l^he Biltmore Stick. 409 



ing diagrams for several diameters and applying the scale for 

 these diameters. 



For actual use a straight stick four and one-half feet long, an 

 inch wide and three-fourths of an inch thick with a slight bevel 

 on one side should be selected and the scale marked or burned 

 upon it so that the graduations occur on the bevel edge. The 

 stick should be capped or shod at each end with a light metal 

 ferule to prevent wear. The stick length, four and a half feet, 

 may be used to check the breast height point on the trees meas- 

 ured. The twenty-five inch point should be marked on the back 

 of the stick so the user may check up his arm length occasionally. 



To use this stick the observer holds it horizontally against the 

 tree four and a half feet from the ground and twenty-five inches 

 from his eye which should be at the same level as the stick itself. 

 The zero end of the stick should lie in the line from his eye to 

 one outer edge of the tree. Then, turning his eye, the observer 

 should note where the line of sight between his eye and the other 

 edge of the tree crosses the scale. The reading on the scale at 

 this point gives the diameter of the tree. 



When the diameters of only a few trees are to be taken, the 

 tracing scale may be attached to a suitable stick with thumb tacks 

 and the readings made without taking the trouble to mark the 

 scale on the stick itself. 



The writer made a Biltmore stick out of white oak according 

 to these specifications except that the ends were not shod and 

 the stick itself was only four feet long. The gradations and 

 figures were burned on the stick with a pyrographic needle after 

 which the instrument was coated with shellac. 



To test the accuracy of this stick the writer with two assistants, 

 one equipped with the Biltmore stick and the other with sixty 

 inch calipers, examined 975 trees of four different species in the 

 cedar-fir-hemlock forest near Berlin, Wash. The diameter of 

 each tree was taken at the same point with the stick and with the 

 calipers, the stick man calling his reading first. These diameters 

 ranged from ten to sixty inches. The average diameter for the 

 975 trees was 28.56 inches measured with the calipers, and 28.66 

 inches measured with the Biltmore stick thus giving an average 

 difiference of only one-tenth of an inch. 



Both regular and irregular trees were measured just as they 

 occurred in the stand. Fifty-nine of these measurements were 



