CONTENTS 



PART I. 

 THE SPRUCE INVESTIGATION. 



Page. 

 INTRODUCTORY, ...... . 197 



Acknowledgements, 198. List of published titles by the author, 

 referring to work and results of the spruce and pine investigation, 200 



THE SPUCE INVESTIGATION, ..... 203 



The Spruce in West Virginia, 203. Common and technical names, 

 203. Description. 207. 'Distribution, 208. Some of the early dis- 

 turbing influences, 211. Mountain pastures, 213. The original 

 area greatly reduced, 215. Present conditions in the spruce area, 

 210. "Probable future of the spruce area as indicated by present 

 conditions, 221. Commercial influences in their relation to the 

 future of the spruce area, 223. Agricultural influences, 225. The 

 importance of perpetuating the forest resources of the area as a 

 source of wealth to its inhabitants and the State, 226. The rela- 

 tion of entomological research to the preservation and perpetu- 

 ation of forests, 229. 



REPORT ON INVESTIGATIONS TO DETERMINE THE CAUSE OF THE UN- 

 HEALTHY CONDITION OF THE SPRUCE BETWEEN 1880 and 189 5, 230 



Disturbing influences, 230. History and progress of dying spruce 

 timber in the spruce area, 232. Cause of the first trouble, 235. 

 Cause of the second trouble, 237. A circular letter to lumber 

 companies, 238. Distributing the European bark-beetle destroy- 

 er, 239. End of the trouble, 239. Rapid decay of dead spruce 

 timber in one section of the spruce area, 239. Wood-peckers the 

 principal enemy of the destructive sapwood borer, 242. Present 

 condition as to insect enemies, 242. 



THE PRINCIPLE INSECT ENEMIES OF THE SPRUCE IN WEST VIRGINIA, 244 

 Bark Miners, 244. The destructive pine bark beetle, 245. The 

 destructive spruce bark beetle, 246. Le Conte's spruce bark bee- 

 tle, 251. The cosmopolitan spruce bank beetle, 252. Eichhoff's 

 five-toothed pine bark beetle, 253. Say's pine bark beetle, 253. 

 Flat headed spruce bark miners, 254. Round headed spruce bark 

 miners, 255. 



Wood Miners, 255. Timber or ambrosia beetles, 256. The spruce 

 timber beetle. 256. Round headed wood miners, 258. The des- 

 tructive spngice wood miner, 259. Injury to terminal branches by 

 the white pine weevil, 259. Injury to twigs by the spruce gall 

 louse, 260. 



PRINCIPAL INSECT FRIENDS OF THE SPRUCE, OR ENEMIES OF THE IN- 

 SECT ENEMIES, ....... 262 



Predaceous beetles and their larvae, 262. The Clerids, 262. Ameri- 

 can bark beetle destroyer, 262. Staphylinids or rove-beetles and 

 their larvae, 264. Histerid beetles, 265. Nitulid beetles, 265 

 Tenebrionid beetles, 266. 



PARASITIC ENEMIES, . . . . , . . 266 



Ichneumonid parasites, 266. Braconid parasites, 266. Chalcid 

 parasites, 267. Trachinid parasites, 268. 



DISEASES OF INSECT ENEMIES OF THE SPRUCE, . . 268. 



BlRDS AS FRIENDS OF THE SPRUCE, . . 269 



OTHER BENEFICIAL ELEMENTS 269 



