1919.] 



BOOT DISEASE OF CACAO IN TBINIDAD. 



179 



The section of the estate has recently been drained, and supplies 

 planted to replace missing trees. The state of affairs found is 

 represented in the foUomng diagram : — 



Hibiscus Hedge.— Dead. 



Q 



xxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxx xxxxxxxxxxxxxx 



s t. 



t T. 



t --t. 



D S. 



t t. 



t t. 



s t. 



D - 



T T. 



, T. 



T. Apparently healthy trees 



S. Sickly trees 



D. Dead trees 



— Missing tree 



t. Young supplies... 



4 

 3 

 2 

 1 

 9 



Total... ... 19 



Mr. Nowell examined the trees etc., and diagnosed the cause of disease 

 as Rosellinia Pepo which is described in detail later. 



The roots of the dead and dying hibiscus showed the smoky green 

 mycelium of the fungus (Fig 4.) The roots of the recently killed cacao 

 trees had the characteristic fans of white mycelium between the bark 

 and the wood. (Fig. 3.) Fruiting stages were found on the cacao and 

 also on the stump of an Immortel in the next bed which had also died. 



The following account of Eosellinia with special reference to its 

 attacks on cacao, is taken from the paper by Mr. Nowell referred to 

 above. The blocks of the illustrations have been kindly lent by Sir 

 Francis Watts, K.C.M.G., D.Sc, etc., Imperial Commissioner of Agricul- 

 ture in the West Indies. 



It should be noted that the disease is presumably not an introduced 

 one. The fungus which causes it is native to tropical America and the 

 West Indies, occurring in the forests, and is distributed by pieces of dead 

 wood with the fungus on them being washed down to low lying areas on 

 cacao estates. The disease can be got rid of by careful attention to the 

 measures recommended by Mr. Nowell (p. 189). The position is 

 therefore that planters have not a new disease to contend with, but now 

 know the cause of a disease of old standing and know also how to 

 eradicate it. 



The disease is however a serious one and neglected may lead to 

 severe losses. 



W. G. F. 



