Agoseris retrorsa

Summary

Agoseris retrorsa is a North American species of flowering plant in the family Asteraceae known by the common name spearleaf agoseris or spearleaf mountain dandelion.[2]

Agoseris retrorsa
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Asterids
Order: Asterales
Family: Asteraceae
Genus: Agoseris
Species:
A. retrorsa
Binomial name
Agoseris retrorsa
Synonyms[1]
  • Microrhynchus angustifolius Kellogg
  • Microrhynchus retrorsus Benth.
  • Troximon retrorsum (Benth.) A.Gray

It is native to western North America from Washington to Utah to Baja California, where it grows in many types of habitat, including chaparral, scrub, and coniferous forest.[3][4]

Description edit

Agoseris retrorsa is a perennial herb forming a base of leaves about a number of erect, thick, wool-coated inflorescences up to half a meter in height. The narrow leaves are linear to lance-shaped, and spearlike with curving toothlike lobes along the edges.[2]

The inflorescence bears a single flower head which is several centimeters wide when fully open. It is lined with woolly, pointed phyllaries which are green, often with reddish purple longitudinal streaks or stripes. The flower head contains many golden yellow ray florets, the outer ones usually darker in color.[2]

The fruit is an achene with a plumelike pappus of white bristles.[2]

References edit

  1. ^ The Plant List Agoseris retrorsa (Benth.) Greene
  2. ^ a b c d Flora of North America, Agoseris retrorsa
  3. ^ Biota of North America Program 2014 county distribution map
  4. ^ Calflora taxon report, University of California, Agoseris retrorsa (Benth.) E. Greene Spearleaf mountain dandelion, spear leaved agoseris, spearleaf agoseris

External links edit

  • Jepson Manual Treatment: Agoseris retrorsa
  • United States Department of Agriculture Plants Profile: Agoseris retrorsa
  • Agoseris retrorsa — Calphotos Photo gallery, University of California