36 
THE SAN. JOSE SCALE. 
HABITS AND LIFE HISTORY. 
NATURE OF THE DAMAGE. 
The San Jose scale, as already stated, occurs 011 all parts of the plant, 
limbs, leaves, and fruit. As the plant becomes badly infested the 
scales lie very close together on the limbs, frequently overlapping, some- 
times with several young ones clustering over the surface of an old 
mature scale. The general appearance which they present is of a 
grayish, very slightly roughened, scurfy deposit. The natural rich red- 
dish color of the young limbs of peach, pear, and apple is quite obscured 
a. £ 
Fig. 2. — Appearance of scale on bark : a. infested twig, natural size ; 
6, bark as it appears under Land lens showing scales in various 
stages of development and young larva.'. (Original.) 
when these trees are thickly infested, and they have then every appear- 
ance of being coated with ashes. When the scales are crushed by 
scraping, a yellowish, oily liquid will appear, resulting from the mash- 
ing of the soft yellow insects beneath the scales. Examined under a 
hand lens during the summer numbers of the little orange-colored 
larvae will be seen running about, and the snowy white young scales 
will be interspersed with old brown or blackened mature scales. The 
appearance presented at this time under the lens is shown in the fron- 
tispiece and still more satisfactorily in the accompanying figure (fig. 2). 
