The Measurement ef Saw Logs 8r 



measure, respectively, or an average total of fourteen feet for the 

 logs after sectioning. Or, to take a more extreme case : 6-inch 

 logs, 40 feet long, scale by Doyle 10 feet board yneasure. Cut 

 to 8- foot sections and again scaled by Doyle the parts will be 

 found to give an average scale of 55 feet board measure per log, 

 or an increase of some 400%. These results were demonstrated 

 by measurements of the taper shown by over four thousand pine 

 and spruce logs. 



As is well known, trees of the same species, age, and stand 

 differ greatly in the amount of taper shown. Individual logs 

 from the same tree differ widely also. Here as elsewhere in for- 

 est measurements, the forester falls back on the great law of 

 averages. The average taper in any given locality for any par- 

 ticular species may be easily determined with sufficient accuracy 

 for practical purposes by the measurement of a few hundred logs. 

 If greater accuracy be required for scientific purposes, a few 

 thousand will be ample. Measurements of the average taper 

 shown by logs representing the commercial trees of Northeastern 

 America have revealed the welcome facts : ( i ) That the average 

 taper does not differ greatly in different localities or with different 

 species ; (2) That it is less in good straight clean sawing timber 

 and greater where the logs are rougher, the larger taper in the 

 latter case compensating largely for the increased waste in edging 

 the lumber from the inferior logs ; and (3) That it never falls 

 below one inch in eight feet when the logs are taken as they 

 come in modern logging operations. Below are summarized the 

 results of a few such studies : 



No. of Logs Species. Diameter of Logs Taper in in 



measured. measured. per 8 ft lineal. 



1070 White pine 6 to 33 1.22 



3000 Spruce 7 to 18 1.30 



300 Balsam Fir 6 to 14 1.26 



Chestnut ' ii to 25 1.42 



Loblolly Pine^ 10 to 20 .9610 1.20 



" " over 20 1.20-!- 



A mixed lot of Adirondack hardwoods gave an average taper 

 of 1. 17 inches. On page 87 of Bulletin No. 22, Bureau of For- 



* Chestnut in Southern Maryland, R. Zon. Bulletin No. 53, Bureau of 

 Forestry, p. 28. . 



^ Loblolly Pine in Eastern Texas, R. Zon. Bulletin No. 64, Bureau of 

 Forestry, p. 21. 



