122 PRACTICAL LANDSCAPE GARDENING 



flowering wood the season previous, should be pruned Just after 

 they have flowered. Lilacs, Golden Bell, Japanese Quince and 

 similar Spring blooming shrubs are in this class. The pruning 

 should not be too severe, simply enough to keep the plants in shape 

 and to allow sunlight and air to all parts. The Fall flowering shrubs, 

 such as the Rose of Sharon and Hydrangeas, bloom on wood made 

 during the immediate Summer. Such shrubs should have a vigorous 

 Winter, or early Spring pruning. 



INSECT PESTS 



Insect pests attacking trees and shrubs are mostly of two kinds: 

 those that injure by eating the foliage, such as the Elm Leaf Beetle, 

 and those that injure by sucking, such as the various scales and 

 plant lice. 



For the leaf chewing insects a spraying with some poisonous 

 substance that will readily adhere to the leaves is most eSective. 

 Paris green and arsenate of lead are recommended. These sub- 

 stances may be purchased in commercial form, prepared for such 

 use, and accompanied by full instructions for proper apphcation. 



For scales and plant lice some remedy that kills by contact must 

 be applied. Kerosene and soap emulsions are the best. 



A wide band of burlap tacked around the tree with an overlap 

 is very useful in arresting the progress of caterpillars. Such over- 

 laps should be turned frequently and the caterpillars destroyed. 



