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Scotch Broom

(Cytisus scoparius)

Scotch Broom

(1B, limited presence in Montana)

(Cytisus scoparius)

Quick ID
  • Seeds pods that are hairy along the edges and turn black when mature
  • Bright yellow pea-type (papilionaceous) flowers consisting of a banner petal, two wing petals, and two fused keel petals
  • Large true shrub, can be 10’ or taller when mature, and can grow up to 8’ tall in 2 years, with woody stems as plant ages
Scotch Broom Map

Map Courtesy of Montana Natural Heritage Program, Scotch Broom – Low Suitability: 7% of Montana, Moderate: 1%, Optimal: 1%. Click here for larger image.

Scotch Broom
Scotch Broom Plant

Video Information

Weed Images

Scotch Broom plant
Scotch Broom flower
Scotch Broom Leaves - Photo by Leslie J. Mehrhoff, University of Connecticut,
Scotch Broom Seed - Photo by Eric Coombs, Oregon Department of Agriculture,
Scotch Broom Stem
Scotch Broom Mature -  Photo by Gil Wojciech, Polish Forest Research Institute,
Scotch Broom Invading -  Photo by

Weed Specifications

Weed Info
Type Information
Toxicity Toxic, but rarely grazed
Best Management Practices

Hand-pull small, young plants; cut the stem with loppers as close to the ground surface as possible with older plants, the lower the cut, the less chance for regrowth, then collect and dispose; herbicide, repeated mowing, repeated prescribed burns, continued prevention

*See additional documents below
Habitat Disturbed areas, roadways, open forests, prefers full sun, associated with road construction and timber harvesting
Root Deep taproot
Leaves Small (~1/4”), simple on the upper branch, trifoliate on the lower branch, alternate
Lifespan Long-lived (20 years or more) deciduous perennial shrub
Similar Looking Plants In Montana, golden banner (Thermopsis montana) and Siberian peashrub (Caragana arborscens), as well as Portuguese broom, Spanish broom, and French broom, which are not in Montana but are in nearby states
Important Information Only reproduces by seed, but each plant can produce tens of thousands of seeds, and seeds can remain viable in the soil for decades; forms dense stands, introduced as an ornamental and as erosion control

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To Report, Contact:


Kellieann Morris
Ravalli County Noxious Weed Coordinator
Montana Scotch Brook Task Force Coordinator
Phone: 406-777-5842