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COFFEE-LEAF DISEASE (HEM I LEI A VASTATRIX, B. ET BR.) 



IN UGANDA. 



By S. SIMPSON, B.Sc., 

 Director of Agriculture, Uganda. 



WITH A NOTE ON THE PRESENT POSITION 



By W. SMALL, M.A., B.Sc., 

 Botanist to the Department, 



[ABSTRACT.] 



Coffee may be said to be indigenous to Uganda, as the early 

 explorers mentioned its existence and large numbers of coffee 

 trees (Coffea robusta, Lind.) are scattered throughout the 

 Buganda Province. 



There can be no doubt that coffee-leaf disease has been 

 present in the country for many years, but was thought to be 

 something else. 



Later work on the subject has been done, and the examina- 

 tion of a large number of type specimens undertaken, so that 

 the fact is now established that there is no record of coffee 

 being attacked by any species of Hemileia other than 

 H. vastatrix. 



The treatment undertaken was picking and burning the leaves 

 and spraying plants with Bordeaux and Burgundy mixtures. 



So far spores of Hemileia from leaves of Coffea robusta 

 Lind. have failed to infect leaves of cultivated coffee. 



Transport of Hemileia spores is easily accomplished by 

 natural agencies such as the wind, but largely by the labourers. 

 The drier weather of 1913 arrested the progress of the disease, 

 and many estates which were severely ravaged are now show- 

 ing masses of fresh new foliage, new shoots, and prospects of 

 good crops. 



Again, the disease being endemic cannot be expected to 

 work the havoc that it wrought in Ceylon. 



Experiments with sulphur and lime as powders and various 

 solutions of salt and lime used as a spray have been disappoint- 

 ing. Up to the present Bordeaux and Burgundy mixtures 

 have given the best results. 



The behaviour of Hemileia is essentially that recorded from 

 other parts. 



A search has been made for a possible Aecidium condition, 

 without result. 



At least ten genera of the Rubiaceae occur in the Victoria 



