PRINCIPAL SPECIES OF EUCALYPTS GROWN IN AMERICA. 61 



Uses. — The timber is strong and durable, splits readily, and is not 

 liable to warp. It is useful for lumber, for fence rails, and for posts. 

 The bark is used for roofing, for mats, and for strings. The leaves 

 are a source of Eucalyptus oil. 



Eucalyptus globulus. 

 Blue Gum. 



Characteristics.- — This species is the best known of the Eucalypts 

 and in many respects the best known tree in all the world. Baron von 

 Mueller says of it: "Of the more than 1,000 different species of trees 

 indigenous to Australia, Jiucalyptus globulus takes the first position 

 in importance, and among its own kind it is the prince of Eucalypts." 

 It is the third tallest of the species of Eucalyptus, the usual height in 

 Australia being 200 to 300 feet. In California, where trees can be 

 found 30 or more years old, many have attained the height of 150 

 feet, and a diameter of 3 to 6 feet during these years. One tree in 

 Pasadena, 25 years old, is over 5 feet in diameter. Trees set thirty 

 3 r ears ago along an avenue in Santa Barbara range from 3 to 5 feet in 

 diameter. (PL XXI.) There are many instances of these trees attain- 

 ing the height of 50 or 75 feet in from five to ten years. It is without 

 doubt the fastest growing tree in the world. It is friendly to new 

 conditions, and, taking all its characteristics into consideration, it is 

 the best all-round Eucalypt. It has been more extensively planted 

 throughout the world than any other Eucalypt and probably more 

 extensively than all other Eucalypts combined. The tree varies as to 

 its habit of growth, but is usually quite erect, though not always 

 symmetrical in form. By a continual flaking off of its bark in patches 

 or long strips it is left smooth and greenish or grayish in color. 

 Occasionally, however, trees are seen with the bark persistent, espe- 

 cially near or at the base. (PI. IV, a.) 



The leaves of the young seedling and of sprouts from the tree are 

 quite different from those of the adult trees. The earlier leaves have 

 a dusty, light-bluish coat, and are broad and opposite on the stems 

 (see PI. LXXXIII. c), while those of the adult are smooth and elon- 

 gated. The young twigs are four-sided, while those on the adult trees 

 arc cylindrical, or nearly so. The flowers are large and quite con- 

 spicuous. They glow singly or in clusters of 1 to 3. A prominent 

 characteristic of the flower bud is its rough, warty protuberances. 

 The seed oases arc large and nearly hemispherical in form. (See 

 PI. EX.) The seeds are larger than those of most of the species. 



Climatic requirements. — This remarkable tree has the power of 

 adapting itself to a variety of climatic conditions. It thrives both in 



moist, warm regions and in quite hot, dry ones. It makes a good 

 growth both in lowlands and in dry, stony uplands. Its powers of 

 removing stagnant water from low situations and of maintaining a 



