INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 161 



THE PINE-LEAF SCALE 



Chiondspis pinifolice (Fitch) 

 (Aspidiotus pinifolice Fitch) 



(Fig. 139) 



Description. — The scales of the mature females are white, narrow, 

 pvrif'orm or elongated, the shape being' elongated and narrow if on 

 a narrow-leaved pine and pyriform if on a wide-leaved host as the 

 mountain nutmeg (Torreya calif 'arnica) . They average about -} inch 

 in length. The exuviae are light yellow. The male scales are very 

 narrow, half as large as the females, and pure white with yellow 

 exuviae. The eggs are elongate, very small and white. 



Life History. — The winter is passed in the egg-stage under the 

 female scales. The eggs hatch in the spring and the young of the 

 first brood are mature by midsummer. There are two broods a year. 



Nature of Work. — This scale works only upon the needles of con- 

 iferous trees and is often so abundant as to cause the foliage to turn 

 yellow and the tree to assume a sickly appearance. 



Distribution. — The pine-leaf scale is very common throughout the 

 entire State, occurring in the wild mountain regions as well as in the 

 valleys. 



Food Plants. — Many of the coniferous trees are attacked including 

 the Bohtan, Corsiean. digger, Monterey, red. Scotch, Soledad, sugar, 

 Swiss stone, yellow and white pines. Pin its torreyana, fir, California 

 nutmeg and spruce. 



Control. — Spraying with kerosene or crude oil emulsions is recom- 

 mended for ornamental trees. 



Natural Enemies.— The two-stabbed ladybird beetle {Chilocorus 

 bivulnerus Muls.) and other species of ladybird beetles prey upon this 

 scale. 



11—13664 



