STATES RELATIONS SERVICE. 335 



ticularly with a view to determining the relative efficiency of various 

 fertilizing constituents. A survey of the guano deposits of the island 

 was completed. Some work which has been begun to find the effi- 

 ciency of nitrate of soda and sulphate of ammonia for rice is of im- 

 portance in view of the possibilities of rice growing in the island. 

 Further biochemical investigations of chlorosis of plants are in prog- 

 ress. Comparative tests of nitrate* of soda and sulphate of annnonia 

 for })ineapples have given some striking results, but the experiments 

 are to be repeated before conclusions are drawn regarding them. 



The experiments with fertilizers for coconuts, which have been in 

 progress for several years, seem to indicate that yields may be largely 

 increased by the use of complete fertilizers, but there has thus far 

 been no increase in the size of the individual nuts. The work with 

 coffee and cacao has been continued and data regarding the crop ob- 

 tained. Leguminous shade trees have been successfully introduced, 

 'whicli So far have not been so subject to fungus and insect pests as 

 tliisi species commonly employed in shading coffee and cacao. The 

 station's work with vanilla has been so successful that it appears that 

 vanilla growing can be made a profitable industry. Arrangements 

 have been perfected for making several commercial plantings of 

 vanilla under the supervision of the station, and these, it is hoped, 

 will serve as demonstrations. 



The entomologist and the pathologist are continuing their investi- 

 gations of crop pests. Special investigations on the insects affecting 

 stored grains are in progress, and information regarding precautions 

 to be observed has been prepared and issued. Among the plant dis- 

 eases receiving attention are the banana wilt, citrus scab, bean rust, 

 tomato and potato blight, etc. Methods for their control are being 

 worked out. 



Following the station's work with forage crops and the introduc- 

 tion of improved breeding animals, the live-stock industry of the 

 island is making satisfactory progress. Extensive plantings of kafir 

 corn, Sudan grass, Napier grass, etc., which were introduced by the 

 station, are to be found in many parts of Porto Rico, and these crops, 

 as well as cane tops and velvet beans, have been successfully made 

 into silage. As a result, the cattle industry is thriving and dairying 

 has been widely extended, a great improvement in sanitary condi- 

 tions involved in the production and marketing of milk having re- 

 sulted from the station's demonstrations in handling this product. 



Guam Station, 



The animal-husbandry work of the station has been confined to in- 

 creasing and improving the station herds by the use of pure-bred 

 sires, producing improved sires for public use, finding the best 

 methods for taking care of different classes of live stock, and adapt- 

 ing pure-bred and grade animals to local conditions. The number 

 of horses w^as increased by the birth of one male colt during the past 

 year. No attempt will be made to enlarge the stud, as the station, 

 now has as many head of breeding stock as its resources will main- 

 tain. Several head of grade Ayrshire cattle were added to the herd 

 by births during the year, there being no losses. Three half-breed 

 Ayrshii-e-native bulls have been maintained in different localities for 

 free public service, Two of thes§ half-breed. buUs, pastu):ed on native 



