THE EUCALYPTUS TREE 



673 



and timber cut from the heart is more du- 

 rable than sapwood. 



Blue-gum timber has been used to a 

 limited extent to determine its value for 

 railroad ties. The results thus far ob- 

 tained indicate that it compares favorabb/ 

 with second-grade pine-tie timber. 



The lumber has been extensively used 

 for vehicle stock and for the wooden 

 parts of agricultural implements. It is 

 also made into insulator pins for electric 

 wiring, and is used for furniture and 

 cabinet work, hardwood flooring, trip- 

 hammer beams, the levers of windlasses, 

 and the blocking for oil and wine presses, 

 wood paving, pulley blocks, and belt 

 wheels. 



The extensive utilization of gum lum- 

 ber has hitherto been prevented chiefly 

 by the scanty supply of timber of mer- 

 chantable size and by the difficulty expe- 

 rienced in seasoning the lumber without 

 warping and checking. It is believed, 

 however, that in the seasoning of gum no 

 greater difficulties will be encountered 

 than in the seasoning of any other hard- 

 wood of similar density and strength. 



The esteem in which eucalyptus tim- 

 ber is held in California is based upon 

 the exclusive use of blue gum. In Aus- 

 tralia, however, this species is considered 

 inferior in strength and timber value to 

 several other eucalyptus. Strength tests 

 of the timber of blue gum and other euca- 

 lyptus grown in California have sus- 

 tained this opinion. It is therefore prob- 

 able that eucalyptus are destined to enjoy 

 yet greater favor when these other 

 species become more widely used. 



A product of considerable importance 

 derived from blue gum is the oil distilled 



from the leaves. Eucalyptus oil is rec- 

 ognized as a valuable drug and is exten- 

 sively used by pharmacists and physi- 

 cians. 



In many valleys of California euca- 

 lyptus windbreaks are considered abso- 

 lutely necessary to insure the successful 

 production of crops. They have been 

 most extensively used to safeguard citrus 

 orchards from strong and destructive 

 winds in southern California, but they 

 are now being established also for the 

 protection of vineyards and orchards of 

 deciduous fruits, olives, and walnuts.. 

 The blue gum excels other species for 

 windbreak purposes on account of its- 

 height and the rapidity of its growth. 

 The tall shafts of the trees bend before 

 the wind and act as a cushion to deflect it- 

 upward over an orchard, whereas ordi- 

 nary windbreak trees form a more solid 

 wall, and the wind draws downward,. 

 forming eddies near the leeward side. 



Eucalyptus reproduce readily by both- 

 seeds and sprouts. The trees bear seed 

 in abundance annually, and under favor- 

 able conditions natural reproduction is 

 freely established. Trees also sprout 

 vigorously from both the' stump and the 

 roots, either after cutting or in response 

 to injury. In California commercial, 

 groves are almost invariably reproduced 

 by sprouts. 



Plantations should be started with 

 young trees and not by direct sowing. 

 The opinion is generally held that euca- 

 lyptus seedlings are so difficult to raise 

 that their propagation is impracticable 

 except for expert nurserymen. In point 

 of fact, blue gum is one of the most 

 easily propagated species. 



