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A very large part of the roots of the coconut grow in the stratum 
between 20 and 50 centimeters, and a tree to which water is available 
only at a greater depth must suffer. If conditions exist which permit 
roots to grow only at a greater depth, the obvious result will be a larger 
proportion in this deeper situation; in this way trees growing in dry 
places adapt themselves to their environment. However, trees which are 
compelled to adapt themselves to unfavorable conditions of any descrip- 
tion can not be expected to be prolific. This is well illustrated by the 
dearth of nuts on the Cocos-clad hills about Romblon and Masbate. The 
water which can be drawn from a dry soil contains a greater proportion 
of mineral substances dissolved in it than that which is available when the 
soil is wet, so that the proportion between the quantity of available min- 
eral food and the amount of water absorbed is not constant. 
The shoot suffers from the inactivity of the roots. The influence of 
the drought on the growth of the leaves, and on the action of the hinge, 
has already been shown. The leaflets, which under these conditions are 
more folded, absorb less light, so that the leaf area which the tree has at 
its disposition is less efficient in photosynthesis. A normally active tree 
produces from twelve to twenty-four or more leaves a year. After Decem- 
ber, during this drought, no new leaves appeared on trees which were 
less than 2 years old, and not more than one on any tree less than 5 years 
old. As a general rule, the older the tree the later it begins severely to 
suffer, the probable cause being that its roots run deeper than do those of 
the younger ones; but the growth of the leaves of individuals of all ages 
was very evidently retarded during February. This, in itself, would 
result in a decrease in the number of leaves borne at one time; but 
another factor is at least equally efficient in bringing about this result. 
The old leaves of the coconut are cast in a succession which, in adult 
trees, normally keeps pace with the appearance of the young ones, so 
that the number present at any one time does not materially vary. The 
internal factors causing the fall of the leaves have never been investigated, 
but there is no doubt that dryness is one of them. The “physiological 
dryness” caused by the outside drought naturally finds expression in a 
more rapid aging and falling of the leaves. . In fact, the first, and for a 
long time the only, noticeable symptom of dryness is the number of leaves 
pendant or falling. It has already been noted that trees without a 
rather indefinite minimum number (say, twenty) of leaves, have not the 
vitality which is necessary to ripen nuts. An individual with only ap- 
proximately this number will naturally not bear many. A retardation 
in the production of leaves and an acceleration in their loss, when acting 
together, will rapidly bring even the strongest trees toward this limit. 
The flowering branches are formed in the axils of the leaves, and the 
formation of fewer of the latter must in ifself ultimately result in the 
growth of fewer of the former. However, in practice, the development 
of these branches themselves is dependent, like any other growth, on a 
