There is a lesson learned
from the tenacious and tiresome winter which, according to the calendar, ended
last week.
It comes on an almost-spring
breeze that brushes my cheeks as I walk a snow-covered path through a copse of
young oaks and beeches that appear to be stone cold dead.
The breeze carries an
unhurried clicking sound that is out of place and unnatural in these somnolent
woods. I stop to listen and look about to find the source.
Over my shoulder I see a
single leaf tossing restlessly in the breeze. It is an oak leaf – brown and
brittle - that has clutched its branch desperately through many weeks of
blowing snow, freezing rain and bitter temperatures. A single sign of life in
an otherwise lifeless forest.
The leaf fluttering on its
branch may appear to be a sign of life but it is in fact dead, and has been
since last fall. How and why it has clung through the brutal winter is a matter
of scientific speculation.
Dead or not, the leaf for me
is a lesson in courage. It succumbed in a natural process many months ago but refused
to fall, becoming a symbol of resistance to the cruelty of winter.
A few other trees around me
also hold dark brown oak and pale tan beech leaves. Some will succumb to early
spring winds but others will remain until the new growth of May demands their
space.
The botanical term for
leaves that do not fall on schedule is marcescence. It’s a word that comes from
Latin (whither) but it does not explain why some leaves hang on through the
brutish winter months.
The trees I see with dead
leaves still attached to their branches are all oaks and beeches (which,
incidentally, are related even though their leaves are distinctly different).
They are two of just a few deciduous species that refuse to drop all their
leaves in autumn. Another common one is hornbeam, which some of us call
ironwood.
There are a number of
theories why these trees retain some leaves throughout the winter. One is that they
hold leaves until spring then drop them to deliver new organic feed that the
tree really needs after a long winter hibernation.
Oaks and beeches often grow
in poor soil conditions – dry, rocky areas – and even small amounts of
nutrients provided by dead leaves in spring are considered helpful to their
growth.
Another theory is that dead
leaves block blowing snow, forcing it to fall to the base of the tree, thus
providing small amounts of much needed water in spring.
Yet another theory is that clinging
dead leaves provide some frost protection for buds and new twigs that begin to
grow as the weather warms during spring days. And still another study holds
that dead leaves help to hide succulent new buds from browsing moose and deer,
saving them to grow into new shoots and leaves.
Those theories sound a bit
stretched but no one simply made them up. They are based on scientific
observations and research studies.
Despite the studies and the
bright minds that conduct them, there is no definitive answer why some trees
retain leaves they should shed in autumn. We simply do not know why.
And that’s a good thing.
It’s good that nature keeps some secrets because without some mysteries life
would be very boring.
The German theoretical physicist Max Planck,
who won a Nobel Prize in 1918,
had some thoughts on nature’s secrets:
Mysteries
aside, the fact is that even the most stubborn leaves fall eventually, joining millions
of others in the miracle of decomposition that provides nutrient rich food for
trees and other plants. It’s the perfect example of spent lives providing for
new life.
The
dead leaves that cling through winter only to drop in spring also provide a bit
more raking, which we thought had ended in November. However, raking is a lot better
than shovelling snow.
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