shrub

Any woody plant that has several stems, none of which is dominant, and is usually less than 10 ft (3 m) tall. When much-branched and dense, it may be called a bush. Intermediate between shrubs and trees are arborescences, or treelike shrubs (10–20 ft, or 3–6 m, tall). Trees are generally defined as woody plants more than 20 ft (6 m) tall, having a dominant stem, or trunk, and a definite crown shape. These distinctions are not reliable, however; for example, under especially favourable environmental conditions, some shrubs may grow to the size of an arborescence or even a small tree.