen on fruit trees, being rather 

 smaller than a pinhead. It differs also from most 

 other scales in being distinctly circular, whereas 

 most species are oblong or oyster-shaped. It is also 

 black with a dot or pimple in the center, giving it 

 somewhat the appearance of a fungus pustule. 



The insects hibernate under these scales and be- 

 gin their activities about the time the sap starts in 

 the spring. Early in the summer the adult insects 

 emerge and the females produce their young, which 

 resemble small yellowish mites, and which move 

 about on the tree looking up fresh fields and pastures 

 new. As soon as they find suitable territory, they 

 settle down and work their beaks into the bark or 

 the young fruit and proceed to suck the juices of the 

 tree. They begin at the same time to form waxy 

 coverings which rapidly harden, turn dark colored 

 and constitute the protecting scale over them. They 

 are extremely prolific. The progeny of a few scat- 

 tering San Jose scale will infest a whole orchard 

 within a year or two. 



Fortunately this insect can be successfully held 

 in check by constant and persistent spraying. Ex- 

 perience indicates that the so-called soluble oils and 



