STATES RELATIONS SERVICE. 429 



water supplies as possible, particularly where the development of 

 additional water supplies does not seem possible. 



The activities of the horticulturist have centered on the acquisition 

 of improved fruits and vef^etables through introduction from other 

 countries and breeding work carried on with established varieties. 

 When the superiority of the new forms is definitely demonstrated, 

 the improved varieties are propagated for distribution, and during 

 the past year more than 20,000 plants of improved or promising 

 strains were distributed for a wide trial throughout the territory. 

 There is some evidence of the extension of the banana industry, 

 and the station has secured 26 varieties which are being tested in 

 comparison with the Chinese and Bluefields varieties, the only ones 

 that are now grown commercially. Papaya investigations have been 

 continued, and a method has been developed for producing lateral 

 branches that can be removed and rooted as cuttings. A number of 

 very satisfactory strains have been produced and given wide dis- 

 tribution. The use of papaya fruit for combining with pineapple 

 in the manufacture of food products has created a large demand 

 for this fruit, and special attention is given to soil and other re- 

 quirements of the plant. Variety tests of citrus fruits are being 

 continued, and several hundred seedling trees, grafted to a select 

 Kona orange, are being tested cooperatively by a number of grow- 

 ers. The work with mangoes, avocados, and other fruits is con- 

 tinuing as formerly. A number of valuable varieties have been 

 found, and some of them appear to be distinct horticultural acquisi- 

 tions. Experiments With coconuts have shown that germination 

 could be hastened by cutting off a part of the stem end of the husk 

 and burying the greater part of the nut in moist rice hulls. 



The work of the agronomist is concerned mainly with root crops 

 and forage plants. Among root crops, experiments have been begun 

 with some oriental root crops, such as arrowhead, and with the 

 water chestnut. Several forage plants new to Hawaii were tested 

 during the year, among them Guatemala grass {Tripsacum laxum)^ 

 Exophorus unisetus, four varieties of sorghum, and various le- 

 guminous crops. The latter were tested not only for forage but 

 also as green-manure crops. The importance of green-manure crops 

 to be grown in connection with pineapple production is becoming 

 well recognized, and special experiments have been begun along this 

 line. A hybrid between the Guam white corn and a variety of sweet 

 corn has been developed that promises to be valuable under Ha- 

 waiian conditions where common sweet corn does not flourish. Defi- 

 nite progress is reported in the production of a jellow strain of 

 Guam corn that will meet the common preference for a yellow corn. 



On account of quarantine regulations prohibiting the. export of all 

 fresh fruits except pineapples and bananas, experiments in the utili- 

 zation of surplus stocks have been in progress for some time, and the 

 chemist has devised methods for the manufacture of marketable 

 products of a number of Hawaiian fruits and vegetables. In con- 

 nection with increased banana growing, fertilizer experiments with 

 this crop have been begun, particular attention being given to the 

 times and methods of making the applications. Experience having 

 indicated that pineapples are best grown in rotation with some other 

 crop, a study of systems of cropping was made, and upland sugar 



