80 EUCALYPTS CULTIVATED IN THE UNITED STATES. 
Climatic requirements.—This species grows fairly well in quite a 
variety of situations in the coast region of California, but will not 
thrive in the dry, hot valleys of the interior. It will endure minimum 
temperatures of 18° to 20° F., and maximum temperatures of 110° to 
112° F., but it makes very slow growth under such trying conditions. 
Uses.—The timber of the Broad-leafed Ironbark, as of other Iron- 
parks, is strong and durable. It is used for bridge building, for posts, 
sleepers, railway ties, and for other similar purposes where strength 
and durability are desired. It makes a fair fuel, burning very slowly. 
Eucalyptus sideroxylon. 
Rep TRONBARK. 
Characteristics.—The Red Ironbark is a tree of medium to large 
size. It usually grows erect, with an even trunk, having numerous 
side branches, especially towards the top. It never grows to a great 
height. The bark is the hardest and darkest of the Ironbarks, the 
color usually being a dark red or brown. It is furrowed and cracked, 
and studded with beads of the kino that exudes from it. The whole 
appearance of the tree, with its rough, dark bark, its silvery, narrow 
leaves, and daintily colored flowers is quite distinctive, contrasting 
strongly with the smooth-barked, broader-leafed species of the genus. 
(Pl. XLV.) The wood is a dark red, and is very hard and heavy. 
The leaves are narrowly lance-shaped, often curved, and usually have 
a more or less evident silvery surface, the leaves of the seedlings being 
very similar to those of the adult tree. (See Pl. LXXXVI, 3B.) The 
flowers are somewhat above medium size, in clusters of 3 to 8. In 
color they vary from a light pink to scarlet. The covering of the 
flower-bud is cone-shaped, often sharp-pointed. The seed cases are 
nearly cup-shaped. (See Pl. LX XVIII.) 
Climatic requirements.—In Australia the Red Ironbark is most 
abundant on the stony, sterile portions of gold-producing districts, 
enduring considerable drought and heat. In California it thrives in 
dry soil near the coast, and on the plains and hillsides of many of the 
interior valleys. It endures minimum temperatures of 16° to 20° F., 
and maximum temperatures of 110° to 112° F., but makes a very slow 
and indifferent growth under such conditions. It has proven to be 
entirely unsuited to the hot, interior valleys of California and Arizona. 
Uses.—The Red Ironbark is one of the very useful Eucalypts. 
While the timber is not prized as highly in Australia as that of other 
Jronbarks, it is nevertheless valuable for many purposes. Its princi- 
pal uses are for bridge construction, for railway ties, for girders and 
large beams in buildings, for joists, for posts, for the hubs, spokes, 
and shafts of vehicles, and for a great variety of other purposes where 
strength and durability are required. On account of its shape and 
