22 BULLETIN 9, U. S. DEPARTMENT OF AGRICULTURE. 
HAWAT. 
Prof. Jared C. Smith has made a full and careful report of experi- 
ments with black wattles in Hawaii.’ In this he states that acacias 
have been grown in the Hawaiian Islands for about 40 years, thriving 
on heavy soils with a rainfall of from 80 to 150 inches. The remark- 
able fact in connection with this exceedingly heavy rainfall is the 
adaptability of the acacias to various conditions from drought to 
deluge, and points to their possible use in such locations as the 
Colorado River bottoms and along the Gulf coast. 
Six acres of 13-year-old trees yielded $254.84 per acre. The bark 
brought about $139 (5.9 tons at $22.31 per ton). The wood sold for 
fuel yielded about $114. 
Aceording to Mr. Smith, one man with good tools and a team can 
take care of 250 acres of black wattles with ease when it has once 
been sown and thinned. ‘“‘One pound of good seed should plant 
10 acres.’ This illustrates scientific progress, simce many planters 
have been in the habit of sowing 5 or 10 pounds to the acre. Yet 
Acacia pycnantha has about 23,800 seeds to the pound; A. normalis, 
about 28,500, and mollis 38,500. The present Australian practice is 
to sow from one-third of a pound to a pound of seed an acre, but since 
1,200 trees is an abundant stand and 800 is better, a pound of good 
seed should sow 10 or more acres. In the famous Tantalus acacia 
plantation in Hawaii, the trees of 13 years vary from 6 to 18 inches. 
A 10-year-old tree would yield 100 pounds of green bark, which is 
equal to 50 pounds dry. The best trees yield as much as 200 pounds. 
TANBARK AcAcTAS IN CALIFORNIA. 
While there are no commercial plantations of tanbark acacias in 
the United States, the leading tanbark acacias have long been grown 
at the California Experiment Station at Berkeley and at various sub- 
stations. Their product has been analyzed and compared with that 
from the California oaks and from canaigre (Rumex hymenosephalus). 
In the bulletins of the California Experiment Station and of the 
Federal Forest Service? attention has been called to the rapid disap- 
pearance of California tanbark oak (Quercus densiflora), the tannin 
from which has given high reputation to California-tanned heavy 
leathers. The constantly increasing cost of the bark has been noted 
and at the same time the deterioration of its quality, since mere 
bushes and saplings are now being stripped for the thin young bark, 
incomparably inferior to the old thick bark from the boles of mature 
trees. The necessity of securing a supplement to or substitute for 
i Bulletin 11, Hawaiian Experiment Station, 1906, ‘The Black Waitlein Hawaii.”’ 
2 Bulletin 75, Forest Service, U. S. Department of Agriculture, California Tanbark Oak, by Willis Linn 
Jepson, issued Sept. 20, 1911. 
