160 



INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 



Distribution. — This species seems to be limited to the southern part 

 of the State, having been reported only from San Bernardino, River- 

 side. Los Angeles and Ventura counties. 



Food Plants. — The willow is the normal food plant of this scale, 

 but it also attacks butternut, cotton wood, honey-locust and poplar. 



Fig. 138. —The cottonwood scale, Chionaspis ortholobis 

 Comst, on willow. Enlarged twice. (Original) 



Control. — Control measures are the same as for the pine-leaf scale 

 ( Chionaspis pinifolice) . 



Natural Enemies.— The two-stabbed ladybird beetle has been noted 

 as preying upon this scale. 



