WSU Extension

Hortsense

Weeds
 
Annual bluegrass 
Barnyardgrass 
Bentgrass, creeping 
Bermudagrass 
Bittercress (Shotweed, Hairy bittercress) 
Bittersweet nightshade (European bittersweet) 
Black medic 
Blackberry (Himalayan, Evergreen, Pacific) 
Blue mustard (Purple mustard, Tenella mustard) 
Brackenfern, western 
Buffalobur 
Bull thistle 
Buttercup, creeping 
Canada thistle 
Catchweed bedstraw (Cleavers) 
Catsear, common (False dandelion) 
Chickweed, common and mouseear 
Clover 
Comfrey 
Crabgrass 
Dandelion 
Dock (Curly, Broadleaf) 
Dodder 
Downy brome (Cheatgrass, Downy chess) 
Dwarf mistletoes 
English daisy (Lawn daisy) 
English ivy 
Field bindweed (Wild morningglory) 
Field pennycress (Fanweed) 
Flixweed 
Foxtail (Green, Yellow, Bristly) 
Garden loosestrife 
Giant hogweed 
Goldenrods 
Groundsel, common 
Hawkweeds 
Hedge bindweed 
Henbit 
Herb Robert (Robert geranium, stinky Bob) 
Horsetails (Scouringrush) 
Horseweed (Marestail) 
Knapweeds 
Knotweeds (Bohemian, Giant, Japanese, Himalayan) 
Kochia 
Lambsquarters, common 
Liverworts 
Mallow, common (Cheeseweed, Buttonweed) 
Nightshades 
Oxalis (Creeping woodsorrel) 
Parrotfeather and Eurasian watermilfoil 
Pineappleweed 
Plantain (Broadleaf, Buckhorn) 
Poison hemlock 
Poison ivy and Poison oak 
Prickly lettuce (China lettuce) 
Prostrate knotweed 
Puncturevine (Tackweed, Goathead) 
Purple deadnettle (Red deadnettle) 
Purple loosestrife (Purple lythrum) 
Purslane, common 
Quackgrass 
Red sorrel (Sheep sorrel) 
Redroot pigweed (Rough pigweed) 
Redstem filaree (Stork's bill, Crane's bill) 
Reed canarygrass 
Russian thistle (Tumbleweed) 
Ryegrass, annual (Italian ryegrass) 
Salsify (Goatsbeard) 
Scotch broom 
Shepherd's-purse 
Smartweeds 
Sowthistle, annual and perennial 
Speedwells 
Spurges (Prostrate spurges) 
St. Johnswort, common (Goatweed, Klamathweed) 
Stinging nettle 
Tansy ragwort 
Tumblemustard (Jim Hill mustard) 
Velvetgrass (Common velvetgrass) 
Velvetleaf 
Water primrose 
Waterhemlock, western 
Yellow nutsedge 



print version| pdf version| email url    
Caption: Scotch broom flowers
Photo by: T. W. Miller
  
Weeds : Scotch broom : Cytisus scoparius
(revision date: 9/3/2015)

Family: Fabaceae (Leguminosae)
Cycle: Perennial
Plant Type: Broadleaf

Biology
Scotch broom is an aggressive, woody shrub reaching up to ten feet in height. The slim, angular, green branches are typically upright. Many branches are leafless. When present, the one- to three-parted leaves are rather inconspicuous. The plant produces very showy, yellow, pea-like blossoms singly or in pairs in the axils of the upper leaves. Bloom typically begins in early spring and may recur sporadically till fall. Seeds are produced in flat green pods which turn dark at maturity. The pods have obvious white hairs on the margins, but are otherwise hairless. Scotch broom spreads by seed, which can remain viable in the soil for many years. SPECIAL INFORMATION: Scotch broom is aggressive and can quickly become a serious problem if left unchecked. It is reported to be toxic to livestock. In WASHINGTON and OREGON, Scotch broom is designated as a Class 'B' noxious weed. In addition, it is on the Washington and Oregon noxious weed quarantine lists, which prohibit sale, purchase, and transport of plants, seeds, and plant parts. Management of this species may be required by law in your county. Consult your local Noxious Weed Control Board for more information.
Habitat
Scotch broom can become a problem in forest, woodlands, pastures, along roadsides, and in other open, uncultivated areas. It was introduced as an ornamental plant.

Management Options

Non-Chemical Management
  • Reduce weed infestation by handpulling weeds.
  • Careful digging is useful to manage weed populations. However, digging can carry undesirable weed seed to the surface and foster further germination.
  • However, this is very time consuming and frustrating.
Select non-chemical management options as your first choice!

Chemical Management

Apply to actively growing plants after bloom drop in spring. When using glyphosate, it is best to sever the plant at the base of the trunk, then paint the injured areas of cambium with herbicide. NOTE: Some ingredients listed here are only available in combination. Read the label carefully on combination products to make sure the product is suitable for your specific situation.

Landscape areas
  • glyphosate
Turf areas
  • triclopyr
Bare ground areas
  • glyphosate
  • products containing 2,4-D
  • triclopyr
Images

+ Show larger images

 
Caption: Scotch broom flowers
Photo by: T. W. Miller
Caption: Scotch broom along highway
Photo by: T. W. Miller
Caption: Scotch broom flowers closeup
Photo by: T. W. Miller
Caption: Scotch broom fruits
Photo by: T. W. Miller
Caption: Scotch broom stand
Photo by: B.M. Johnson
Caption: Scotch broom young plant
Photo by: B.M. Johnson
Caption: Scotch broom old seed pods
Photo by: B.M. Johnson