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 cabi- 

 network, hardwood flooring, trip-hammer beams, the levers of wind- 

 lasses, and the blocking for oil and wine presses, wood paving, pulley 

 blocks, and belt wheels. 



The extensive utilization of gum lumber has hitherto been pre- 

 vented chiefly by the scanty supply of timber of merchantable size 

 and by the difficulty experienced in seasoning the lumber without 

 warping and checking. It is believed, however, that in the season- 

 ing of gum no greater difficulties will be encountered than in the sea- 

 soning of any other hardwood of similar density and strength. 



The esteem in which eucalyptus timber is held in California is 

 based upon the exclusive use of blue gum. In Australia, however, 

 this species is considered inferior in strength and timber value to 

 several other eucalypts. Strength tests of the timber of blue gum 

 and other eucalypts grown in California have sustained this opinion. 

 It is therefore probable that eucalypts 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 recognized as a 

 valuable drug and is extensively used by pharmacists and physicians. 



In many valleys of California eucalyptus windbreaks are consid- 

 ered absolutely 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 vine- 

 yards 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 ordinary windbreak trees form a more solid 

 wall and the wind draws downward, forming eddies near the leeward 

 side. 



Eucalyptus windbreaks planted every quarter mile across level 

 country will give effective protection. Near the foothills the belts 

 should be planted closer, since winds blowing down from the moun- 

 tains gather greater velocity. Through orchards they should gener- 

 ally be planted at intervals of about 200 feet. Where winds are very 

 severe, double or triple rows of trees should be planted. The best 

 spacing of blue gum trees for protective planting is 4 feet apart each 

 way. In double rows the trees of one row should be planted opposite 

 the center of the spaces in the other. The most effective windbreak 

 protection is secured by a combination of Monterey cypress and blue 



[Cir. 59] 



