Patrick Dougherty is a sculptor who uses living trees as an unusual medium. He has created over 200 site-specific sculptures by weaving the saplings of trees into huts, water pitchers, cocoons, etc. Among his installations, the most famous ones are the nest houses that he produced worldwide. For constructing these nest houses, Dougherty uses different tree types including birch, aspen, maple, and pussy pillow, and creates huts reaching 20 to 40 feet in height. Unfortunately, due to the nature of trees, his works cannot last for a long time.