STATES KELATIONS SERVICE. 333 



Hawaii Station. 



The work of the Hawaii station proceeded along the general lines 

 previously described until the spriiiig of 1917, when the station en- 

 tered into an active campaign to bring about more adequate food 

 production and conservation. In this work, the station cooperated 

 with individuals and organizations of various kinds, and through 

 the combined efforts of ;ill agencies the supplies of locally grown 

 foods have been largely increased. 



The cooperative forage crop work at Schofield Barracks, begun in 

 1910, has been developed as rapidly as possible, about 50 forage and 

 food crops being under test. Over 100 acres of land at this Army 

 post has been cleared of brush, plowed, and planted to sweet potatoes 

 and cassava this year. 



The chemical work has been chiefly a continuation of investigations 

 on the control of pineapple troubles due to abnormal soil conditions. 

 The discovery, announced last year, that spraying pineapple plants 

 with iron sulphate corrects the injurious effect of an excessive man- 

 ganese content of the soil has been followed up, and more than 5,000 

 acres of pineapples was successfully sprayed during the year. Some 

 preliminary experiments for the control of a pineapple wilt indicate 

 that the application of lime to the soil will give relief. Work in 

 progress on the drying of certain products has shown that by ex- 

 posure in suitable containers cassava, sweet potatoes, taro, etc., can 

 be readily dried in the sun and wind and the resulting product stored 

 without apparent deterioration. 



In the horticultural investigations special attention is given to 

 pineapple breeding work, several thousand seedlings being grown for 

 testing. Some introductions of improved varieties recently made are 

 being tested in comparison with the standard variety grown in Ha- 

 waii. Similar work is in progress with mangoes, avocados, and other 

 tropical fruits. The station has produced several thousand seedling 

 tomatoes by crossing, and these are being given wide trial to determine 

 their immunity to pests. A blight-resistant potato thought to be an 

 accidental hybrid has been found which is being given a thorough 

 test for immunity, the plants on the station plats appearing almost 

 completely immune. 



The agronomy investigations are confined to experiments with rice, 

 taro, potatoes, leguminous crops, and forage grasses, much of the 

 work being conducted in cooperation with the military authorities. 

 Data already accumulated were of great value in the crop-production 

 work of the 1917 season and will be available so long as the emergency 

 continues. 



The plant-disease investigations have been largely confined to work 

 with potatoes, bananas, and celery, methods for the control of some 

 of the most serious troubles having been determined. Through the 

 extension division sprajdng campaigns have been conducted with 

 marked success. 



At the Glenwood substation, where the rainfall is heavy and the 

 temperatures comparatively low, special problems are being investi- 

 gated, the most profitable industry thus far developed for this region 

 seeming to be poultry raising. Dairying is also given attention, and, 

 with special methods of handling, some grasses and forage plants 



