Shrubs are perennial, multi-stemmed woody plants that are usually less than 13 to 16 ft. (4 to 5 m.) in height. Shrubs
typically have several stems arising from or near the ground, under certain environmental conditions may be taller
than 5 meters or single-stemmed. Subshrubs are low-growing shrubs usually under 1.5 ft (0.5 m) tall, never exceeding
3 ft. (1 m.) tall at maturity. The following species have been reported to be invasive in natural areas in the U.S.
Species native to the U.S. are included when they are invasive in areas well outside their known natural ranges, as a
result of human activities. For more information on each species, including the listing sources, images, and
distribution maps, click on the species.