Weeds-Scotch Broom

SCOTCH BROOM Back

Scotch broom is a perennial shrub. It reaches heights up to 10 feet and has stiff, angled, more or less erect, dark green, broom-like branches. The bright yellow flowers are about ¾ inch long, shaped like pea flowers, and bloom from April to June. The brown or black pods are flat with hairs on the margins only. Each contains several oval shaped, shiny surfaced seeds. Seeds can last for 60 years in the soil. This plant grows in thickets and is very aggressive. It occupies pastureland at the expense of desirable forbs and grasses, and often forms pure stands along public roads. It has plenty of help from people to move it to new sites. The seed is a regular hitchhiker on vehicle tires, heavy equipment, and in infested gravel.

Control

Mechanical: Manual or hand pulling can be effective if care is taken to extract all of the stump and roots, minimize soil disturbance, and not spread mature seed. This technique is very labor intensive and costly. Scotch broom will not persist in cultivated fields because of tillage. The land should be plowed as deeply as possible and cultivated several times during the balance of the season. Periodic mowing will reduce seed production. Fire is often an inadequate control method.
Biological: Livestock will rarely consume Scotch broom, however domestic goats are reported to browse without apparent ill effects. Although not deliberately introduced into the Pacific Northwest, a stem feeding moth, Leucoptera spartifoliella, is fairly widespread in certain areas. The seed weevil, Apion fuscirostre, has established in many sites throughout Western Oregon. The shoot tip leaf moth, Agonopterix nervosa, was accidental introduced in the 1920's. It has been found in many different sites.
Chemical: Control with herbicides or any combination of methods requires follow-up measures. Herbicide containing triclopyr has proven effective for control in rangelands, pastures and other non-crop areas.

When choosing any kind of control method, assure that your choice is suited for your particular situation. Always read and follow the product label before applying any herbicide.