18 BULLETIN 9, U. S. DEPARTMENT OF AGRICULTURE. 
terminals of the former leaf-stalks, and occasionally they ay show 
on the younger erowth. 
The tree is less valuable for tannin than for timber; but a tree so 
large and rapid-erowing, the bark of which has a 15 or 20 per cent 
tannin content, should not be neglected in calculations for tannin 
production, especially since the development of the manufacture of 
tannin acid extract. A. melanoxylon properly belongs to moist and 
not frosty situations, and its roots are surface feeders. When young 
it is particularly susceptible to drought, and will die on soil the least 
bit arid; moreover, it succumbs readily to desiccating winds, such as 
the drying northers of California. Von Mueller reports it as being 
hardy (with some forms of A. decurrens) on the Isle of Arran, Scotland. 
This does not, however, prove the hardiness of the tree so much as 
it does the variation of local climatic conditions, since A. melanoxylon 
has been injured by frost (7° F.) at Chico, Cal.. It is useless to plant 
it in arid uplands, but its resistance to trying city conditions and its 
power of utilizing sewage make it of value as a street tree. 
TANBARK ACACIAS ABROAD. 
AUSTRALIA AND NEW ZEALAND. 
In Australia acacias have been utilized for tanbark for a long time, 
the natural su pphes being drawn upon exhaustively and the Trafic. 
culture of acacias consequently neglected, since there was an abun- 
dance of tan-yielding species on hand. 
Some 35 years ago, however, Baron von Mueller called attention to 
the rapid depletion of the natural supply, and from that time a volu- 
minous and important official literature upon acacias and acacia cul- 
ture grew up. Since 1875 these reports have aroused general as well 
as local interest in the planting of the species for tanbark. 
The three earliest and most careful estimates of “planting costs, 
based upon actual experiments in 1878, 1884, and 1889, give, respec- 
tively, the following figures: 
(1) Acacia Aacunnens, 100-acre basis, rented at $1.50 an acre a year, 
400 trees planted per acre: 
Avgerecate salesiof bark? first § years, 1)215tonss4. 2-2 s5085 94s eeeee $23, 290 
Agsregate expenses, includine interest:-<- 22255-4242." eee eee 7, 270 
Promt2s 233 oap5 caja bo ee eS See ce eee 16, 020 
(2) Acacia pycnantha, 100-acre basis, bought at $15 per acre; 1,200 
trees to the acre: 
Aggregate sales of bark, first: 7 years; 500 toms: 22-22 20s25 52 Soa ee eee $12, 000 
Aggregate expenditure, first 7 years, including interest............-..-.----- 8, 700 
| ETYGS i PS ReaM ae aa, Spe Ri relied Me Lins era ah scene arte E aeliebt ire lee nt ss 5 Ss 3, 300 
RETR 
Re ia aie 
