Hill Morning-glory

Hill Morning-glory © EKennedy and FMorse

Stemless Morning-glory, Cambria Morning-glory
Calystegia subacaulis ssp. subacaulis
NATIVE – CA ENDEMIC

Description (Jepson, PlantID.net)

  • Eudicotyledon
    • Eudicots are a major lineage of flowering plants; see family for general characteristics
  • Morning-glory Family (Convolvulaceae)
  • Low-growing perennial herb
    • Grows from a rhizome
  • Leaves
    • Arranged in a basal rosette
    • Triangular-shaped and slightly-lobed
      • Rounded or pointed tips
      • Surface flat or slightly wavy
  • Flowers
    • Inflorescence (flower arrangement) of large, solitary flowers on short stems
    • 5 fused petals, twisted and pleated in bud, opening into a funnel shape
    • White or cream, often tinted with light pink
    • Ovary superior (above the attachment of other flower parts)
  • Fruit is a capsule (a dry, multi-chambered fruit that splits open at maturity)
  • Height to a few inches

Distribution

  • Native and endemic (limited to) California
    • Grows in grasslands, dry open scrub, or woodlands
    • See Calflora for statewide observations of this plant
  • Grows at elevations to 1,600 ft.

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

  • Wildlife
    • Visited by insects

Name Derivation

  • Calystegia (kal-i-STEE-jee-a) – from the Greek kalux, “cup,” and stegos, “a covering,” meaning a covering or concealing cup, probably referring to the leaf-like structures (bractlets) partially concealing the sepals of some species
  • subacaulis (sub-ak-AWL-is) – from the Latin sub, “below,” and caulis, “stalk or stem,” referring to the lack of an obvious stem
  • Morning-glory – flower opens in the early morning

Notes

  • Although members of the Morning-glory family are often vines, hill morning-glory grows in a tidy basal rosette
  • Geophytes (e.g. plants growing from bulbs, corms, rhizomes, or enlarged taproots) are well adapted to survive fire, our Mediterranean climate’s long, dry summers, and extended droughts
    • Above-ground growth dies back after flowering, while underground the plant survives with stored water and nutrients
  • Edgewood’s hill morning-glory is classified as a subspecies
    • Subspecies rank is used to recognize geographic distinctiveness, whereas variety rank is appropriate for variants seen throughout the geographic range of the species; in practice, these two ranks are not distinct

ID Tips

  • May be confused with 2 other morning-glory species at Edgewood – hillside morning-glory (C. collina ssp. collina) and Western morning-glory (C. purpurata ssp. purpurata)
Hill Morning GloryHillside Morning-gloryWestern Morning-glory
Growth Habitlow-growing basal rosettelow-growing basal rosetteclimbing vine
Hairinessnot or sparsely hairyvery hairynot hairy
Leavesflat or wavy edges

rounded or pointed tips
very wavy edges

pointed tips
flat edges

pointed tips
Habitatgrassland and scrubserpentine grassland and scrubchaparral, scrub, and open woodland 
Hill Morning-glory (L), Hillside Morning-glory (M), Western Morning-glory (R)
© CBowker (L), DSchiel (M), GBarton (R)

At Edgewood

  • Found in grasslands and scrub
    • See iNaturalist for observations of Calystegia subacaulis
  • Flowers April – June

See General References