Family: Fabaceae, Pea view all from this family
Description Cytisus scoparius, the Common Broom and Scotch Broom, syn. Sarothamnus scoparius, is a perennial leguminous shrub native to western and central Europe.
In Britain and Ireland the standard name is Broom, but this name is also used generically for other related species, and the term Common Broom is sometimes used for clarification. In other English-speaking countries, the most prevalent common name is Scotch Broom (or Scot's Broom); English Broom is also occasionally used.
There are two subspecies of Cytisus scoparius:
Cytisus scoparius subsp. scoparius. Throughout the species' range.
Cytisus scoparius subsp. maritimus (Rouy) Heywood. Western Europe, on maritime cliffs. Differs in prostrate growth, not over 0.4 m tall, and downy young shoots.
Plants of Cytisus scoparius typically grow to 1–3 m (3–9 ft) tall, rarely to 4 m (13 ft), with main stems up to 5 cm (2 in)thick, rarely 10 cm (4 in). The shrubs have green shoots with small deciduous trifoliate leaves 5–15 mm long, and in spring and summer is covered in profuse golden yellow flowers 20–30 mm from top to bottom and 15–20 mm wide. Flowering occurs after 50-80 growing degree days. In late summer, its legumes (seed pods) mature black, 2–3 cm long, 8 mm broad and 2–3 mm thick; they burst open, often with an audible crack, forcibly throwing seed from the parent plant. This is the hardiest species of broom, tolerating temperatures down to about -25° C, +10° F. Cytisus scoparius contains toxic alkaloids that depress the heart and nervous system.
Cytisus scoparius is found in sunny sites, usually on dry, sandy soils at low altitudes. In some places outside of its native range, such as India, South America and western North America, it has become an ecologically destructive colonizing invasive species in grassland, shrub and woodland, and other habitats .
As a legume, the shrub fixes nitrogen in the soil by a symbiotic relationship with Rhizobium bacteria.
Habitat Cities, suburbs & towns, Scrub, shrub & brushlands, Fields.
Range Alaska, Rocky Mountains, Southwest, Great Lakes, Texas, Eastern Canada, California, Southeast, Mid-Atlantic, New England, Western Canada, Northwest.