A prehistoric squirrel, it is said, could have scampered
from Norway to Singapore without touching the ground, so dense was the carpet
of trees that stretched across the world. Similar forests stretched across
North America and many other parts of the world – all of them providing a home
to thousands of living things, all of them vacuuming the carbon dioxide from
the air and keeping the climate stable.
Most of that landscape was felled for timber and paper long ago, the land given
over to crops and suburbia – or to wasteland. Of course, humans need food and
houses, but we also need timber and wildlife, and our ancestors would have been
wiser to preserve some of those forests for future generations. And sometimes,
they did – for at least six thousand years, some humans have used an old
technique to continually harvest timber from a forest while keeping it alive
indefinitely.
When the evergreen trees around here are cut at the base, their roots die. But
many broad-leaved, deciduous trees continue to soak up water and nutrients
through their roots. The roots put their energy into creating shoots, which
grow into new saplings – and soon you will have several smaller trees where you
had one before. In a matter of years or decades – how long depends on the type
of tree – you can harvest those smaller trees, called “underwood,” and the
process begins again. You can keep doing this as long as the original base
continues to live, which can be more than a hundred years.
Commonly coppiced species included ash, chestnut, oak, hazel, sycamore and
alder, and most of these created shoots from the cut stump, called a stool. The
new trunks usually curved outward from the original stool, and so their
naturally bowed wood was often prized for ship-building. Other species, like
cherry, would send suckers upward from the roots surrounding the stump. Either
way, the new shoots grow quickly, fed by a root system made to support an
entire tree.
Willow stands in a class by itself in coppicing, as it does not need to mature
before being cut, nor does it require a decade or two of waiting. Its flexible
shoots – withies – are perfect for weaving into shapes, which provided early
humans with homes, boats, chariots, armour, fences, barns, sheds, coops, weirs,
animal traps, and baskets.
Woodsmen coppiced areas where they could keep out cattle and horses, as animals
might eat the shoots. In places where animals might roam the woodland they
would pollard – or cut branches higher up on the tree out of their reach. Waterford
farmer and self-sufficiency expert John Seymour called coppicing and pollarding
“the most fundamental of woodland crafts.”
In medieval Europe vast stretches of woodland were coppiced
or pollarded regularly for charcoal, firewood, timber and other uses. Here in
Ireland, willows – sometimes called sallies or silver-sticks – were pollarded
each winter from century-old trunks that had never been mature trees, often
looking like fields of spiky sea urchins. Weavers here were said to harvest the
willow on St. Bridget’s Day – Feb. 1 – and with large machete-like tools called
bill-hooks, collected ten tonnes to the acre.
In a copse – a forest of regularly coppiced trees – each tree is marked with
the year it was last felled, and only a fraction of them are felled again each
year. Coppiced trees – harvested every several years or so – are interspersed
with trees allowed to grow to maturity and felled for large pieces of timber. The
latter group – called “standards” – are harvested at a rotation time of about
10 times the coppice; for a coppice cut once a decade, for example, the
standards will be cut once a century.
If more forward-looking souls were to turn their fields into copses, they could
have a regular harvest of wood for many generations to come. Enough copses
around the world could supply the world with paper and timber, warmth and
wildlife without the need to ever fell another forest.
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