arbors <p>Light, open structures either formed from trees, shrubs, or vines closely planted and twined together to be self-supporting or formed from a latticework frame covered with plants; generally less extensive and less substantial than "pergolas."</p> <p> </p> <p>Source: Art and Architecture Thesaurus</p> <p><a href="http://vocab.getty.edu/page/aat/300006781">http://vocab.getty.edu/page/aat/300006781</a> </p>