Agoseris apargioides
Encyclopedia
Agoseris apargioides is a species in the Asteraceae
Asteraceae
The Asteraceae or Compositae , is an exceedingly large and widespread family of vascular plants. The group has more than 22,750 currently accepted species, spread across 1620 genera and 12 subfamilies...

 or sunflower
Sunflower
Sunflower is an annual plant native to the Americas. It possesses a large inflorescence . The sunflower got its name from its huge, fiery blooms, whose shape and image is often used to depict the sun. The sunflower has a rough, hairy stem, broad, coarsely toothed, rough leaves and circular heads...

 family, and is commonly called seaside agoseris or seaside false-dandelion. It is native to the west coast of the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 from Washington to California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

, where it grows primarily on coastal dunes. This is a low-growing, perennial herb with milky or orange sap, that may be stemless or with long, rhizome
Rhizome
In botany and dendrology, a rhizome is a characteristically horizontal stem of a plant that is usually found underground, often sending out roots and shoots from its nodes...

-like stems that are buried by drifting sand. The leaves form low rosette
Rosette (botany)
In botany, a rosette is a circular arrangement of leaves, with all the leaves at a single height.Though rosettes usually sit near the soil, their structure is an example of a modified stem.-Function:...

s on the ground. They are slender to broad, up to 15 centimeters long, and usually with 3-5 pairs of lobes along the margins (these sometimes lacking). The peduncle
Peduncle (botany)
In botany, a peduncle is a stem supporting an inflorescence, or after fecundation, an infructescence.The peduncle is a stem, usually green and without leaves, though sometimes colored or supporting small leaves...

 of the inflorescence can be as tall as 45 centimeters but is usually much shorter. The flower head
Head (botany)
The capitulum is considered the most derived form of inflorescence. Flower heads found outside Asteraceae show lesser degrees of specialization....

 is up to 2 centimeters wide, surrounded by glabrous to hairy phyllaries
Bract
In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis, or cone scale. Bracts are often different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture...

, and contains yellow ray florets (the outer ones often have a purple strip on the lower surface) but no disc florets. The fruit is an achene
Achene
An achene is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate and indehiscent...

 between 5-12 millimeters long; the lower part of the achene
Achene
An achene is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate and indehiscent...

 contains a single seed, while the upper portion of the achene
Achene
An achene is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate and indehiscent...

 forms a slender beak that possesses a terminal, white pappus
Pappus (flower structure)
The pappus is the modified calyx, the part of an individual disk, ray or ligule floret surrounding the base of the corolla, in flower heads of the plant family Asteraceae. The pappus may be composed of bristles , awns, scales, or may be absent. In some species, the pappus is too small to see...

.

Varieties

  • Agoseris apargioides var. apargioides
  • Agoseris apargioides var. eastwoodiae
  • Agoseris apargioides var. maritima

External links

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