The common dandelion, Taraxacum officinale Weber, sometimes known as Lions-tooth, Blow-ball or Cankerwort, is native to Eurasia, but has been naturalized throughout most of the temperate United States.

Life Cycle:

The dandelion is a perennial with a thick fleshy taproot. It spreads by seeds and by new shoots from roots or root segments. It flowers from early spring to late fall. Seedlings may occur throughout the spring and summer and are often abundant in the fall.

Habitat:

Common dandelion is the most common broadleaf weed in many lawns. It is found in virtually every kind of habitat, from openings in deep woods to cultivated fields, from rocky hillsides to fertile gardens and lawns.

Description:

The dandelion has a thick fleshy taproot with many-branched crowns and milky juice. Stem is very short and wholly underground, producing leaves at the ground surface. Leaves are simple, 3 to 10 inches long, and contain a milky juice. Leaves vary in shape, from lobeless or entire to deeply cut lobes. Flowerheads are golden-yellow and 1-2 inches in diameter, with yellow ray flowers, borned on a long, hollow stalk. Achenes are yellowish-brown with 5 to 8 ribs on each side and minute curved spines on the rib margins of the upper half of the seed. Seeds are tannish, about 3/16 inch long, elongated, with a slender tip bearing a tuft of hairs that are easily broken off.

Control:

Cultural: Maintaining a dense, healthy, vigorous lawn is the best method of controlling many turf weeds. The use of an adapted species of grass, adequate fertilization, proper mowing and irrigation practices and insect and disease control is the best way to minimize weed problems. Low nitrogen fertilization will encourage weeds due to less competition from desirable species. Mowing as soon as the first flowerheads appear can reduce further infestations.

Chemical: Dandelions can be controlled by herbicides as well, if necessary. Herbicides may be applied to dandelions in spring or fall, providing that the dandelion is actively growing. Early fall may be the best time to treat dandelions. The lawn should not be mowed for two or three days before and after herbicide application. The treatment application should be done at a time when there is not rainfall for at least 24 hours.

Adapted from Prasanta C. Bhowmik, University of Massachusetts Cooperative Extension, 2001