" AN ECONOMIC STUDY OF ACACIAS. 29 
Acacia salicina.—Stem diameter 15 mches; wood heavy, hand- 
some, dark brown in color; weight of cubic foot 47 pounds; takes a 
high polish; much used for furniture. 
Acacia stenophyllan—Stem diameter 20 inches. Wood very solid, 
close-grained, dark; takes a superior polish. Is called “‘ironwood,” 
and is much used by cabinetmakers. 
Acacia sub-porosa.—Stem diameter 18 inches. Wood extremely 
tough and elastic; used for wagon poles, tool handles, gunstocks; also 
for spars of coasting vessels. 
Acacia koa, of the Hawaiian Islands, has astem diameter sometimes 
2 or 3 feet and is considered the best timber tree of the islands. Its 
wood is easy to work, hard, handsome, in great demand for furniture, 
boats, and building generally. It grows at an elevation of 4,000 feet 
above the ocean. The few remaining forests of this acacia should be 
protected and young plantations established to supply future needs. 
The tree has not yet been sufficiently tested in California. 
Acacia catechu.—An even more valuable acacia.is Acacia cate-hu of 
India. Stem diameter 2 feet. The heart wood, which is more durable 
than teak, is not attacked by insects. The weight of this timber is 
-70 pounds per cubic foot, and it is used for pestles, crushers, rollers, 
and all sorts of wheelwrights’ work. 
Besides these 25 species there are about 20 more which have not 
yet been tested in the United States, but whose wood is highly valued 
in their native countries for beauty or durability. 
TIMBER ACACIAS IN CALIFORNIA. 
Few of the trees which have been cut in California for wood speci- 
mens have been more than 20 years old, nor have they had diameters 
ereater than 18 inches. Larger trees are usually so ornamental that 
owners dislike to cut them. But these older and larger trees would 
show a better quality of timber. Another thing that should be taken 
into consideration is that none of the timber species have been grown 
.in California under forest conditions. The specimens in Hough’s 
‘American Woods” were grown in Alameda County as park trees. 
In California, Acacia melanoxylon, the best of the timber acacias, has 
made a diameter growth of 18 inches in as many years, and trees 25 
years of age attain the height of 60 feet and a diameter, in some few 
cases, of as much as 30 inches. It is often planted as astreet tree, 
and its ability to thrive near gas works and manufacturing establish- 
ments, where nearly every other species of tree will perish, has already 
been commented upon. In Shasta and Amador Counties it has been 
noted that this acacia is markedly resistant to the fumes of copper 
smelting. In Oakland there are good specimens thriving on refuse 
dumps and in sewage. It will stand much surplus water, alkali, and 
