8 
The evidence found by the writer in old dead standing and felled 
trees indicates that the pine-destroying beetle has been present for a 
much longer time. It was also evident that much of the devastation 
supposed to have been caused by forest fires was caused, primarily, by 
insects. 
Mr. Graves, in his exhaustive report on the Black Hills Forest 
Reserve,* refers, on page 87, to insects and the dead pine timber as 
follows: 
On the high limestone divide, from near Crook Tower to the head of Little Spear- 
fish Creek, there are numerous patches of dead and dying timber. These patches 
are usually rectangular in shape and follow the tops of the divide and ridges, or run 
lengthwise up and down the slope. This forest has for the most part not been lately 
burned, and there is a heavy matting of litter and humus on the ground. The injury 
is confined to the limestone formation and to high elevations. The trees are in many 
cases second growth and apparently perfectly thrifty. This injury is probably 
caused by insects. On all dead and dying trees examined were found bark borers, a 
species of the Scolytidze, working under the bark. In most cases the leaves were 
clinging to trees which had been dead for several seasons. While these borers do not, 
as a rule, attack vigorous trees, no other cause of the death of this timber could be 
found. 
Mr. H. E. Dewey, writing to the Division of Entomology from Lead, 
S. Dak., on August 12, 1899, stated: 
* * * There have been none in the trees this year until last Wednesday, the 
9th. On that day there was a southwest wind, and aswarm of them came. My 
dwelling is in what was a grove of young native Black Hills pines. The bugs settled 
on the house like a plague of locusts. At night they left the house and seattered 
about. I have examined the trees, and with one exception do not find that they 
attacked them. This one excepted tree is a sight. Hundreds of bugs settled on it 
during the night, and by morning they had buried themselves out of sight in the 
trunk. As they bored their way in, the dust from their boring, which was very 
fine, filtered out from the top to the bottom of the tree like fine sawdust, and fell 
about the tree on the ground. They could be plainly heard at their work as they 
bored into the wood. The tree was a vigorous young pine about 15 feet high and 6 
inches in diameter at the ground, and there is no apparent reason why they should 
select it more than others. Last year they were here in June. 
The following copy of a letter addressed to the Department of the 
Interior, Division of Forestry, was submitted to the author from the 
Division of Entomology, with a specimen of the insect, which, together 
with the specimens sent with Mr. Dewey’s letter, formed the material 
from which the species was named and descriptive notes were made. 
The letter is dated Piedmont, S. Dak., August 14, 1898, and reads as 
follows: 
Many of the pine trees in this vicinity are dying. Small holes appear in the bark, 
a reddish pitch exudes, the leaves turn brown, and in a few weeks the tree dies. I 
think the mischief is done by the small black insect inclosed herewith, which I found 
in one of the holes. Is there any remedy? 
«Nineteenth Annual Report U.S. Geological Survey, 1897-48, Part V, pp. 67-164. 
