187 

 DAMAGE TO FORESTS BY THE DESTRUCTIVE PINE BARK-BEETLE. 



(Dciidructouns froutalis Ziiuiii.) 

 Hy A. I). lIoHKixs, Monjantonii. W. la. 



It appears that an uuliealtliy coudition of the pine forests in West 

 Virginia and Virginia has existed in certain points in the Allegheny 

 Mountain range and adjacent foothills since about the year 1888, but 

 had only attracted local attention until within the last two years, when 

 its rapid spread and increasing devastation brought the matter to 

 public notice, and it was referred to this Station, and to me, for investi- 

 gation. I have, therefore, made two extended journeys through the 

 eastern portion of our State, one in May and the other in July of this 

 year, for the purpose of ascertaining tlie character and eause of the 

 trouble and the extent of the damage, and also to discover, if possible, 

 a remedy. 



It was found that when this trouble commences in a healthy forest 

 groups of trees numbering from two to a dozen or more are noticed 

 dying the first year. The foliage on such trees first turns yellow and 

 then ]-ed, as if killed by fire. The second year this peculiar condition 

 will have spread until the groups of dying trees extend over one to ten 

 or more acres; and by the third year the entire forest of pine trees of 

 all kinds, on hundreds of acres, is often found dead and dying. 



After studying all the conditions found, and a due consideration of 

 all the visilile and probable elements which might produce them, I was 

 convinced that a single species of Coleopterous insect, Dnidroctomis 

 frontalis, was to blame for the primary attack and resulting death of 

 the trees. 



From personal observation it is found that the dead and dying con- 

 dition of the Pine extends from near the Pennsylvania line in Maryland 

 on the north; through Hampshire, Hardy, Grant, Pendleton, Eandolph, 

 Pocahontas, and Greenbrier, to Summers and Ealeigh counties in West 

 Virginia on the south; and from inquiry and correspondence I learn 

 that the same condition extends through about an equal area in Vir- 

 ginia. Therefore, it would seem that the ravages of this beetle extends 

 over an area of at least 10,000 square miles, including portions of West 

 Virginia, Virginia, and Maryland, on which five species of Pine and 

 Black Spruce are being damaged and killed to a- greater or less extent 

 l)y them. In certain sections entire forests of Pine, including all spe- 

 cies on several square miles, are dead, and have been a total loss. The 

 greatest destruction has been in the forests of the common Pitch Pine 

 (P. rigida Miller), and the Scrub Pine (P. inops Ait), and in the less 

 common but more valuable Yellow Pine (P. ecMnata Mill). 



The extensive and valuable forests of Black Spruce {Abies [Picea ma- 

 rianna] nigra Pain), and White Pine {P'tnus strobus L.) in West Virginia, 

 are being invaded by the insects; therefore, owners who have large in- 



