Good suggestions so far. Hard to think up too many more, really.
“A Shoe” … not shoes … just 1 shoe. It’d be unwearable, but maybe you could cut it up. I see random single shoes far too often on roadsides.
Trucker Caps/Baseball caps that are rather beat up. I see hats often too.
Sunglasses. Usually beat up or broken.
Unreadable magazines (too wet and/or muddy to read … but they’d burn.)
Discarded prophylactics. Hey look Griz, a new source of plastic, if you dare! LOL
If you add traffic cones, I want a “Traffic Cone Hat” recipe.