382 
roots of the planted rubber come into contact with those of the infec- 
ted stump and the mycelium spreads to the living root of the rubber 
covering it with its white strands and killing it, spreading from root 
to root. Where they are in contact it kills all the roots of the tree, and 
down comes the rubber tree. When the tree is dead or almost so the 
fruit, in the form of the well known yellow brackets appears and from 
the well known yellow brackets appears and from the under side of 
these are produced spores which can be carried by the wind to another 
injured tree and attack it. Now it is obvious that in a case like this 
the spore brackets could be destroyed even before they are ripe and the 
plant prevented from carrying on its destruction by spores and if this 
was the only danger from it, it would not trouble us much. The 
danger lies in the under ground mycelium which may be hid in the 
ground for some years creeping on the dying roots of trees and show- 
ing no signs of its presence till the death of a rubber tree is noticed. 
It is probable that by destroying the brackets before the spores 
are produced, continuously, that is to say preventing its reproducing 
itself by spores on the living trees, the mycelium would die out, that 
it could not go on indefinitely growing mycelium. But this is too 
slow and before this happens much damage may occur, and it is necess- 
ary to destroy the mycelium itself. We have attempted to do this by 
soaking the ground with bordeaux mixture, copper sulphate and lime, 
and by digging solid icopper sulphate and lime into the ground, but 
neither of these methods has had the desired result. This is due I 
think to the roots of the rubber being too deep underground for the 
liquid in sufficient quantity to soak in to reach the affected roots. An 
aid to cleaning infected ground lies in the use of bananas, or some 
such plant. The Fomes is unable to attack the roots of the bananas 
which aid by destroying with their roots the small dead bits which 
harbour, so to say, the mycelium. 
Liquid Fungicides. 
Failing any direct method of reaching the underground mycelium 
by Liquid Fungicides, the only thing that appears to be practicable 
is the thorough cleaning out of the ground of all stumps and dead 
roots of jungle trees. The mycelium I find remains on very small pieces 
of dead roots, in an active condition, and the ideal way to destroy it 
utterly, of course, would be to plough the ground thoroughly to expose 
and break up these little pieces, but this is I fear in the present state 
of our agriculture impossible. I have no reason to believe that the 
spores of this fungus can attack a Para rubber tree which is uninjured 
or even wounded say by tapping. I have seen the brackets in actual 
contact with living trees of different kinds, with no evil results. I 
believe it only attacks dying and decaying stumps at first and that 
its mycelium spreads along the roots in contact with the infected 
portion. In this way it can pass under paths, but deep drains seem 
to act as a barrier. There is much therefore to be said for blocking 
out the estate by good wide drains at no very great distance apart, so 
that if by accident the fungus should be in one block it cannot spread 
