The Inca civilization–which flourished in the essentially treeless altiplano–made do with what it had, achieving astounding mastery over stone and fiber (grass and wool). Their palaces, as well as the houses of commoners, were built of stone and thatched with grass. Their bridges, like their homes, were constructed of the same materials: stone for the foundations, grass woven into rope for the bridge itself. In a previous post I included this image of an Inca bridge that has been rebuilt for centuries using ancient methods:
As a footnote to that entry, here’s a fascinating video about how that same bridge is actually constructed: The bridge at Q’eswachaka
Those interested in the indigenous peoples of the two Americas (including the Mapuche and the Inca) will find much more to enjoy at: The National Museum of the American Indian.