DISEASES AND INSECT PESTS 221 



each containing a white grub. These grubs, after feed- 

 ing for a time, become pupae, and finally emerge as the 

 black, four-winged fly, Rhodites rosce. 



Other galls, much different in appearance, may be 

 noticed on the leaves and green shoots. Some are 

 smooth, pea-like swellings ; others are covered with 

 hairs or bristles, and some may be irregular blisters 

 appearing on the leaves ; all contain a tiny larva, thriv- 

 ing on the tissues and sap of the bush. The small gnat, 

 Cecidomyia toscb, is the most common of these pests. 



Remedies. — Insecticides keep the flies off the bushes, 

 but as the galls are scarcely ever very numerous, they 

 should be removed and burned whenever noticed. 



Beetles and Chafers. — Beetles may gnaw inside 

 the buds and destroy the blooms. An active little pest 

 is the Rose Bug, Rose Beetle, or Rose Chafer, as it is vari- 

 ously called (Cetonia aurata). It is a pretty little insect, 

 with glossy, golden-green back and nicely-marked wing 

 cases, the under surface of its body being brown. 



Remedies. — Insecticides used when the plant comes 

 into bud and hand-picking will keep them in check ; a 

 vigorous shaking of the bush disturbs them. 



Rose Scale Insects. — The rose is not exempt from 

 attacks of scale insects, forced roses suffering most of all. 

 These insects attack the stems and branches ; they cling 

 to the bark and suck the sap from the bush, and if the 

 host is badly attacked it yields very inferior flowers, 

 and will take a year or two to recover. The scales are 

 like tiny shells ; they generally exist in colonies, and, to 

 all appearances have no movement. Aulacaspis roses 



