BULLETIN OF THE 



No. 67 



Contribution from the Forest Service. Henry S. Graves, Forester. 

 March 17, 1914. 



(PROFESSIONAL PAPER.) 



TESTS OF ROCKY MOUNTAIN WOODS FOR 

 TELEPHONE POLES. 



By Norman de W. Betts and A. L. Heim, 



Engineers in Forest Products. 



POLE SUPPLY IN THE ROCKY MOUNTAIN REGION. 



The rapid extension of telephone and power lines in the West makes 

 the question of pole supply one of increasing importance. Tests 

 described in this bulletin show that both green and fire-killed lodge- 

 pole pine and fire-killed Engelmann spruce will, under certain con- 

 ditions, make suitable pole timbers. Western red cedar has long 

 been the standard pole timber in the Western States. It has held its 

 place mainly on account of its durability in contact with the soil, 

 though its light weight has also been a very desirable feature. The 

 tree (Thuja plicata) grows principally in Washington, Oregon, and 

 northern Idaho. In addition to its wide use for poles, it is extensively 

 cut for lumber, and especially for shingles. In the States south of its 

 region of growth the cost of cedar is high, owing to the great dis- 

 tances over which it must be transported. Moreover, the heavy 

 drain on the available supply must soon result in higher stump- 

 age prices. There are at present in both the Rocky Mountain and 

 Coast Ranges abundant stands of lodgepole pine (Pinus contorta), often 

 called by local lumbermen "white pine,'' of little value for lumber, 

 but well adapted for poles. Lodgepole pine is not naturally durable 

 in contact with the ground, and for that reason has not been able to 

 enter the field as a competitor of western red cedar. The general 

 adoption of preservative treatment I by railroad and telephone com- 

 panies, however, has changed the situation. At an additional cost 

 for treatment that still leaves the pine pole the cheaper of the two 

 in most of the markets outside the region where cedar grows, the 

 pine may be made to last longer than untreated cedar. Lodgepole 



1 The preservative treatment of poles is discussed in Forest Service Bulletin 84. 

 Note.— This bulletin gives the results of tests on western red cedar, lodgepole pine, and Engelmann 

 spruce poles to determine their suitability for telephone lines. Values are presented for fiber stress at 

 elastic limit, modulus of rupture, stiffness, and modulus of elastic resilience. Of value 1>o lumbermen 

 in the Rocky Mountain and Pacific Coast States and to users of telephone poles. 



22740°— 14 1 



