72 

 OBJECT. 



The purpose of the Ewa Forest Reserve is to insure the con- 

 tinuance of the forest on the Koolau Mountains and to increase 

 its efficiency as a protection forest by bringing the area under a 

 system of forest administration. 



GENERAL COXSIDERATIOXS. 



The Ewa Basin contains some of the most productive land in 

 the Territory. The cane fields of the three large sugar planta- 

 tions of Ewa, Oahu and Honolulu, together cover an area of a 

 little over 20,500 acres. In 1905 70 per cent, of the sugar pro- 

 duced on Oahu, or 20 per cent, of the entire output of the Terri- 

 tory, came from these three plantations. The figures for the two 

 preceding years are only slightly different; the yield in 1904 

 being 66 per cent., in 1903 69 per cent, of the Oahu output — and 

 of the total Hawaiian crop, 18 per cent, for 1904 and 19 per 

 cent, for 1903. 



All of this great and productive area of sugar land in the Ewa 

 Basin is dependent on irrigation, for sugar cane cannot be profit- 

 ably grown on this part of Oahu without an abundant supply of 

 water. 



The water for irrigation comes in part from streams rising in 

 the Koolau Mountains and the Waianae Hills, through the di • 

 version of the natural flow and the impounding of storm water, 

 and in part from artesian wells. The greater part of the surface 

 water is developed on the Koolau, rather than the Waianae side 

 of the Basin, and although the geology of Oahu has not yet been 

 fully worked out, it appears that the water-bearing strata tapped 

 by the artesian wells also depend largely for their supply on the 

 precipitation on the Koolau Mountains. 



It is therefore important that as much as possible be done to 

 preserve and protect the forest on this important watershed. If 

 the steep slopes of the Koolau Mountains are covered w^th vege- 

 tation much of the water falling as rain can be retained for pos- 

 sible use, whereas were the slopes bare, a large share of the pre- 

 cipitation would escape as flood water, not only evading its duty 

 and being lost to use, but doing damage along its course as well. 



