1920.] Hutchins—Growth of Trees in Relation to Forestry. 3 
Table F purports to show the time required by various trees to reach 
1 ft. in diameter ; but the trees shown have grown under conditions so 
different that a comparison has little value. Most of the introduced trees 
cited belong to the light-demanding class grown in the open or in sparse 
forest; and these are compared with kauri grown as a forest-tree or grown 
in the open where the conditions are not favourable to it and where it 
often refuses to grow at all. * Thus the comparison is not valid. Quite 
commonly kauri growth-rings show that the sapling tree in the forest was 
dominated and occupied many years in slowly making its way through the 
dense under-forest. It is quite common to see kauri logs with an average 
of thirty to fifty rings per inch of radius at the heart, and only six to ten 
rings per inch of radius afterwards. 
Mr. James Stewart, famous for his study of the Auckland Domain native 
trees, relates in the Transactions of the New Zealand Institute , vol. 38, how 
a rimu planted in the Auckland Domain in 1865 and felled in 1904 had 
a girth of 3 ft. 9 in. By examining the growth-rings it was found that 
the tree had taken 12 years to reach a diameter of 2 in., but this was 
succeeded by a rapid rate of increase in the next 10 years amounting to 
J in. in diameter per annum. 
The popular quick-growing introduced trees, on the other hand, are 
generally those which grow quickly at first. I could take Mr. Maxwell 
to a tree-stump in the particularly fine eucalypt plantations of Mr. Davison, 
Culverden, Canterbury, and there show him the premier fast-growing gum- 
tree of New Zealand up to this time, Euc. viminalis, at fifty years of age 
growing at the rate of the average kauri-tree at the same age. Again, the 
Forest Commission Report of 1913 gave a figure of totara growth-rings 
intended to prove the slow growth of this tree. Sir W. Schlich analysed 
the photo and showed that the growth of the totara was slow only at first. 
In after-years it grew as quickly as the fast-growing Douglas fir. 
Further, the actual measurements on Mr. Maxwell’s table F are too 
diverse in their origin to be legitimately comparable. Foresters measure 
trees in one way, but timbermen, farmers, and amateurs in various ways. 
A cursory inspection of table F shows incongruities. Larch comes out at 
the bottom of the list ; but larch nearly always grows fast at first (the 
period treated in this table)—in many instances as fast as insignis pine. 
It is later that it fails. That is what one sees in the millions of larch 
unfortunately planted in the Government timber plantations. Such 
behaviour is to be expected with exotic trees put into too warm a 
climate : it happened in Europe 100 years ago with larch. 
Pinus Benthamiana and Pinus ponderosa, it may be noticed, figure in 
this list as two trees with different rates of growth. Actually they are 
the same tree under different names ! 
Table G is a continuation of table F, taking eucalypts only. Thirty- 
four species measured by eight observers (possibly in eight different ways) 
are thrown together, with all their varying qualities and rates of growth, 
and, as might be expected, they come out topsy-turvy. The quick¬ 
growing spotted gum ( Euc . maculata ) is at the bottom of the list, taking 
29-8 years to grow 1 ft. in diameter, while the slow-growing E. amygdalina 
is at the top, growing 1 ft. in diameter in 9-2 years. The slow-growing 
Euc. paniculata makes 1 ft. diameter growth in 13 years, while Euc. 
pilularis, the champion fast-growing gum of eastern Australia, takes 
