FOES AND FRIENDS OF THE PLANT 



217 



Red scale. The red scale of the 

 orange, which does great damage in 

 Florida and other places where 

 oranges are grown, has now spread all 

 over California. 



Scale of the palm. This is de- 

 scribed in Bulletin 56 of the Arizona 

 Experiment Station. 



Parasites of scale insects. By 

 keeping leaves covered with scale in- 

 sects in tumblers, we shall be able to 

 see the tiny wasps, not much bigger 

 than a pin head, which are parasites 

 on the scale insects. They lay their 

 eggs in the scale insects, and the 

 young wasps feed on their bodies. 

 After a time they come out as tiny 

 winged wasps. The tumblers should 

 be covered with cloth to prevent 

 them from escaping. 



THE VINE HOPPER 



This is a small insect, not more 

 than a tenth of an inch long, of 

 a pale yellow color, with irregular 

 red markings. They are usually 

 found on the underside of the leaves. 



The insects pass the winter feeding on various plants, 

 and if the weather is severe, they are largely killed 

 off. They lay eggs during the spring and throughout 



FIG. 124. Black scale on 

 lemon. (Enlarged.) 



