APPENDIX. 



15 



Growth in heiaht and volume. 



Here a^aiti, to show the gain in volume, the graphic 

 method may with advantage be brought in. We will 

 bring forward here the eurvi; for height growth 

 whifh was th-st plotted, and draw on the same piece 

 of cross section paper the curve for volume, cubic 

 feet of contents being indicated on the right hand 

 vertical line. Ju comparison with height growth the 

 early growth in volume is seen to be e^ctremely slow. 

 At tifty jears of age, this tree is growing al)Out as 

 much wood as itdoesanj' thne later. Xo appreciable 

 shrink in its volume growth, however, is indicated, 

 as was the case in regard to heiglit. 



The tree, in fact, might go on to 200 or 300 years of 



age with an equal or greater volume increase. This 



would be gained mostly through growth in diameter 

 little gain in height would be made duriug the time. 



This tree, it will be remem- 

 bered, grew up on cleared land, 

 in fairly dense growth, among 

 coHjpetitors of equal strength. 

 Its history in respect to vol- 

 ume, as well as height, might 

 be considered normal for the 

 species, a spruce starting in 

 shade grows wood for many 

 years at an extremely slow 

 rate. Becoming free at length, S 

 a tree in natural woods ver3' '3 

 often is never afterwards s -i^ 

 crowded,so its volume growth ^ as 

 not only accelerates, but it u, 

 keeps on accelerating. That 

 is, it grows more wood when 

 it Avas 15 or 16 inches in 

 diameter than it did when it 

 was 12 or 13. Its curve in 

 consequence, keeps on mount- 

 ing at a faster and faster rate. 

 These points will be seen on 

 looking at the second set of 



HiSTOKY OF A TKEE'S 



Gkowth. 



.001 



.03 



.4 



1.1 



2.7 



5.0 



7.5 

 10.2 

 12.7 

 15.1 

 17.0 



Comparitively 



8« 9a loo lie 



10 xo QO Hb Stt 60 



Years of age. 

 curves that were given. For 

 tree No. 4, both height and volume curves were drawn. 



A book of 1000 pages could be tilled with facts of this description. 

 The present purpose is only to exemplifj' them and show how they 

 might be handled. There is, however, another set of relations which I 

 wish to develop from the original figures. 



