Winter’s over, the days are getting longer, buds are beginning to burst
and the birds that come north in the spring are arriving. Here in the eastern
deciduous forest the leaves on the hardwoods lost their chlorophyll last fall
and began to fall to the ground. For months the hardwood trees have spread bare
branches to the winter sky –
But not all deciduous trees have been
without leaves throughout the winter. Some species have a tendency to retain some or most
of their leaves. Those leaves are dry and brown, but they’re still on the
branches. Younger trees exhibit this tendency more than their older brethren.
Last fall as the days shortened a corky
layer developed where the leaves' petioles (stems) joined the twigs. This is called
the abscission layer and cuts off the water supply to the leaf, resulting in
the death of the green chlorophyll in the leaf. Thus all the leaves died and turned
color brightening the forest with their shades of red, yellow and orange. The
abscission layer weakens the bond between the leaves and the twigs and the leaves fall to
the ground.
Except not all the leaves fell, some hung on
through the rain and snow and wind – and still hang on.
Beech |
Eastern Hophornbeam |
By mid-May the buds on most of our trees
will be open, and the new leaves will be expanding pushing the few remaining old
leaves from the twigs.
Interesting. I also have been noticing that the beech and white oak leaves cling on during winter in our bush lot.
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