You could use the gabion framework like a large vase to support dried willow, bamboo or reeds to form a light and lacy screen, or even just dried leaves and twigs like this screen at the De Young Museum.
First up, the gabion: natural stone piled up and held together with wire. It's unexpected and packs both an industrial and natural look. Here's a materials secret: Builders often fill the center with something inexpensive, sturdy and heavy, taking up up a ton of space for less cost. Then higher-quality stone can be poured into the parts we can actually see.