28 REPOET OF OFFICE OF EXPERIMENT STATIONS. 



The plant pathologist studied the diseases of a number of eco- 

 nomic plants; among them were those occurring on coffee, cacao, pine- 

 apples, citrus fruits, sugar cane, and bananas. It has been found 

 possible to control the coffee-leaf blight by spraying just before the 

 beginning of the wet season. Experiments are in progress looking 

 to the control of the coffee disease due to Stllhunb fiavidum. The 

 effect of trenching about trees to prevent the spread of a root disease 

 is being tried. The experiments on soil disinfection for the preven- 

 tion of the Fusarium on pineapples have been so successful that the 

 treatment on a field scale was made during the past year. Experi- 

 ments have shown that spraying with Bordeaux mixture can not 

 be depended upon to control citrus scab in Porto Eico, as is claimed 

 to be the case elsewhere. A study has been begun on the fungi 

 causing root injuries to sugar cane, in which the fungi have been 

 isolated and as far as possible identified. A disease of bananas, 

 apparently due to a species of Fusarium that enters the plants 

 through the roots, is under observation. It has given little trouble 

 until the present year, and studies of methods for its control have 

 been beffun. A bud rot of coconuts has been found in a few locali- 

 ties, and as a somewhat similar disease is very destructive elsewhere 

 in the West Indies it will be given attention. 



The work with coffee, in addition to the experiments in the renova- 

 tion of old plantations and establishment of new ones, includes in- 

 vestigations with foreign coffees, methods of transplanting, viability 

 of coffee seed and means for preserving it, methods of fertilizing and 

 cultivation adapted to different types of soil, etc. Among the foreign 

 coffees introduced by the station a number of trees have borne and 

 the station has limited quantities of seed of Padang, Maragogype, 

 Preanger, a Ceylon hybrid, and the famous Blue Mountain coffee 

 of Jamaica that may be had for planting purposes. These are among 

 the highest-priced coffees of the world, and 3-year-old trees have 

 yielded over a pound of cleaned coffee to the tree. The work with 

 coffee will be considerably extended. Severe windstorms caused 

 many of the coffee berries to fall from the trees, and as a result 

 the crop was considerably less than it otherwise would have been. 

 Experiments have been begun on the value of windbreaks in con- 

 nection with coffee planting, and some of the species planted are 

 ready for testing. The result of the renovation experiment of the 

 old plantation for 1910 showed a production of 260 pounds per 

 acre, the cost of which for the year was $5.^5 per hundred pounds. 

 Practically all the seed produced on the new plantation was dis- 

 tributed for planting or used in testing, and no financial statement 

 for the year is possible. 



The horticulturist devoted much attention to a study of some of 

 the problems of citrus fruits, as that industry is developing quite 



