24 



is found eventually that the spacing is too close the stand may 

 be thinned and the trees cut used for fuel or for other purposes. 

 On the other hand, if it is found that the trees have been planted 

 too wide apart, it is difficult, and often impossible, to plant ad- 

 ditional trees and make them grow in the shade of the trees al- 

 ready established. It is better to plant a small area properly 

 than to spread an insufficient number of trees over a large area. 



While it is risky to lay down hard and fast rules, the follow- 

 ing general guide may be used in spacing blue gum. 



Trees on good soil and in favorable situations can stand wider 

 spacing than groves on poor soils and grown in unfavorable 

 situations. 



For a windbreak or shelter belt, plant the trees 3 to 5 feet 

 apart, depending on the width of the belt. 



For the production of clear lumber and good quality of tim- 

 ber, plant the trees 6 by 6 feet apart. In especially windy situ- 

 ations or in very poor soils the spacing may be 5 by 5 or 5 by 6 

 feet. 



For the production of fuel, plant the trees 6 by 8 or 8 by 8 

 feet. 



For sheltering cattle from the hot sun or from wind and cold, 

 space the trees 9 by 9 or 10 by 10 feet. 



When undergrowth is dense and it is desirable to get rid of 

 it, plant the trees 5 by 5 to 5 by 6 feet. 



For watershed protection, plant the trees 6 by 6 or 6 by 8 feet. 

 If the trees are to be underplahted by a shrub, they may be spread 

 8 by 8 or 8 by 10 feet. 



TENDING THE GROVE. 



Fertilising, Irrigating and Cultivating. 



In their seedling stage almost all the eucalypts respond readily 

 to soil fertilization and cultivation. In a particular plantation at 

 Waipio, Island of Oahu, at an elevation of 1,000 feet, blue gum 

 (E. globulus) eight months old showed a maximum height 

 growth of 20 feet, while ten other species of eucalypts growing 

 on the same plantation and treated in the same way all showed 

 greatly stimulated growth as compared with the same species 

 growing on an adjoining plantation, apparently under similar 

 conditions, but not fertilized and not cultivated. Stable manure 

 is the best for this purpose, though ordinary commercial fertilizer 

 similar to the kind used in cane fields and pineapple plantations 

 can be used with great advantage. It is very doubtful, however, 



