DISEASES AND PESTS 35 



fungi (Fomes), which are parasitic on the trunks in the 

 Philippines. These doubtless do some injury to the 

 tree ; and this will probably prove to be true of various 

 others. Up to the present time, however, only four 

 species are positively known to be destructive, and 

 our knowledge of these is very recent. One of these, 

 Pythium, will be taken up in discussing the bud rot. 



Thielaviopsis ethacetica. — This fungus causes the 

 bleeding diseases of coco-nut trunks in Ceylon. It 

 usually shows itself at a height of 2 metres, more or 

 less, above the ground. It is described by Petch, in 

 papers read before the Ceylon Agricultural Society, as 

 follows : 



A brown liquid oozes out through the cracks in the cortex, 

 and forms a rusty patch which usually turns black afterwards. 

 On cutting into this patch, the internal tissues are found to be 

 discoloured and decaying ; they are brownish and finally turn 

 black. If the diseased area is cut in wet weather, the liquid 

 sometimes squirts out ; in fact, it may in some stages be 

 collected in a glass by simply pressing on the diseased patch. 

 After some time other black patches appear on the trunk, 

 usually on the same side. When this happens, it will generally 

 be found that this is not a new infection, but that the disease 

 has worked up or down inside the stem, and the liquid has 

 found a new outlet. I have seen trees which looked as if a 

 bucket of tar had been poured down one side of the stem. It 

 is important to note that there is no sign of the disease until 

 the liquid oozes out, and that when this occurs the internal 

 tissue is already decayed to some extent. 



In about two or three years the hard outside of 

 the trunk falls away. The crown gradually becomes 

 smaller ; and the roots wither more or less completely 

 at a depth of about a metre. The tree may die in five 

 or six years, sometimes more quickly. 



Young bearing trees, up to say twenty years, are 

 most susceptible. Very old trees are attacked, but 

 comparatively little injured. The disease occurs on all 

 soils, swampy, sandy, or rocky, manured or not, near 

 the sea, and inland. 



"With regard to treatment, Petch says : 



