THE EUROPEAN ELM SCALE 



{Gossyparia spuria, Modeer) 

 By Samuel B. Doten 



In the study of many insect problems there are three related sides 

 of the matter to be taken into consideration; the nature of the pest, 

 the nature of the infested plant, and human nature, which third fac- 

 tor is the most difficult of the three. 



"When the San Jose Scale first appeared in western Nevada, apple 

 trees were much used in the principal towns as shade-trees in door- 

 yards ; they were hardy and ornamental trees and in favorable years 

 were profitable as well. With the advent of the Pernicious Scale they 

 became diseased and unsightly, many were ruined, while others only 

 slightly infested were cut down because it had become necessary to 

 have them sprayed every year or two. Now the reason for this whole- 

 sale destruction of apple trees lay not so much in the nature of the 

 pest or the nature of the tree as in human nature. Before the Pernic- 

 ious Scale was introduced, the apple tree within the city limits was 

 looked upon as an ornamental tree which often proved a source of no 

 small profit; after the Scale became established, these trees became 

 much less ornamental, less profitable, .and a source of yearly annoyance 

 and expense during the spraying season. The Horticultural Law in Ne- 

 vada makes spraying compulsory, the labor supply was short and 

 its price high; spraying was expensive and none too efficient. The 

 situation was such that many householders came to regard their apple 

 trees as sources of more annoyance than profit and so had them cut 

 down. 



At the present time the European Elm Scale presents a somewhat 

 similar problem. For several years it has been injuriously abundant 

 in the neighborhood of Carson City, in more recent years it has ap- 

 peared in Eeno where most of the residence streets are lined with 

 young elms. Some of these have been killed outright, while hundreds 

 of others have been greatly injured. Up to the present time the elms 

 have been our most highly-valued shade trees, in this new country they 

 are of necessity still young and very susceptible to the attacks of the 



