A shrub or bush is a small to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees by their multiple stems and shorter height, less than 6–10 m tall. Small shrubs, less than 2 metres tall are sometimes termed as subshrubs. Many botanical groups have species that are shrubs, and others that are trees and herbaceous plants instead.
Some define a shrub as less than 6 m and a tree as over 6 m. Others use 10 m as the cutoff point for classification. From Wikipedia
