Scotch broom

Cytisus scoparius (L.) Link

U.S. Nativity: Exotic
Habit: Shrub

Synonym(s): Scottish broom, English broom, scotchbroom

Cytisus scoparius is a perennial shrub that grows on average from 3.3-9.8 ft. (1-3 m) tall, but can reach to 13 ft. (4 m). The stems are five-angled and remain green all year.
Leaves are small, alternate and compound with 3 leaflets. The leaves are often not noticeable, due to the dark green stems.
The flowers are bright yellow, resemble sweet pea flowers, and occur singly or in pairs in the upper leaf axils. They bloom from late May to June.
Seed pods are fuzzy on the edges, 1-2 in. (2.5-5 cm) long, and will explode when mature forcefully expelling the seeds. The seeds are small and multi-colored, ranging from green to brown to reddish brown.
Ecological Threat
Cytisus scoparius occurs along roadsides, coastal sites, disturbed sites, pastures, and dry scrubland. Its nitrogen fixing ability allows it to compete successfully on poor, dry, sandy soils. It grows well in full sun. It has been considered a pest weed since the 1920’s on the West Coast. Cytisus scoparius is native to western and central Europe. It was introduced into the United States as an ornamental in the early 1800s.

Identification, Biology, Control and Management Resources

Element Stewardship Abstract - The Nature Conservancy
Invasive Plant Atlas of New England - University of Connecticut