﻿AN ECONOMIC STUDY OF ACACIAS. 23 



this source of tanning material has been recognized for some time; 

 the planting of wattles would seem to offer a solution for the difficulty. 



POSSIBIilTIES OP GROWTH. 



There are enough trees in California to furnish seed ; and the growth 

 of individual trees has already demonstrated the fact that tanbark 

 acacias should be successful over large areas. On the Pacific coast 

 and in the Southwest there are many districts well adapted to tan- 

 yielding acacias; and there should be a market not only for the bark 

 but for fuel wood after the bark is removed. Even where, isolated 

 trees suffer from frost, groves of trees sheltering each other will not be 

 subject to the same damage. Acacia pycnantha, even when small, 

 has withstood the winters of Cholame Valley, Monterey County, in a 

 district where peach, cherry, and grape crops have been lost through 

 late frosts. 



While the amount of rainfall which acacias require seems not to 

 have been determined, it is generally assumed that 16 inches a year 

 is the minimum for Acacia decurrens. Yet deep-rooted saplings will 

 thrive on much less. The reports of the University of California 

 show that in the drought years of 1897, 1898, and 1899 acacias of 

 the leading tanbark species grew well with rainfall of from 4.8 to 8 

 niches. In Los Angeles Comity young trees set out in the spring of 

 1897, and thus subjected to three successive drought seasons, made 

 growths of from 4 to 6 feet in height a year, and in 1911 were 2 feet 

 in diameter. These and other instances justify the belief that some 

 of the best Australian acacias will thrive in America under almost 

 desert conditions. If they can be made to supplant large areas of 

 chaparral they will maintain a protective covering for the soil and 

 produce in addition a profitable crop. 



The increasing demand for tanbark Ought to direct attention to 

 these drought-enduring wattles. In California the native oak has 

 advanced in price from $6 per ton in 1870 to $48 at the present time. 

 Bark cutters are now forced to seek the most remote and rugged 

 canyons in Mendocino, Humboldt, and Del Norte Comities, and some- 

 times carry out the bark on pack mules. In the Mendocino forests, 

 once thought to furnish a practically inexhaustible resource, the 

 writer has seen the bark cutters stripping trees only 3 inches in 

 diameter. 



California has a large investment in the tanning industry, and 

 California leathers are shipped to all parts of the world, so that the 

 disappearance of the main source of tannin supply becomes a serious 

 problem. 



It should be possible to produce wattle bark for market on low- 

 priced land from cheap home-grown seed. While it is useless to 



