It’s hard to find a more perfect material for creating outdoor structures than branches. They’re inexpensive, if not free. They complement the landscape, especially if you’re going for a woodsy vibe. They’re 100 percent organic, and will eventually return seamlessly to the earth from whence they came.
The only trick is finding a source and knowing some patience might be involved. Small Spot Gardens tends to use Bayview Greenwaste; if an arborist is working in the neighborhood, it’s like a tree treasure trove.