2 BULLETIN 847, 17. S. DEPARTMENT OE AGRICULTURE. 



Biltmore, N. C, Winthrop, Me., and Munising, Mich. First-hand ob- 

 servations on the species were made also in many other localities and 

 more or less original data obtained therefrom. The studies were 

 continued over the period 1911 to 1918. 



HISTORY. 



The roundheaded apple-tree borer was first described by J. C. 

 Fabricius in 1787 (l) 1 as Saperda Candida, In 1824 it was rede- 

 scribed by Thomas Say (2) as Saperda bivittata, and by this name 

 it was commonly referred to by Harris, Fitch, Walsh, and other early 

 American writers on economic entomology. From 1875 to 1885 

 Riley, Lintner, and others recognized the priority of Fabricius's 

 name, and since that time the species has been rightfully designated 

 Saperda Candida. 



The insect is native to North America and originally fed upon 

 and bred within a limited number of forest trees and shrubs belong- 

 ing to the family 

 Rosaceae. When 

 cultivated orchards 

 of apple, pear, and 

 quince began to be 

 established in the 

 eastern part of the 

 United States the 

 borer soon found its 

 way from the forests 

 into the orchards 

 and did much dam- 

 age to valuable fruit 

 trees. There are 

 many records of serious injury in New York and throughout the New 

 England States, beginning as early as 1825. Apple trees seem to have 

 suffered most ; in some cases entire orchards were destroyed, and the 

 loss of 50 per cent of the trees was not unusual. Felt and Joutel (6) 

 cite numerous historical references showing the widespread and de- 

 structive nature of the insect in the days of pioneer orcharding in 

 this country. In more recent times, as the orcharding interests of 

 the country have developed, losses from this insect have increased 

 rather than diminished. At the present time it is an orchard pest of 

 primary importance throughout a great portion of the apple-growing 

 region east of the Rockv Mountains. 



DISTRIBUTION. 



The known range of the roundheaded apple-tree borer may be 

 bounded by a line extending from near the mouth of the St. Law- 



Fig. 1. — Distribution of the roundheaded apple-tree borer 

 (Saperda Candida). 



1 Numbers in parenthesis refer to " Literature cited," p. 41. 



