Smooth Mule Ears

Smooth Mule Ears © DSchiel

Coast Range Mule Ears, Shining Mule Ears
Wyethia glabra

Description (Jepson,

  • Eudicotyledon
    • Eudicots are a major lineage of flowering plants; see family for general characteristics
  • Sunflower Family (Asteraceae)
  • Perennial herb
    • Grows from a taproot and caudex (persistent, often woody base of a perennial herb)
  • Leaves
    • Mostly basal, alternate
    • Large (to 18 in.), wide, lance-shaped to oval
    • Usually shiny, smooth, and hairless
    • Cauline leaves (along the stem) similar but smaller
  • Flowers
    • Inflorescence (flower arrangement) usually a single golden-yellow flowerhead
    • Radiate head (see Sunflower family), up to 2 in. in diameter
      • 20-27 outer 3-lobed ray flowers, up to 2in. long, suggesting petals
      • 35-150+ central disk flowers
    • Phyllaries (vase-like floral bracts, collectively called the involucre) in 2-3 series, with the outer large and leaf-like, ≥ the ray flowers
    • Stalk of the entire inflorescence (peduncle) 8-12 in. long and softly hairy
    • Ovary inferior (attached below other flower parts)
  • Fruit is an achene (a single-seeded, dry fruit that does not split open)
  • Height to 16 in.
Inflorescence © TCorelli


  • Native and endemic (limited) to California
    • Grows generally in shady areas
    • See Calflora for statewide observations of this plant
  • Grows at elevations to 3,120 ft.

Uses (San Mateo County Parks prohibits removal of any natural material)

  • Wildlife
    • Frequented by numerous insects including butterflies seeking nectar, e.g. monarch (Danaus plexippus), variable checkerspot (Euphydryas chalcedona), and propertius duskywing (Erynnis propertius)
    • Larval food source (host) for the painted lady butterfly (Vanessa cardui)
  • Native people
    • Young plant shoots eaten (Anderson 2005)
    • Seeds used in pinole or eaten fresh
      • Pinole is a general term for various flours made from the ground, toasted seeds of wildflowers and grasses, eaten dry or moistened and shaped into balls or cakes (Anderson 2005)
      • “Pinole” is a Hispanic version of an Aztec word

Name Derivation

  • Wyethia (wy-ETH-ee-a) – named in 1834 by botanist Thomas Nuttall for Nathaniel Jarvis Wyeth (1802-1856), an American inventor (e.g. ice harvesting tools), plant collector, and explorer
    • Wyeth was an Oregon pioneer, establishing the pathway that became known as the Oregon trail, and is distantly related to the painter Andrew Wyeth
  • glabra (GLAY-bra) – from the Latin, meaning “smooth or hairless” referring to the leaf
  • Mule ears – referring to the shape of the leaves, which are particularly large and wide on some species, e.g. smooth mule ears


  • Flora of North America notes that “Wyethia glabra grows in the Coast Ranges, often in the fog belt”
    • At Edgewood, this species is found at the north side of the preserve, which is most influenced by coastal fog from the HIghway 92 cut

ID Tips

Narrow-leaved Mule EarsSmooth Mule Ears

narrow, often wavy-edged

rough or hairy
wide, smooth-edged

smooth and shiny
Phyllaries¹shorter than ray flowerslonger than ray flowers

full sun

open grasslands
part shade

woodland edges
¹ Phyllaries – vase-like floral bracts, collectively called the involucre

At Edgewood

  • Found usually in part shade, often at the margin of woodlands
  • Flowers March – June

See General References

Specific References

Anderson, M.K. 2005. Tending the Wild. University of California, Berkeley.

Caldwell, J.A. 2014. California Plants as Resources for Lepidoptera: a Guide for Gardeners, Restorationists and Naturalists.

Mitchell, M. 2017. Asteraceae: Sunflower family – Heliantheae (sunflower) tribe: miscellaneous 2. Monterey County Wildflowers, Trees, and Ferns – A Photographic Guide.

Shapiro, A.M. and T.D. Manolis. 2007. Field Guide to Butterflies of the San Francisco Bay and Sacramento Valley Regions. University of California Press, Berkeley and Los Angeles, California.