206 



PESTS OF GARDEN AND FIELD CROPS 



plants will die. Cucumbers and tomatoes usually are badly infested, 

 but almost an}^ vegetables or flowering plants grown in greenhouses 

 may be attacked. 



The most effective remedy is fumigation with hydrocyanic acid gas. 

 Some benefit will be derived from spraying with whale-oil soap, 1^ 

 ounces to 1 gallon of water. 



Mealy Bugs 



Slow-mo\ing, oval, soft^bodied bugs, one tenth to one sixth of an 

 inch long, the body covered with a whitish, powdery secretion, infest 

 various plants grown under glass. In the South they are a nuisance 



Fig. 255. — Mealy Bugs on melon. Original. 



on citrus fruits. The Citrus Mealy Bug, Pseudococcus citri Risso, and 

 a closely related form, Pseudococcus longispinus Targ., are common 

 species. 



The young are small, red, and fairly active at first. The adult males 

 are winged. 



Contact insecticides, especially such as contain soap or oil, are effec- 

 tive remedies. They should be applied with considerable force in 

 order to penetrate the waxy powder with which the bodies of the 

 insects are coated. 



