48 



essentially a wound parasite whether the wound which affords the 

 place of entry is associated with the attack of another fungus such 

 as those just mentioned or Corticium or whether the wound be 

 caused by a dead twig or broken branch. However the entry is 

 effected the hyphae begin to spread downwards in the tissue in the 

 young wood or young bark, that is near the position of the cambium, 

 killing the tree in a characteristic manner. It has generally been 

 my experience to find groups of trees affected together, usually 

 small groups. 



On one estate I recall an occasion on which 150 trees of seven 

 years old were found affected in one group. A few of these trees, 

 not more than six, were killed but many of the others had to be cut 

 back below the fork. Usually one tree is found killed and a 

 group of trees in the immediate vicinity more or less seriously 

 affected. 



The only method of treatment is to cut down all trees killed by 

 the disease and to remove all affected branches of trees which have 

 not suffered so severely. However slight the attack the affected 

 parts must be removed. All attacked parts of trees should be 

 destroyed by fire immediately. It is necessary to act immediately 

 when dealing with this disease as it develops and spreads down the 

 tree with great rapidity. Dead rubber trees and branches should 

 not be allowed to remain lying about in plantations. Any part of 

 a dead rubber tree affords a most suitable place for the development 

 of the fungus and indeed it can almost invariably be found on dead 

 rubber branches or stems. 



During the time I have worked in Malaya I have not been able 

 to find the stage described by Bancroft as the ascus stage in the life 

 history of the fungus which he considered to be the higher stage of 

 Botryodiplodia and for this reason re-named the fungus Thyridaria 

 tarda. There is no confirmation of the existence of such a form and 

 until Bancroft's work is confirmed Botryodiplodia theohromse as a 

 name has the prior claim. 



Phyllosticta ramicola and Gloeospormm albo-ruhrum. 

 For the purposes of this paper these two fungi may be dealt 

 with together as they are frequently intimately mixed on the same 

 affected branch or twig. The two fungi are parasitic and usually 

 affect the uppermost twigs which still have a green epidermis or 

 skin — that is, where cork has not yet been formed. 



Phyllosticta genei*ally makes its attack at a point 6 to 18 inches 

 below the apex of the shoot. When first noticed a brown patch may 

 be observed which later spreads upwards and downwards killing the 

 twig. Usually the fungus spreads no further down than two to three 

 feet below the apex. Gloeosporium has a similar mode of attack. 

 It is usually immediately after wintering when the leaves are just 



