ENEMIES. 133 



I was told that it was nothing new, and that it was caused 

 by planting dadap between the Coffee plants for shade ; and 

 my experience since has convinced me that this is the case, for 

 wherever Coffee is planted in forest land, or where no dadap 

 trees are used for shade, there is no sign of leaf disease " 



and many other kindred " fads." High cultivation 

 and abundance of suitable manure are all that can 

 be recommended, with plentiful shade in the hotter 

 localities. Very possibly a succession of wet seasons 

 greatly tends to encourage the disease, for it should 

 be remembered that long-continued rain washes the 

 fertilizing matter of the soil into the subsoil and 

 therefore away from the reach of feeding rootlets; 

 while if a soil becomes water - logged, as it did 

 recently on many estates, the effect is to destroy 

 the nitrates present and evolve nitrogen as gas, 

 thus causing a very considerable loss of plant food. 



The rot shows itself most commonly in damp, 

 cold, upland plantations by the young leaves and 

 shoots of the trees turning black as though covered 

 with soot. Hull recommends draining the ground 

 and laying down mana grass two or three inches 

 thick over the surface. 



In Dominica the planters have suffered very 

 heavily from the larva of a small moth, Cemiostoma 

 co/eellum, upon which it is almost impossible to 

 wage effective war. 



In Fiji they have, especially on flats and Coffee 

 close to the jungle, a disease called " black leaf," 

 which is unknown in Ceylon unless " black rot" 



