The South Fork of the Eel River, which the Avenue follows for its entire length — the reason the big trees grow on these flats.
That water flashing through the trees on your LEFT is the South Fork of the Eel River, and it's no accident this road and these trees follow it. The very biggest redwoods don't grow up on the ridges — they grow down here on the river FLATS, where floods have laid down deep, rich silt for thousands of years and where the groundwater never fails in the dry summer. The flats are the giants' nursery. And here's the strange part: a flood that would kill most trees is exactly what a redwood wants. Bury its trunk in six feet of silt and it simply grows a whole new root system up into the new soil and keeps climbing. That's part of how they get so tall and live so long. Remember the river's power, though — Boone has a tale about the day it turned on the towns along this road, and it isn't a gentle one.