Page:Tree Crops; A Permanent Agriculture (1929).pdf/187

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is rented by the tract, the cork is sold to contractors by the ton, the wood by the cubic meter, and the hog pasture on some lump-sum arrangement. Absentee ownership could scarcely be more providentially arranged. If you wish to see the Iberian owners of cork estates, go to Lisbon, Madrid, or Seville.

Every nine or ten, or eleven or twelve years, according to locality, the cork bark is stripped. An acre with a full stand of young trees should have seventy trees yielding fifteen kilograms per tree, or 2,300 pounds[1] per acre per stripping.

As the trees grow older and are thinned out to prevent crowding, the increased yield per tree keeps the cork output up to the average which, with care, can be maintained indefinitely at over a ton per acre per stripping. Cork is now worth about seventy-five dollars per ton. When the trees come down, they make the precious charcoal for the domestic fires beside which the Portuguese nation shivers in winters while it cooks its simple meals. In a properly cared-for forest every old cork tree has beneath its branches several half-starved understudies all leading a submerged life until it comes their turn to have space in which to spread.

I have seen a large cork tree, fifteen feet in girth and with a reach of fifty-six feet, that had yielded 1,980 pounds of cork at a stripping. An acre will easily hold eleven such trees, and I am told by competent authority[2] that there are many

  1. Consul General Lowrie at Lisbon reported (1913) the annual average cork production of the 900,000 acres of Portuguese cork forests was 240 kilos per hectare, 214 pounds per acre per year.

    The average annual yield of cork per acre in Portugal is put at 275 pounds per acre by the Quarterly Journal of Forestry, Vol. VII, No. 1, p. 57.

  2. Mr. John L. Wilson, an Englishman and educated as an engineer and for many years managing director of Bucknall Brothers, Lisbon, English owners of cork estates, cork merchants and manufacturers, reports one particular cork oak, the trunk twenty-four feet in circumference, seventy-two foot spread, which yielded at one cutting 2,112 pounds of cork; twelve years previously 2,310 pounds of cork, giving this tree an income value at that time (1913) of about one pound sterling per year from cork alone.