PRINCIPAL SPECIES OF EUCALYPTS GROWN IN AMERICA. 69 



plains iind foothills, on the sides of low mountains, and in the warm, 

 dry interior valleys. It will make some growth in the poor soil of 

 hillsides, but prefers a fairly fertile soil. In Australia, according to 

 Mr. Howitt and Mr. Maiden, it grows on both lowlands and highlands. 

 Use.^.— The timber of the Yellow Box is very hard, tough, and dur- 

 able, but is difficult to work and is not easil}^ split. It is used in 

 Australia for spokes, rollers, heav}^ framework, naves, and cogs. 

 It is durable underground, and is consequently useful for telegraph 

 poles and fence posts. It also makes an excellent fuel. On account 

 of its profuse, fragrant ])]oom, it is comnig to he highly prized as a 

 source of honey. 



Eucalyptus microtheca. 



C'OOI.IHAH. 



Characteristics. — The Coolibah is a tree of medium size, generallv 

 more or less crooked, but of quite a pleasing appearance. The usual 

 height in Australia is 50 to 80 feet and the diameter 2 to 4 feet. The 

 few growing in America have quite erect trunks and give promise of 

 becoming fair-sized trees. (PI. XXXII.) It is one of the largest trees 

 of the interior desert regions of Australia. The bark of the trunk is 

 rough, generally furrowed, conmionly persistent, and of a ])rownish- 

 gray color (see PI. LXVIII); that of the branches, white and decidu- 

 ous. The wood is dark red or brown, and excessively hard and inlocked. 

 The foliage is rather dense and inclined to droop. The leaves are 

 long and somewhat curved, the two sides being e(|ually dull green. 

 The flowers are very small, in 3 to 8 flowered clusters, which usually 

 grow in groups. The seed cases are very small and broadly top- 

 shaped, w ith the valves protruding. 



Climatic requirements. — The tree is indigenous to the drj', hot 

 deserts of Australia, doing best in gravelly, well-drained soil. Baron 

 von Mueller saj's of it, in his Eucalyptographia, that it will " brave a 

 climatic temperature as torrid and as high as any on our planet, the 

 thermometer rising in the shade, in places where this P^ucalyptus 

 grows, occasionally to 127"^ F.'' In his Select Extra-tropical Plants 

 he states that it " withstands unscorched a frequent heat of 156^ F." 

 It also endures heavy frosts. It has grown well where it lias been 

 tried in the Southwest. 



Usex. — ^As a forest cover for excessively hot, dry regions in the 

 Southwest, this tree is quite a promising one. It furnishes a timber 

 that is valuable for bridges, railway ties, posts, and for general build- 

 ing purposes. On account of the color and markings of the wood 

 it is used for cabinetwork to some extent. The roots of this tree are 

 used in a novel way by the natives of Australia. In common with a 

 few other species of Eucalyptus this tree possesses water-yielding 



