130 
THE SCOLYTID BEETLES. 
aggregating approximately 1,200 acres, although it is probable that 
the insect was present before the fire occurred. He states as follows : 
Two or three years after trie fire serious work of the insect was first made apparent, 
and local observers state that the beetle work has steadily increased until the entire 
spruce stand is threatened with insect destruction. In his 1904 report Mr. F. G. Plum- 
mer stated, "Notwithstanding the fact that the summits of the Sierra Blanca afford 
apparently ideal conditions for the growth of the spruce, about 20 per cent of the 
standing trees are dead or dying. This gives the forest the appearance of having been 
scorched by a fire not severe enough to utterly destroy it. For this no cause was found. 
*■ * * 
Fig. 81.— Average-sized Engelmann spruce killed by fire and the Engelmann spruce beetle. 
National Forest, at elevation of 10,150 feet. (Original.) 
Lincoln 
The insect work occurs at an elevation above 9,000 feet and will probably extend 
to the altitudinal limit of the spruce in case it has not already done so. It was found 
in trees varying from 6 to 20 inches, which had not been subject to other injury. 
Approximately 1,000 acres of the headwaters of the South Fork of the Kio Bonito 
have been completely killed by the combined effect of fire and insects, and other 
similar areas exist in the reserve. 
Mr. F. G. Plummer, of the Forest Service, in a report entitled 
"Forest conditions in the Lincoln Xational Forest, Xew Mexico 7 ' a 
estimates a total stand of 29,027,000 feet, board measure, on 13,142 
acres. Of this, 1,480 acres, or about 9 per cent, has been burned. 
a Professional Paper No. 33, series H. Forestry. 11, U. S. Geological Survey. 
