342 



Exotic Conifers in Britain. 



As, however, this tree was rather larger than the average, 

 girthing, as it did at breast height, 4 feet 7 inches (17*5 inches 

 diameter), Mr. Pitcaithley was good enough to select a normal 

 standing tree, girthing 4 feet 1 inch (15*6 inches diameter, 1,327 

 square feet section area) at 4^ feet from the ground, and this 

 was duly measured in 6 feet lengths. Its total height was 83 

 feet, the point of 3 inches in diameter being reached at 75 feet. 

 The true cubical contents, neglecting top and branches, were 

 found to be 50*25 feet, or, calculated according to English 

 measure, 39/49 feet. With 202 trees to the acre — and there are 

 probably rather more than less — this gives the enormous total 

 of 10,150 cubic feet, or, by quarter-girth measure, 7,977 cubic 

 feet. 



No. 2. — Sample Douglas Fir, Measured 1903. 



No. of 

 Section. 



Length of 

 Section. 



Mean 

 Diameter of 

 Sections. 



Volume of 

 Wood in each 

 Section. 



Mean Cir- 

 cumference 

 of Sections. 



Volume of 

 Wood by 

 Quarter-girth 

 Measure. 



Feet. 



Inches. 



Cubic Feet. 



Ft. In. 



Cubic Feet. 



1 



2 

 3 

 4 

 5 

 6 



7 

 8 



9 

 10 

 11 

 12 

 13 



6 

 6 

 6 

 6 

 6 

 6 

 6 

 6 

 6 

 6 

 6 

 6 

 3 



17-52 

 15-29 



I3-54 

 12-66 



12-02 

 II- 3 I 



10-35 

 9*39 

 8-44 

 7-16 

 5-89 

 4*62 

 3*13 



10*04 

 7-64 

 6 - oo 

 5*24 

 473 

 4-19 



2-89 



2'33 

 i-68 

 1 -14 

 •70 

 •16 



4 7 

 4 0 

 3- 6J 

 3 3i 

 3 if 

 2 n£ 

 2 8£ 

 2 54 



2 2| 



i io| 

 1 6* 



1 2$ 



0 9l 



7-88 

 6 00 

 4-70 

 4-16 

 3'7i 

 3-37 

 273 



2-28 



181 

 1-31 

 088 

 0-54 



0'12 



Total ... 



75 





50-25 





39'49 



If the volume per acre be deduced from the equation — 



Volume per acre Sectional area per acre 



Volume of sample tree ~ Sectional area of sample tree' 



we get, Volume per acre = 1^327 = cu ^ c ^ eet ' 



Seeing that this was the method adopted by Dr. Schlich, we 

 may accept the last result for purposes of comparison. 

 Deducting the volume per acre in 1888 (3,738 cubic feet) from 

 the volume in 1903 (11,171 cubic feet) we get the lmost 



