erally considered sensitive to strong winds in California, but 

 in Hawaii it is found to grow straight and of good form even 

 in the most exposed situations. 



The eucalypts, as a rule, prefer a very moist soil and respond 

 readily to irrigation on dry situations. Swampy land, however, 

 is not favorable to good growth, especially if the roots of the 

 trees are constantly flooded. The red gum (E. ro strata) is 

 probably the least exacting in this respect, and will thrive in wet 

 swamps. Swamp mahogany (E. robusta), blue gum (E. glob- 

 idus), and the bastard mahogany (E. botryoides) will also en- 

 dure excessive moisture. The sugar gum (E. corynocalyx}, on 

 the other hand, is the most intolerant in this respect. 



Soil 



Unlike agricultural crops, trees are not fastidious as to the 

 quality of the soil on which they grow. There is hardly a soil 

 so poor as not to be able to support some tree growth. The 

 chemical composition of the soil is of little importance, provided 

 its physical composition is favorable. The physical composition 

 of the soil is important because it determines to a large extent 

 the amount of available soil moisture. A deep, loose, moder- 

 ately fine-grained, sandy loam is the best for most species of eu- 

 calypts, as it is for almost all other forest trees. 



The following trees require good soil for their proper growth : 



Blackbutt (E. pihtlaris), red gum (E. rostrata), manna gum 

 (. wminalis). 



The trees which are least fastidious as to their soil require- 

 ments are peppermint gum (E. amygdalina), yate (E. cornuta), 

 red mahogany (E. resinifera), swamp mahogany (E. robusta), 

 and red ironbark (E. sideroxylon) . 



HABIT OF GROWTH. 



Form and Size. 



There are two general classes of eucalypts recognized in Aus- 

 tralia, the tall timber trees, collectively known as "gums," and the 

 scrubby species, known as "mallees." There is no reason for 

 planting the mallees in this country except for forest cover and 

 water protection, and even for this purpose some of the faster- 

 growing gum trees would be preferable, both because of their 

 more rapid rate of growth and because of their greater value. 



As a rule the timber eucalypts, when grown under forest con- 



