34 



THE WESTERN HEMLOCK. 



Matlock in Mason County. It will be noticed that the percentage of 

 Hemlock is highest on the coast and on the foothills, which is in pro- 

 portion to the increase in rainfall. 



The data for estimating the stand given in the following tables were 

 obtained by the strip valuation survey method, which is in general 

 use by the Bureau of Forestry. Strips 1 chain (66 feet) wide and 10 

 chains long to the acre were run in several directions through the forest 

 to be estimated, and all trees on these strips were counted and meas- 

 ured at breastheight by calipers, or with a measuring tape, a separate 

 tally being kept for each acre. At Orting, for example, the camps of 

 the St. Paul and Tacoma Lumber Company were taken as headquarters, 

 and the valuation survey parties followed compass courses radiating 

 from the camps as a center, like spokes from the hub of a wheel. Since 

 eight of these strips make a mile, the 325 acres measured at Orting aggre- 

 gate a strip over 40 miles long and 66 feet wide. The contents of the 

 trees in these strips were computed from the volume tables, constructed 

 from the actual scale of felled trees. By this system the stand on large 

 areas can be determined with great accuracy and at small expense. 



All trees 20 inches and over in diameter breasthigh were scaled, 

 which in most instances probably gives a trifle higher total stand than 

 would actually be cut at present, since trees less than 2 feet are now 

 seldom taken. No attempt was made to figure locally the cull due to 

 unsoundness, for it is so variable that only confusion would result. 

 All living trees 20 inches and over in diameter were scaled, whether 

 defective or not, and a cull of 20 per cent was deducted for crooked, 

 scrubby, or otherwise poor trees. 



The number of acres actually measured in each locality is given at 

 the head of each table. It should be borne in mind that these were 

 carefully distributed over a large area and so far as the number and 

 size of the trees are concerned represent the stand with very fair accu- 

 racy. The actual merchantable yield in board feet is necessarily 

 dependent upon the standard in cutting. The yield of bark is com- 

 puted for merchantable Hemlock only and assumes that the trees will 

 be peeled to a point 17 inches in diameter in the tops. 



Table 10. — Stand and yield per acre in typical localities. 



WILKESON (400-YEAR-OLD STAND.) 

 [Average of 35 acres.] 



