A leaf's lesson in courage
By Jim Poling
Published March 28, 2019
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:
“Science cannot solve the ultimate mystery of nature,” he wrote in his 1933 book Where Is Science Going? “And that is because, in the last analysis, we ourselves are a part of the mystery that we are trying to solve.”
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.