INSXJLAE EXPERIMENT STATIONS. 25 



most economical and effecti\e means of improving the productivity 

 of coffee plantations, diseases and insect pests, etc. Among the dis- 

 eases, a root disease, a leaf spot, and a spotting of the fruit have 

 received most attention. A trial of various adhesives to be added to 

 Bordeaux mixture to prevent its being washed off the foliage by the 

 torrential rains is in progi^ess. 



A number of coffee diseases of minor importance are being inves- 

 tigated, as are some of the fungus and other troubles of cacao, coco- 

 nuts, and bunanas. A bud rot of coconut trees has been found at 

 various places on the island, and while it destroys some trees each 

 year, yet the total loss appears small. Bacteria have been isolated 

 from the innermost dead tissues, but there has been a pronounced 

 lack of uniformity in the results of studies thus far carried on. The 

 diseases of citrus fruits have been taken up for study, especial at- 

 tention at this time being given to gummosis. It is expected that 

 cooperative work on orange scab and end rot of the fruit will also 

 be begun soon. The pathologist has made a study of the nodules on 

 the roots of the royal palm in the hope of elucidating some facts 

 regarding their origin and function. 



The station is actively engaged in interesting the people of the 

 island in apiculture. Demonstration classes in the handling of bees 

 were held at the station and they were well attended. Many of 

 those in attendance have purchased bees and are starting apiaries. 

 This industry appears to be increasing, and in connection with the 

 growing of citrus fruits and on coffee plantations the keeping of 

 bees should prove profitable, not only on account of the honey pro- 

 duced, but also by reason of the greater fertilization of the flowers 

 l)y the bee visitors. Attention is still given to the insects affecting- 

 citrus fruits, although less injury is reported than formerly. This 

 is due to the practice of establishing windbreaks about the orchards, 

 thus providing conditions for the development of beneficial fungi, 

 and to the use of sulphur sprays, which protect fruit against rust 

 mites. A number of pests of the mango have been investigated with 

 a view to discovering methods for their control. Studies were also 

 made of the coffee ant, insect pests of guavas, and mosquito breed- 

 ing. Contrary to the common belief, the entomologist found that 

 mosquitoes did not breed in the mangrove swamps about San Juan. 

 The horticultural work has been considerably extended, particular 

 attention being given to stocks, fertilizers, and cover crops for citrus 

 fruits. This work has been in progress since 1906, and it is hoped 

 to report on the work with fertilizers in the near future. Attention 

 is being given to varieties of citinis fruits adapted to Porto Kico. 

 Great variation has been noted in productivity, character of fruit, 

 etc., and data are being collected to determine the causes of this wide 

 variation. The station is conducting experiments on the introduc- 



