The point is to avoid that entirely and harvest gravity.
Re-wilding teams already climb far and wide, and this would extend their reach without increasing their dependencies.
Ammo is a dependency.
And if you INSIST on making everything completely low-tech and renewable, build a potato gun and use high-proof alcohol as fuel. It'll weigh less and last longer than whatever rube-Goldberg trebuchet design you have.
It's not obvious whether a trebuchet is better than compressed air, like a BB gun.
All harvesting requires some secondary-energy source.
Gravity is a resource, it takes effort to convert it to a form that can be applied - just like wheat, photons, air guns, etc.
> It's not obvious whether a trebuchet is better than compressed air, like a BB gun.
True, it’s not obvious yet, but it sure is fun following along and imagining the final, highly optimal version making its way through the process. I’d use it for some seed bombing hijinks, anyway. Green up the place, I would.