Indigenous practices changed which trees grew, for instance the Gary oak was much more prevalent in areas they tended. But old growth was predominantly removed by settlers.
If you want to specifically hike through the old-growth forests, Olympic Peninsula in WA is the best option.
Humans were modifying the Earth on the continent-wide scale long before the industrial age.
I'm a PNW native, you don't need to tell me about the small sliver of old growth we still have in the Olympics.
Yes, and that's a fancy way of saying "used periodic burns" to remove the vegetation to make the land more hospitable for grazers. Meaning more animals to hunt, this was arguably a form of agriculture and also served to reduce the risk of catastrophic wildfires.
> I'm a PNW native, you don't need to tell me about the small sliver of old growth we still have in the Olympics.
Then you should actually learn about the history, and not its Disneyified version.