KAURI GROWTH-RINGS. 19 
PHoro oF Kauri Rives. 
Plate IV shows a 4-ft.-l-in.-diameter Kauri tree as cross-cut, with 
the yearly rings weathered and quite clear. They show a diameter- 
growth almost exactly four times the average of European timber-trees. 
Years. 
Average, as abové, five chief European timbers, per 
foot of diameter ate “th: u- ay ae 
Average this Kauri (as below) per foot of diameter... 28 
In this tree the ‘‘ dominated heart’’ shows rings averaging only 
gi In. broad. In the photo the dominated heart extends to the mussel- 
shell. 
When taking this photo I stuck on two mussel-shells to show 
what may be termed the business part of the diameter-growth. After 
2 ft. or 24 ft. of diameter the stem of a Kauri tree in a cultivated forest 
represents too high a capital value to leave uncut. Thus the part of 
the radius between the two mussel-shells on this photo indicates the part 
which can be grown economically. On this stem the dominated heart is 
represented by 3in. of radius. The economically valuable part of the 
radius is shown by the arrow on this photo, 1} ft. long. Here I counted 
84 rings, or 56 per foot of radius, or 28 per foot of diameter, along a 
radial length of 1}$ft., which means that the economical growth here 
was 1 ft. of diameter increase in twenty-eight years—an unusually fast 
growth. A few of the rings are as broad as tin. I have seen 4 in. rings 
on Kauri, and Mr. Cheeseman records rings up to lin. (Trans. N.Z. 
Inst., June, 1914, p. 18.) 
Favourable as is the growth of Kauri compared to other timber- 
trees in both thickness and height, there is another important point in 
the timber-growth of a tree—a third dimension! Here Kauri surpasses 
most trees and all giant trees with which it might be compared. The 
taper or form-factor of Kauri is discussed at page 48. 
While these pages were in the press Mr. Lane-Poole, the Conservator 
of Forests, Western Australia, wrote thus to the Lands Department, New 
Zealand, regarding certain specimens of New Zealand wood that had 
been sent to him by the Lands Department, Wellington: ‘‘ This sample 
(Kauri) has a mean diameter-growth per year of no less than 0°28 in, 
. This result is very much at variance with the accepted theory, 
which I think had birth in New Zealand, that Kauri is too slow-growing 
a timber to repay the cost of treating on a scientific forestry system.’’ 
MNEMONIC. 
In old trees the growth-rings show clearly 
That the five chief timbers of Europe 
Have but half the stem-thickness of Kauri, 
Nor in height do they come near our Maori! 
KAURI TIMBER. 
VALUE or Kauri Timper. 
Just because it was so abundant in the old days and New-Zealanders 
took no care of it, Kauri was used for various menial purposes—-for 
butter-boxes and packing-cases in Australia, and in New Zealand as an 
ordinary house-building timber. 
