AN ECONOMIC STUDY OF ACACIAS. 21 
grass covered and therefore required no clearing. Rows were marked 
at 12 feet apart and the seed was hilled 6 feet apart in the rows. 
Corn was grown between the rows for the first two years in order that 
its yield would help to reduce expenses. At 10 years old the trees 
were 10 inches in diameter. 
All the work on this 2,400 acres is done by 60 natives, who peel, 
cut, and dry the bark, stripping 1t at any season that it will peel 
easily. They use drying sheds of galvanized iron, each one of which 
holds about 6 tons of bark. | 
The gross receipts from 10-year-old trees at the price of $32 per ton, 
when Mr. Fairchild made the study, was from $161 to $193 an acre. 
The operating cost for harvesting the product was $7.30 a ton or 
$43 an acre. The 10 years’ care of the land, the cost of the land— 
in this case only from $5 to $6 an acre—and interest were said to be 
covered by the sale of the wood for mte props, fuel, and small timber. 
No replanting has been necessary, since thousands of seedlings come 
up and cover the ground. 
Another valuable publication on acacias in Natal has been fur- 
nished by “Mr. T. R. Sims;' but the most complete publication which 
covers the entire industry in 10 countries is the third edition of 
Dr. Maiden’s ‘‘ Wattles and Wattle Barks.” 
NORTH AFRICA. 
Johannes Paessler, of Levertechn, published in 1910 a paper on 
acacia bark grown in North Africa, in which he speaks of Acacia 
decurrens, decurrens mollis, decurrens dealbata, pycnantha, and pen- 
minervis. According to his report only the best species are planted 
and the tannin yield, which was less than 30 per cent, is now increas- 
ing. Acacia decurrens in German East Africa, at an elevation of from 
4,000 to 4,500 feet is ready for gathering at five years, and yields a 
bark of higher tannin content than that from Natal. At Freiburg 
Station 260 bark samples were analyzed by the filter method since 
1901, with the following averages: 
Per cent. 
TGS STEP TIS Ss Sees Ee, Ss de le a a a a 33 
Nontannins®= s2 22.2. eee ree ge ieee tes cree ee Ee he oo 8.5 
arse kin nles eececetey es cere ie ee tee PREAe Me Se ow oh oS: 43 
ihre rane etiee Sey Ge Ee Me tle cone eee gt ay Nt et 14.5 
There is a smaller proportion of nontannins to tannins in acacias 
than in the domestic barks, such as oaks. The sugar content is very 
low, which gives the acacias only slight acid-forming power. Ground 
acacia bark, according to this report, in Germany in 1910 cost $55 
a ton, which makes the tan worth about 84 cents a pound. 
1 “Tree Planting in Natal,’”’ Chapter 9: ‘‘The Black Wattle Industry,” Bulletin 7 of the Natal Depart- 
ment of Agriculture, Pietermaritzburg, 1905. 
