How to Read a Second-Growth Forest — a stop on the Avenue of the Giants.
Here's a skill that will change what you see for the rest of this drive: learning to tell old growth from second growth at forty miles an hour.
OLD GROWTH — and you'll know it instantly once you've got it — is not uniform. The trees are wildly different sizes and ages. The trunks are enormous and often bare of branches for a hundred feet or more. The canopy is ragged and layered, so the light comes down in shafts. The floor is open, and there are huge fallen logs lying around rotting, because nobody took them away.
SECOND GROWTH looks like a crop, because it is one. The trees are all roughly the same size and age, spaced evenly, thin and straight, branches all the way down. The canopy is a flat even ceiling and the light is dim and uniform. And if you look low, you'll spot the giveaway: gigantic old STUMPS, six or eight feet across, often with springboard notches cut into them — the slots where loggers wedged planks to stand on above the flared base. Sometimes a ring of young trees grows straight out of the old stump.
Once you can see that difference you'll notice the road switching back and forth between the two all day. The protected groves are islands. What's between them is a forest coming back — which, honestly, is its own kind of hopeful thing to look at.