Shrubs are trees with multiple stems. In comparison to true trees, shrubs are considerably lower in height. Bushes are shrubs but not all shrubs are bushes, which require a degree of "denseness". Like trees in general, they are woody plants. Some plants can be considered both "shrub" and "tree" depending on their height and growing condition. Shrubs are usually broad-leaf plants, although some pines are also considered shrubs if they are bushy in nature.