 flower |
 plant |
 rosette |
 leaf sap |
 pappus |
 patch |
Perennial sowthistle
Life cycle: Perennial
Leaves: Deep notched, sometimes almost whole with slightly prickly edges
Stems: Plant starts as a rosette, then bolts soon before flowering
Flowers: Bright yellow color, similar to dandelion. Seeds spread by wind in a similar manner as dandelion.
Roots: Horizontal creeping roots
Comments: Statewide noxious weed. Can be difficult to control once established due to extensive system of creeping roots. Seeds may spread from ditches and germinate in lawns, gardens, or landscapes.
Control
Cultural: Continuous hoeing or clipping, preferably just as the plant is producing flower buds.
Foliar Herbicides: Fall applications preferred for this perennial weed. In lawns, products that contain 2,4-D and dicamba (Weed-B-Gone Max, Trimec, WeedStop, and others), triclopyr (Turflon), or clopyralid (Confront). In gardens, a non-selective herbicide such as glyphosate (Roundup) applied in the fall.
Perennial sowthistle
Life cycle: Noxious statewide. Creeping perennial.
Leaves: Alternate. Dandelion-shaped, 4 to 8 inches. Irregularly lobed, spine-tipped edges.
Stems: Smooth, 3 to 7 feet tall. Entire plant contains milky juice.
Flowers: Branched clusters, yellow-orange, about 1 ½ inches long.
Roots: Deep, spreading.
Weed Species: state noxious weed
Comments: Capable of rapid spread. Most persistent in wet areas.