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tendency to renew themselves by sprouts from the roots or the base 

 of the tree. 



Doctor Hopkins, who, between 1890 and 1900, made a study of 

 insects injurious to the locust in West Virginia, is authority for the 

 following statement in regard to the work of the locust leaf -mining 

 beetle in West Virginia: 



In 1890 and 1891 the locust trees in Monongalia, Marion, Harris )n, and Lewis counties, 

 W. Va., were severely damaged by the locust leaf-mining beetle (Odontota dorsalis]. In 

 1891 and 1892 a large percentage of the trees died. In some localities practically all of 

 the medium and large trees were killed. In 1892 it was not so common in the counties men- 

 tioned, but the trouble seemed to extend from this central area of infestation to adjoining 

 counties and other sections of the State. Between 1892 and 1895 the beetle and its work 

 were noticeably less common in the State, but from 1896 to 1898 it reappeared in great num- 

 bers and caused serious damage to the remaining locust in the counties mentioned, and, as 

 before, extended its ravages to other sections, including those which had been exempt. 



The range of severe injury observed in 1905, during the study of the 

 possibilities of forest planting in this region, is as follows : 



Pennsylvania: Westmoreland County, west of Chestnut Ridge; 

 Fayette County, west of Chestnut Ridge, and part of the ridge; Alle- 

 gheny County between the Allegheny and Monongahela rivers, and 

 other parts of the county in varying degrees of severity. Washington 

 County along the Monongahela River, with local spots of severe injury 

 and of slight damage throughout the remainder of the county; Greene 

 County along the Monongahela River, and a few local spots of severe 

 injury in other parts of the county. 



West Virginia: The Panhandle, especially along the Ohio River; 

 Monongalia County; Marion County; Preston County, west of the 

 mountains; Harrison County; Taylor County. 



Observations in this region have shown conclusively that young 

 natural stands and forest plantations of locust started under such 

 adverse conditions may survive the attack for several years, but will 

 not reach a merchantable size. Therefore it should be fully under- 

 stood that within the counties where this exceptional injury occurs 

 locust plantations should not be made, since failure is certain. 



The locust borer. Injury by this insect has not been so widespread 

 as that by the leaf-mining beetle. Where it is numerous, however, 

 its effect is so severe that it becomes of great importance locally. 

 The work of this insect is very characteristic and readily recognized. 

 The stems and larger branches of saplings and older trees were found 

 to indicate injury by the locust borer early in July by sawdust in the 

 crevices of the bark and around the base of the stem. On splitting 

 the wood, mines were found extending in all directions through the sap- 

 wood and heart wood. Vigorous boring at one point on the stem of a 

 young tree results in weakening it so much that the wind can readily 

 break it off. Older trees frequently lose large branches or the upper 

 part of the stem. When very numerous the borers will kill the trees 



