AND OTHER INJURIOUS INSECTS OF I907 AND I908. 



THE SCURFY SCALE, 



Chionaspis fnrfura Fitch. 



III 



a- i 



Fig. 54. The Scurfy Scale. Bureau of Kntomology, U. S. Dept. Agriculture. 



Exceedingly abundant in Minnesota, giving trunks and branches 

 of affected ti-ees a "scurfy'' appearance. This scale is oval, somewhat 

 elongated, about one-tenth of an inch long, pointed at one end and 

 white. It affects poplars, cottonwood trees, mountain ash, willows 

 (in one instance a grove of the latter were found in 1908 to have 

 been destroyed by this insect) and other trees and shrubs. A form 

 belonging to the same genus is found on the elm. In the winter, 

 eggs are found under the scale of the feinale. The young hatch in 

 the spring, move about on the tree for a while, and then settle down to 

 a sedentary life, sucking the sap from the tree, and secreting a scale. 

 There is probably but one generation. 



Remedies: A spray of kerosene ennilsioii, one part of the stock 

 solution to nine or ten of water applied to infested trees in spring 

 about the first of June, zvould kill the young if they had hatched. 

 Two sprayings with this solution, one the last of May and one about 

 June i^th in this latitude, should insure the killing of the young on 

 trunk and branches. The lime-sulphur washes in winter, when the 

 trees are dormant, is a killing spray for adult scales. All necessary 

 pruning should be done before spraying, and the infested cuttings 

 im>mediately burned. Careful scraping of infested bark will renvove 

 many scales unthout injuring the tree. 



