344 Landscape Gardening 



out perfect insects to lay another brood of eggs. They are 

 destroyed by saturating the egg masses with creosote at any 

 time during the fall and winter and by spraying with arsen- 

 ate of lead as soon as they begin to feed in the spring upon 

 the young leaves. 



The Leopard Moth {Zeuzera pyrina). — Among the more 

 recent insects injurious to ornamental trees and shrubs is 

 the leopard moth. This pest was first found by Mr. R. W. 

 Curtis, of the Arnold Arboretum, in 1909. Soon after this 

 date it was found upon the elms and other trees in the 

 grounds of Harvard College. 



It feeds upon nearly every ornamental tree and shrub 

 except the evergreens. Its eggs are laid singly or in small 

 groups under the bark and in crevices of the trunks and 

 main branches. 



The young larvae are very small, but at maturity are nearly 

 2 inches long. They feed upon the smaller branches, causing 

 many of them to break off. The best remedies are spraying 

 the trunks and main branches with a strong mixture of 

 arsenate of lead at the time the eggs hatch, and digging out 

 the larvae while they are small. If discovered upon one's 

 trees aid should be called from the experiment stations or 

 the Entomological Bureau of the Department of Agriculture. 



There are a great many other less injurious insects that 

 often appear in small numbers on single trees or within 

 limited localities, sometimes increasing rapidly for a time 

 and then disappearing; but the Hmits of this volume will 

 not allow of further space for their description. We may 

 briefly say that in a general way the remedies already 

 described may be applied to all insect pests, i.e., all chew- 

 ing insects to be destroyed by the use of arsenate of lead 

 and hellebore, and all sucking insects by the kerosene 

 emulsion, lime-sulphur and soluble oil. 

 ^Whenever a new insect appears, if doing harm to any 



