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Hortsense

Hortsense Home| Hortsense fact sheets | Weeds | Sowthistle, annual and perennial

Weeds

Annual bluegrass

Bentgrass, creeping

Birdfoot Trefoil

Bittercress (Shotweed, Hairy bittercress)

Bittersweet nightshade (European bittersweet)

Blackberry (Himalayan, Evergreen, Pacific)

Blue mustard (Purple mustard, Tenella mustard)

Brackenfern, western

Buttercup, creeping

Catchweed bedstraw (Cleavers)

Catsear, common (False dandelion)

Chickweed, common and mouseear

Dock (Curly, Broadleaf)

Downy brome (Cheatgrass, Downy chess)

Dwarf mistletoes

English daisy (Lawn daisy)

Field bindweed (Wild morningglory)

Field pennycress (Fanweed)

Foxtail (Green, Yellow, Bristly)

Garden loosestrife

Groundsel, common

Herb Robert (Robert geranium, stinky Bob)

Horsetails (Scouringrush)

Horseweed (Marestail)

Knotweeds (Bohemian, Giant, Japanese, Himalayan)

Lambsquarters, common

Lesser celandine

Mallow, common (Cheeseweed, Buttonweed)

Oxalis (Creeping woodsorrel)

Parrotfeather and Eurasian watermilfoil

Plantain (Broadleaf, Buckhorn)

Poison ivy and Poison oak

Prickly lettuce (China lettuce)

Prostrate knotweed

Puncturevine (Tackweed, Goathead)

Purple deadnettle (Red deadnettle)

Purple loosestrife (Purple lythrum)

Purslane, common

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)

Shepherd's-purse

Sowthistle, annual and perennial

Spurges (Prostrate spurges)

St. Johnswort, common (Goatweed, Klamathweed)

Stinging nettle

Tumblemustard (Jim Hill mustard)

Velvetgrass (Common velvetgrass)

Waterhemlock, western

Wild carrot (Queen Anne's lace)

Yellow nutsedge

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Caption: Spiny sowthistle

Photo by: T. W. Miller

Weeds : Sowthistle, annual and perennial : Sonchus oleraceus, Sonchus arvensis

(revision date: 4/7/2021)

Family: Asteraceae (Compositae)
Cycle: Annual
Plant Type: Broadleaf

Use Integrated Pest Management (IPM) for successful weed management.

Biology

Annual sowthistle grows upright and can reach from one to four feet tall. The lower leaves have a stalk while the upper leaves do not. Most of the leaves are deeply lobed and have one to three lobes on each side. Annual sowthistle produces many pale yellow flower heads that are 1/4 to 3/4 inch wide. The seeds are flat with lengthwise ribs and a parachute-like tuft of fine hairs that aid in wind dissemination. Perennial sowthistle leaves, stems, and flowerheads are often a little larger than annual sowthistle. Perennial sowthistle produces many creeping roots that aid the spread of this creeping perennial species.

Habitat

Sowthistle grows along roadsides, cultivated fields, in gardens and in waste areas throughout Washington.

Management Options

Non-Chemical Management

None recommended

Select non-chemical management options as your first choice!

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides

Glyphosate products should be applied as spot treatments only! 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

2,4-D + MCPP + dicamba

Bare ground areas

glyphosate

Images

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Caption: Spiny sowthistle Photo by: T. W. Miller
Caption: Perennial sowthistle glandular hairs Photo by: T. W. Miller
Caption: Annual sowthistle flower heads Photo by: T. W. Miller
Caption: Annual sowthistle leaf at base of stem Photo by: J.A. Kropf
Caption: Line drawing of annual sowthistle Photo by: Ciba Geigy
Caption: Annual sowthistle flower Photo by: T. W. Miller
Caption: Annual sowthistle Photo by: C.R. Foss
Caption: Annual sowthistle mature head Photo by: T. W. Miller