INJURIOUS AND BENEFICIAL INSECTS OP CALIFORNIA. 



157 



Nature of Work.— The males and females work upon the branches, 

 small twigs and leaves. 



Distribution. — This scale occurs in many foreign citrus growing- 

 regions and is often taken in quarantine. It has been reported from 

 San Diego County, but has evidently never become thoroughly estab- 

 lished anywhere in the State. 



Food Plants. — The favorite food plant is the orange, though other 

 species of citrus trees are attacked as well as Euonymns, Osmanthus 

 ilicifolius and palms. 



Control. — Fumigation as for the red scale or the purple scale will 

 easily control this pest. 



THE EUONYMUS SCALE 



Chionaspis euonymi Comstock 



(Fig. 135) 



Description.— The female scale is dirty-brown or nearly black with 

 3 r ellow exuvia, convex, elongated, broader posteriorly and from ^ to 

 1-11 inch long. The scale of the male is 

 snow-white, very narrow, slightly shorter 

 than the diameter of the female scale 

 and strongly tricarinated. 



Life History. — The young insects are 

 yellow and soon settle to produce the 

 scales of the male or female. So thick 

 are they that plants are sometimes 

 ruined by the females, while the same 

 may appear to be covered with fine 

 flakes of snow, due to the great numbers 

 of the minute white scales of the males. 

 The insect attacks all parts of the host 

 and is very destructive, often completely 

 killing entire hedges. 



Nature of Work. — The males and 

 females may be found upon all parts of 

 the infested plants, often so thick as to 

 overlap and completely hide the twigs. 



Distribution. — In California it occurs 

 in greenhouses or is simply taken in 

 quarantine. 



Food Plants.— Euonymns latifolius, E. 

 japonicns, E. europceus, E. airopurpurcus, Celastrus scandens and 

 orange are the recorded food plants. 



Control.— To control this pest spray with kerosene or distillate 

 emulsion or resin wash every two weeks during the months of May 

 and June, or until the scale has disappeared. The work should be done 

 during the hatching period and care taken to see that the sprays are 

 not strong enough to injure the foliage. 



In the winter, when the plants are dormant, much stronger solutions 

 of the same sprays or lime-sulphur (1-13) m&y be used with lasting 

 effects. 



Fig. 135. — The euonymus scale, 

 Chionaspis euonymi Comst., on leaf 

 of Euonymus. Natural size. (Orig- 

 inal ) 



