Di 
THE VERTICAL GROWTH OF TREES. BE 
THEH VERTICAL GROWTH OF TREES. 
By R. H. CAMBAGR, F.L.S. 
[Read before the Royal Society of N.S. Wales, August 7, 1918.] 
THE point discussed in this paper in regard to the vertical 
growth of trees has no reference to the rate of growth, but 
deals only. with the question as to whether the trunk of a 
tree continues to lengthen among or below the branches 
while it increases in girth, or whether the increase in height 
is wholly due to the growth at the tree top. The question 
is one which has often been discussed, and opinions on the 
point are very diverse, but actual observations by means 
of experiments or tests appear to be few. 
lm regard to an Australian tree, testimony has been 
recorded by Mr. T. W. Fowler, . mst. c.2, who quotes a con- 
tractor of standing, as saying that a certain tree when 
first examined was about one foot too short to provide a 
twenty-foot beam, but twenty years later had increased 
sufficiently in length for the purpose. The species or kind 
of tree was not stated. 
Mr. District Surveyor W. G. Walker (ibid., p. 213), refers 
to an occasion, when some years previously, he saw some 
twenty-five year old blazes on trees growing on a low- 
lying rich flat on the Richmond River, and which were 
between two and three feet higher than those ordinarily 
made. The inference in this case was that the blazes had 
been cut at about three to three feet six inches above the 
ground, and in the subsequent twenty-five years the lower 
portion of the tree trunk had increased its length by about 
60 to 807%. In my own experience I have never noticed 
* The Surveyor, New South Wales, xvu, 187, (1904). 
