espalier

Tree or other plant trained to grow flat against a support (such as a trellis or wall). The term is also used for the support itself, as well as for the method or technique. The technique was developed in Europe to encourage fruit-tree production in an incompatible climate; it originally used a wall to provide heat as well as support. Decorative or space-saving espaliers use metal, wire, or wooden frames to create ornamental shapes for shrubbery or to train trees on trellises, walls, or fences. Evergreens such as loquat, fire thorn, sweet bay magnolia, and upright yew, as well as dwarf apple and pear trees, make excellent espaliers.

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