February is the one month of the year that many of us associate with love and romance. We cut out paper hearts for Valentine’s Day cards and wrap-up cut flowers for that special person in our lives. But there is another reason to celebrate. February 14th is also Oregon’s birthday! Way back in 1859, Oregon […]
February is the one month of the year that many of us associate with our love and romance. We cut out paper hearts for Valentine’s Day cards and wrap up cut flowers for that special person in our lives. But there is another reason to celebrate because February 14th also Oregon’s birthday! Way back in […]
Its June, and that means its time for a new Weed of the Month! We are working with our partners at the Columbia Gorge Cooperative Weed Management Area to promote Scotch Broom (Cytisus scoparius) as our weed-of-the-month for June. Scotch broom was introduced as an ornamental along highway corridors and in western Oregon as a […]
Scotch broom, Scot’s broom, English broom
Cytisus scoparius (syns. Sarothamnus scoparius, Spartium scoparium)
Scotch broom is a fast growing shrub in the Fabaceae (pea) family, characterized by its masses of yellow flowers. It grows upright on young green, 5-angled stems which are hairy. Broom forms dense stands and are shade intolerant. Mature plants can reach 10 feet in height although most plants are typically 3-5 feet tall. Scotch broom is deciduous nitrogen fixing plant. Scotch broom is an invasive plant found in low elevations from British Columbia to California.
4 to 8 feet
Yellow
April to June
It can be confused with the less common Spanish broom, Spanish broom has fewer round stems, very few leaves, and larger yellow flowers.
The areas most infested by Scotch broom are disturbed (logged or burned) sites, grasslands, open forests, and riparian corridors. The plant likes coastal areas and low elevations in dry conditions with plenty of sunshine. Scotch broom flourishes in infertile soil because it is a nitrogen fixing plant which allows it to grow where many plants cannot. Scotch broom likes sandy, acidic and dry soil.
Scotch broom is a pioneer species known to displace native plants and smother tree transplants increasing tree death or slowing growth in the early years. It readily invades disturbed sites, natural areas, dunes, and forestlands. Broom control costs on right-of-ways, public facilities, parkland and private property are in the millions of dollars each year due to its rapid growth and persistent nature. Scotch broom is a prolific seed producer of long-lived (10 years plus) seeds. Broom stands establish persistent soil-seed banks requiring long-term commitment to exhaust. The costs attributed to Scotch broom come from labor and chemical inputs needed to control infestations ($47 million annually) in timberlands and from lost productivity. Pollen production during bloom time also can be quite an allergen source for allergy sufferers.
Europe and North Africa
Oregon Noxious Weed Profile
Washington Noxious Weed Profile
Invasive.org profile
CABI Invasive Species Compendium
