Like life without rain, it would be hard to imagine urban existence without the sheltering sway of trees to break the angular cityscape.
When I was living in a desert country some years back, my appreciation for these shady friends grew immeasurably.
It was not just their shape that softened the metropolitan monotony; their very greenness seemed a statement of promise.
And like the rain, these trees made only a spartan appearance in Cairo's jammed streets. They were dust-encrusted specimens, struggling for a root-hold in an unforgiving environment - pollution, relentless noise, blasting heat, and soil like sand. Yet they held their own.
When the rain did come, it was too often only enough to turn dust to mud and leave the trees dripping dirt.
But in a land of spectacular ancient monuments, these graceful survivors offered their own testament to fortitude and resilience.
Laurent Belsie's article (at right) about the giants in size and years one finds in the American West adds a further dimension to the tree story.
The oldest tree in California - in the world, in fact - has stood its ground for 12,000 years, sprouting in the soil only a few centuries after prehistoric people arrived on these shores. Its name: Eternal God.
Twelve thousand years. It's a number hard to grasp. It's pre the great pyramids, pre Stonehenge, pre almost all written or recorded history.
Even as people grapple with the excitement of the approaching millennium, this titan has witnessed 12 millennia and counting.
Maybe even a silent tree can offer lessons in timelessness and continuity.
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