An arbor is a freestanding structure, whereas a trellis is an attached support for vines or other plants. Arbors typically have an open roof structure, while trellises are covered (usually with lattice). Arbor structures can be made from a variety of materials, including wood, metal, and vinyl. Trellises are often made from wood or metal.

An arbor is a freestanding structure that is more open, while a trellis is an upright fence-like structure that has a lattice or grid of metal or wood. Arbors are usually used to provide shade and to grow vines, while trellises are often used to support climbing plants.