820 FIFTH REPORT OF THE ENTOMOLOGICAL. COMMISSION. 



regions that the borers were the cause of the disease. This man re- 

 peatedly removed the bark, and, as he said, "found it full of little white 

 worms." He also assured me that he found similar worms in liviiig 

 spruce trees, and that the result of their work was to girdle the tree. 



From conversations with diflt'erent lumbermen it appears that a spruce 

 tree a foot in diameter gets its growth in from forty to fifty years. The 

 larger trees can be culled out of the same lumbering region every ten 

 years. Lumbermen have the impression that a spruce tree grows rap- 

 idly. This of course depends on the soil, position, and climate. We 

 have found the past season that spruce saplings about 4 feet high get 

 their growth in three years ; it is easy to ascertain this by the difference 

 in the color and appearance of the bark. Whether the spruce grows more 

 rapidly than hard- wood trees remains to be ascertained. Standing in a 

 yard of a house in Maine, a sugar-maple, which had been a rapid grower, 

 and which we know to be about forty-eight years old, measured, in 

 September, 1884, 1 foot from the ground, 24f inches in diameter. The 

 Thorndike oak, on the campus of Bowdoin College, raised from an 

 acorn planted on the first commencement day of the college, on the first 

 Wednesday of September, 1806, now measures (1885), at 1 foot from the 

 ground, 30 inches in diameter, having therefore attained its present 

 dimensions in seventy-eight years. 



From Mattawamkeag we went to Moosehead Lake. Throughout the 

 great range of forests to be seen from the lake at and south of Mount 

 Kineo no dead spruces were to be observed ; though a single bud-worm 

 {Tortrix fumiferana) was beaten from a young spruce July 6. Here, 

 however, as everywhere else, dead spruces occasionally occurred whose 

 bark was filled with Scolytid beetles. 



From B. S. Ooe, esq., of Bangor, to whom we are indebted for infor- 

 mation regarding the destruction of spruce timber in Maine, we learned 

 that large tracts of spruce timber near Kennebago Lake, on the height 

 of land between the Androscoggin and Forks of the Kennebec, had been 

 destroyed. 



Mr. Ooe also informed us that he learned from General Smith, of 

 Norridgewock, that the spruce growth about that town and Waterville 

 early in this century had been diseased, and died very much as in the 

 past few years. 



From various persons we learned that the evil is now abating, and 

 without doubt if the tracts of dead spruce, at least those near settle- 

 ments or villages, could be cut down and removed, leaving, however, 

 the spruce undergrowth, a new growth of spruce would spring up, 

 which ill forty or fifty years could be profitably lumbered. 



The disease due to hark and timber beetles. — From the foregoing state- 

 ments the reader will justly infer that the great destruction of spruce 

 and forest trees throughout northern Kew England in 1879, and four or 

 five years following, was due to the attacks of beetles, chiefly the small 

 cylindrical bark-borers, belonging to the coleopterous family Scolytidce; 



