INSECT ENEMIES OF THE PINE IN THE BLACK HILLS 

 FOREST RESERVE. 



REQUEST, AUTHORIZATION, AND INSTRUCTIONS. 



The work herein reported was undertaken by request of Mr. Gilford 

 Pinchot, Chief of the Bureau of Forestry, under authorization from 

 the honorable Secretary of Agriculture and instructions from Dr. L. O. 

 Howard, Chief of the Division of Entomology. 



THE INVESTIGATING TRIP. 



The investigations were conducted, in company with Mr. Pinchot 

 and his chief held assistant, Mr. Griffith, on September 1 to 4, 1901, 

 along a route traversed through the reserve from Spearfish, via Iron 

 Creek, Bear Gulch, and Cement Ridge, South Dakota, Rifle Pit, 

 Wyoming, and Spearfish Creek, to Lead, S. Dak. 



THE CONDITIONS OBSERVED. 



Vast numbers of rock pine (Pinusponderosa scopulorwn) that were 

 dying, or had died within recent years, of sizes ranging in diameter 

 from 4 inches to the largest trees, were observed along the route. 

 The dying trees occur in clumps of from a few examples to many 

 hundreds, and in some sections, as viewed from the summit of Cement 

 Ridge and other favorable points, the dying, recently dead, and old 

 dead trees cover large areas. 



THE AMOUNT OF DEAD TIMBER. 



Mr. H. S. Graves a estimated in 1897 that about 3,000 acres of pine 

 in the Black Hills Forest Reserve had been killed. Further data fur- 

 nished by the Bureau of Forestry show that the actual amount of dead 

 timber, as determined by Mr. Griffith and party in a detailed survey of 

 the timber resources of the reserve in 1901, is, "An average stand of 

 1,956 feet board measure of bug-killed timber on 116,000 acres, giving 

 a total of 226,890,000 feet board measure." 



HISTORICAL REFERENCES. 



It is the general opinion among settlers and others who have had an 

 opportunity to note the conditions affecting the pine that the dying 

 timber commenced to attract attention about six or seven years ago, 

 or about 1895. 



a Nineteenth Annual Report U. S. Geological Survey, 1897-98, Part V, p. 87. 



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