Dandelion, Taraxacum officinale

Life Cycle

Perennial.

Propagation

Reproducing only by seed.

Stems

Smooth, leafless, succulent and round hollow stem that shows a milky substance when broken.

Leaves

Leaves in a basal rosette. They are elongated, deeply and irregularly lobed along each side or sometimes just shallowly toothed with the amount and shape of lobing or toothing being extremely variable from one plant to another.

Flowers and Fruit

Flower heads bright yellow, 3.2-5cm across, borne singly on long, smooth, leafless, unbranched, hollow stalks which arise from among the rosette leaves. Only ray (strap-shaped) florets are present; outer row of involucral bracts short and spreading or bent down; seed heads white, more or less spherical, 3.5-5cm across. The seeds are long, slender with a slender beak tipped with a tuft of white hair (pappus or "parachute"). The whole plant contains sticky white juice. Flowers from early spring to late autumn.

Roots and Underground Structures

Thick, deeply penetrating taproot.

Habitat

Dandelion occurs throughout Ontario in virtually every kind of habitat, from openings in deep woods to cultivated fields, from rocky hillsides to fertile gardens, and lawns.

Distinguishing Features

It is distinguished from other plants with milky juice and lobed or divided leaves in rosette stage by the soft texture and irregular lobing of leaves, the absence of prickles on margins or midribs, the smooth or softly hairy leaf surfaces, and a deeply penetrating taproot. Flowering plants are distinguished by their large yellow flower heads with only ray (strap-shaped) florets and borne singly on long, unbranched, leafless, hollow stalks which arise from among the rosette leaves, these followed by white, spherical seed heads up to 5cm in diameter.

Many songs have been written about dandelion, the most famous being by The Rolling Stones, http://www.youtube.com/watch?v=Zf0s3L8L7S0 to view a video of this song.


Figure #1.

Dandelion. A. Plant. B-F. Variations in shape and lobing of leaves on different plants. G. 1 "seed"


Figure #2.

Seedling plant.


Figure #3.

Leaf profile


Figure #4.

Rosette.


Figure #5.

Plant with both flowering and mature seedheads.


Figure #6.

Yellow flower head of dandelion.


Figure #7.

Seedhead of dandelion.