the necessity for the operation. Divergence o

on. At the other extreme there is the opinion that we should plant only a few more trees per acre than it is intended eventually to maintain, the argument being that b

ng capacity. It might thus follow that a stand of ninety well-grown trees per acre might give very disappointing yields per acre. In a few i

vely high-yielding strain. This is a very sound argument, but its practicability is limited very largely by the question of early growth and development. It would seem the san

ng thinning proper can be commenced. In the past this has been effected wholly by selection of trees according to their general ap

have been advocating for years without much practical success. In Java and Sumatra much good

oung Plan

ginal jun

s, and that such trees are not to be distinguished by size or general development. Moreover, with slight varia

ed for the first round of thinning. It is found in actual practice that five, or even three, readings during the year are sufficient to give the indication required. It is

tex is measured by means of a thin slip of

easure gradua

e of a Recentl

, or ounces, as long as the unit is not too large. It is preferable to employ a fairly small unit, so that in taking readings from

the field to be tested, and to prepare a rough register, w

taught the method of measuring and rough recording. The latter is accomplished by means of marks made upon the virgin bark of the tree above the tapped area. The mark

e case of young trees) and following the course taken by the tapper, the measurer of yields is abl

y case this is immaterial as, owing to the personal equation of the tapper, comparison strictly should be limited and int

ced in the hands of a European. The register is taken into the field and the ro

ween the yields of individual trees, but they would probably

a young field from which all ill-grown and deformed trees had been removed. It is immaterial what the units

ex to reach the first mark were registered at

3 per

mark

2

3

4

5

6

7

8

9

0

minate between good yielders and others, and if thinning were to be done on the usu

er proportion the majority lie close to the datum line. It will be seen that there are outstanding yielders even amongst these young tr

hinning had been done previously on empirical lines. Sufficient has been written to show that the only reasonable basis for selection of trees in thinning is that of yi

over all trees is 6 lbs. Keeping in mind the test-figures on a previous page, it will be obvious that some of these trees may have given very much more than 6 lbs. during the year, and some less. In view of present information it would not be surprising to find that a few might have been yie

ung Area, just re

Tap

ans of propagation based on bud-grafting and marcotting, it needs no great stretch of imagination to forecast future conditions under which trees may be bred whic

er Trees in which

ed to

d comparative

tain cases where the soil is admittedly poor, the average growth below normal, and thinning has been postponed too long, the writer has been forced to the conclusion that it would be most inadvisable, and commercially unsound, to reduce the stand of trees below 120 per acre. In such instances the average

te that thinning was undertaken on almost purely empirical lines-i.e., that trees were not selected by tests of individual yields. As far as such a method retained the apparently

s appear to be fairly uniform in yields the first thinning must be confined to comparatively few trees. Where there is, on the other hand, a good percentage of high-yielding trees the fin

ideration one must pay no attention to symmetry of spacing, but when dealing with trees of fairly uniform yields one needs to study the characterist