Many crop plants require support of some type upon which to grow, including passion fruits, pepper, vanilla, and yams. Trees have often been used as a form of live support. In such cases, the vining crop can benefit from the trees service roles, while some tree products might also be harvested.
Spacing depends on the vine crop, but spacings are typically close and geometrical. The tree canopy can be pollarded to control shading. The tree can also be girdled, resulting in a dead trellis up which the vine can grow. The tree will coppice from below the girdled area, and this can be periodically cut and applied as green manure.
Genera that have been used for support trees are generally the same as those used in hedgerow intercropping: Gliricidia, Leucaena, and Sesbania.