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rubber, and what steps are practicable for minimising the injury caused 

 by them. In every form of cultivation the attacks of some animal or 

 vegetable pest must be looked for. As in places where men or 

 animals are crowded together diseases must be expected, so in plants, 

 when we take them from their normal isolated position in the forest 

 and put a vast number together without any separation from each 

 other, an essential of cultivation, we must expect disease of some sort 

 to make its way in. In the early days of cultivation, the planter was 

 content to take no notice of the pests of his plants till they forced them- 

 selves on his notice by nearly ruining the estate. But we have got 

 beyond that stage of early ideas and now realise that it is advisable 

 to attack a disease on its first appearance and keep it in check before 

 it gets unmanageable. The chief diseases of plants are due to attack 

 of fungi, as those of animals are due to Bacteria. In treating of fun- 

 gus pests generally we can most easily sort them into classes according 

 to the parts of the plant they attack, as the treatment of the disease 

 depends largely on this. Thus we may group them as ( I ) Root or 

 under ground Fungi, as Fomes. ( 2 ) Stem and bud Fungi as Diplodia 

 or Dieback. ( 3 ) Leaf-fungi as Helminthosporiun. The two last 

 being of course above-ground fungi. 



Now with the last class, Leaf-fungi, we need not trouble much, as 

 Para rubber being a leaf shedder is guarded to a large extent by the 

 falling of the leaves at intervals, from serious injury by the fungi of 

 this group. Any leaf attacked by a fungus falls soon and the progress 

 of disease is checked. It can never be as serious as the coffee leaf 

 disease which attacked the long-lived thick leaves of the evergreen 

 coffee. In Para rubber it is the root and stem diseases that are most 

 serious and to which it is important that attention must be paid. The 

 chief is Fomes semitostus. I suppose every one here knows the 

 fungus by sight, and knows too approximately its life history, as far 

 as that is known. I will give an account of its appearance in the 

 Botanic Gardens, as an illustration of the way it attacks. The ground 

 on which rubber trees had planted in about 1886, had grown to some 

 extent in secondary jungle, other trees had got mixed in, and these 

 had been cut out, their roots more or less removed. One day a care- 

 less cooly piled up some rubbish near one of the trees and fired it so 

 that two trees got badly burnt. I thought they would recover but they 

 did not, and fungus attacks destroyed them ; one of these fungi was 

 Fomes and this gradually spread through the adjacent trees, killing 

 them one by one on each side of the first injured ones. 



Now I call your attention to the fact that there had been old 

 scrub trees on the ground on which probably Fomes had been growing 

 and that the burning of the rubber trees started the outbreak. The 

 fungus attacked not dead, but dying trees. Is not this what practi- 

 cally happens in a new clearing We fell the forest and burn it. This 

 leaves just under ground, stumps of trees of different sizes in an inju- 

 red and slowly dying state. The Fomes common in all woods, is in 

 one of these trees and begins to develop on the dying stumps. The 



