KAURI ** GuM.”’ 37 
Resin-tapping may be looked at under four aspects :— 
(1.) Resin-tapping shortly before a tree is felled (gemmage @ mort). 
If properly conducted this can hardly possibly injure the timber, and 
there does not seem much chance of its doing so, even if badly conducted. 
(2.) I believe also that, employing narrower slits than the French 
practice (gemmage @ vie), resin-tapping will not injure the timber at 
any time. It is a point to determine just how wide the slits should be 
made, so as to let out the resin freely and at the same time prevent 
the entry of wood-borers, My experiment seems to show that the slits 
may be very narrow. 
(3.) There is another question: Will it improve the timber as it 
certainly does in France with Maritime-pine? 
(4.) And lastly comes the interesting speculation whether, if resin- 
tapping is done so as to exclude borers and fungoid rots, it may not 
promote a more vigorous growth of the Kauri tree itself. French forest 
officers have assured me that careful tapping actually promotes a better 
growth of their Maritime-pine. 
Function or REsIN. 
Resin-tapping invigorating.—lt is an interesting speculation whether, 
with moderate ‘‘ tapping,’’ letting off the surplus resin may not actually 
help the vegetative process of the Kauri tree. 
We know that the growth put on to the stem of a tree is formed by 
the descent of nutritive material from the leaves and boughs; that the 
boughs in Kauri trees after they have passed the “‘ricker’’ stage are 
very well developed; that in consequence the tree continues to grow 
rapidly at the base, and very rapidly in the part of the bole near the 
crown (this is shown by studying the rings). We know also that all the 
growing parts of Kauri trees are imbued with the resin, which is thrown 
off when and where the vegetative process is most active. Some trees, 
as most conifers, keep a good deal of resin in their timber, but many, 
especially non-conifers, throw it off altogether—the wild Mango, for 
instance, into its fruit. In many other trees and smaller vegetation, 
the bark, or leaves, or fruits taste strongly of resin, and this in situa- 
tions where the plant derives no benefit from its being there. It has been 
thought that resin was a protective secretion, but this theory is far 
from according with all the facts. It seems much more likely that resin 
is a by-product of the vegetative process, and that trees throw it off as 
soon as they conveniently can, At any rate, that seems to be the case 
with the Kauri» There is little or no resin in its timber; its bark is 
full of resin, which it gets rid of at every opportunity. The largest and 
most active of the resin-ducts seem to lie about the centre of the bark, 
which in Kauri is nearly all live bark. 
It is a fact in systematic resin-tapping that when it is first com- 
menced the trees respond to the tapping as if they liked it—the flow of 
resin gradually increasing for two or three years. If the resin-tapping 
be carried to excess the tree becomes injured in its growth, but will 
recover, unless the resin-tapping has been carried to great excess, the 
gemmage & mort of the French. But after all, this is the common effect 
of a tonic in medicine. I see no reason why light tapping should not 
act as a tonic to Kauri, encouraging a more vigorous growth. 
Thus, getting back to the French foresters’ theory, if some of the resin 
were removed the nutritive material from the boughs of Kauri might ~ 
descend more easily, and thus the growth be stimulated. At present. 
it is abnormally large near the crown, 

