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Scotch Broom

(Cytsus scoparius)

Common Names

English broom, broomtops, common broom, European broom, Irish broom, Scot’s Broom


Scotch broom is an evergreen perennial shrub that can reach heights of 13 feet. Its aggressive root system consists of a taproot that may exceed 2 feet in length with large, shallow lateral roots. Leaves are alternate and compound in clusters of three at the stem on lower branches. In the summer, leaves are not readily noticable. Leaflets are approximately an inch long, oval shaped, darker green on the top of the leaf and paler and hairy on the underside of the leaf. Flowers bloom a bright yellow in color from March to June and resemble sweet pea flowers. Flowers occur individually in axils of the leaves and are around one inch in length. Seeds are flat pods that are dark colored with fuzzy edges. They are one to two inches long and, like spurge, will explode when mature. Plants will produce up to 60 seed pods per plant by the second year. Scotch broom reproduces through seed or through sprouts from the root crowne.

Key Features

Bright yellow pea-like flowers, less noticable leaves on the upper branches in the summer season.


Scotch Broom has a high tolerance for most soil conditions but thrives best in full sun on dry, sandy soils.  Scotch broom invades disturbed areas, open forests, roadsides, grasslands, pastures, cultivated fields, wasteland, dry meadows, dry riverbeds and other waterways.

Currently found in the following counties:

Lincoln, Sanders


Interesting Facts

Seeds can remain viable for sixty years. Ants aggressively collect the seed of Scotch broom, assisting in dispersal. This shrub was another introduced ornamental, brought in to the U.S. in the 1800’s.

Commonly Confused Plants

  •  Spanish Broom

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Photo credits:Photo Credits: Utah State University Archive, Utah State University,; Gil Wojciech, Polish Forest Research Institute,; Matthew E. Cohen,; ©J. Brandt,