It’s also a chance to see trees at war with each other. Trees — and all plants — compete mercilessly for light, even in some gardens where there are more plants than available sky. (Or if there’s enough sunlight, they fight over something else, like water.) In 1820, botanist and taxonomy pioneer Augustine Pyrame de Candolle said, “All plants of a given place are in a state of war with respect to each other.”
If you visit a tropical rain forest, the darkness at ground level may surprise you. Now look up. You can see a green ceiling, the forest canopy. That’s why it’s so dark. The leaves up there absorb all the sunlight.
Look down. On the forest floor, you can see a few ferns, struggling saplings, gaunt seedlings, some moss, and a lot of roots, but not much else. Few leaves grow beneath the canopy. It’s too dark. Everything aims for the canopy to grab the sunlight.
Trees use brute force, investing in thick trunks to carry their branches upward. Saplings stand here and there in the jungle, but young trees flourish only after an old tree crashes down, ripping a hole in the canopy. Light pours onto a waiting sapling that will rise like a titan.
Trees joust with each other. Softwood trees grow faster and outrace the hardwoods to reach the top first for their day in the sun. Hardwoods follow, slowly sawing their way up: hardwood branches, stirred by winds, grind against softwood branches and carve through, amputating softwood branches one by one.
When I see this video, I see trees wafting like gentle waves — and I see carnage, horrible sap-bleeding injury, and heartless brutal warfare. For me, a walk in the woods is both glorious and horrific, a place of exquisite cooperation and life-or-death competition. A tree faces its challenges fully armed and dangerous, an invaluable ally and a potent foe. Beware.