230 WEST VIRGINIA EXPERIMENT STATION. 



the forests in this and other regions of the State. Therefore, 

 the subjects of past and present distribution and condition of 

 its forest trees ; the animate and inanimate influences which 

 have affected the conditions of its plant and animal life, its 

 wealth in forest resources, its possibilities and its probable fu- 

 ture have all been considered and studied mainly in their re- 

 lation to entomological research. 



REPORT ON INVESTIGATIONS TO DETERMINE THE CAUSE OF THE UN- 

 HEALTHY CONDITION OF THE SPRUCE BETWEEM 1880 AND 1893. 



A preliminary report on the black spruce investigation was 

 published in the Third Annual Report of the Station, pp. 93- 

 102, and in Bulletin 17, as a reprint from the Annual Report, 

 dated May, 1891. After this report was submitted, the investi- 

 gation was continued and a number of special trips made 

 through the spruce region for this purpose, in the following 

 months and years: March, 1891; July, 1891; May, June and 

 July, 1892; May and July, 1893; May, July and October, 1894. 



All the principal sections of the region, where the spruce 

 predominated, were visited, and a pretty thorough study made 

 of the conditions of the region and its timber, which is referred 

 to in another part of this report. Much additional information 

 and new facts have been obtained upon the insect infesting the 

 spruce, but as a considerable portion of it is of a technical 

 nature, I will simply mention in this report, some of the lead- 

 ing features of economic interest, and reserve the other for a 

 more detailed special report on spruce tree insects. 



1 am now able to bring together a chain of data and evidence 

 upon which to base more definite conclusions than was possible 

 when Bulletin 17 was published. 



DISTURBING INFLUENCES. 



The earliest record we have of -disturbing influences in the 

 spruce forests, which would offer favorable conditions for the 

 increase of destructive insects, was the hunters' burnings, pion- 

 eers' clearings and stockmans' hacking during the first half of 

 the present century; also that resulting from the cutting of 

 spruce timber, (about 100 acres,) around or near the Dobbins 



