Greenbrier is the name for several types of climbing vines that have prickly green stems. Greenbriers are also known as horse briers and catbriers. These plants have shiny leaves and clusters of small, yellowish-green flowers. They also produce bluish-black or reddish berries. Greenbriers grow in thickets throughout the eastern half of the United States. Greenbriers can spread rapidly, and the plants often are considered weeds.
