California Manroot

California Manroot Male Flowers © KKorbholz

Wild Cucumber
Marah fabacea

Description (Jepson,

  • Eudicotyledon
    • Eudicots are a major lineage of flowering plants; see family for general characteristics
  • Gourd / Cucumber Family (Cucurbitaceae)
  • Perennial, herbaceous, tendril-bearing vine
    • Grows from a large tuberous root
  • Large leaves are palmately lobed (lobes radiating from a single point)
  • Flowers
    • Star-shaped, white to cream-colored flowers, with 5 fused petals
    • Separate male and female flowers on the same plant (monoecious)
      • White male (staminate) flowers in a raceme (unbranched stem with stalked flowers opening from the bottom up) or panicle (branching stem with flowers opening from the bottom up)
      • Larger, solitary female flowers at the leaf axil (branching point)
    • Ovary inferior (below the attachment of other flower parts)
  • Fruit is a spherical, golf-ball-sized capsule (a dry, multi-chambered fruit that splits open at maturity) covered with straight prickles (extensions of the epidermis), containing 4 or more large seeds
    • Internal pressure builds in the mature capsule, splitting and expelling seeds
    • The explosive release of seeds from a pod is called ballochory
  • Vine extends to 20 ft.


  • Native and endemic (limited) to California
    • Most widespread Marah species in California, found within the range of almost all other native manroot species
    • Grows in woodlands and chaparral with seasonally moist soil
    • See Calflora for statewide observations of this plant
  • Grows at elevations to 5,250 ft.
Male Flowers (L), Female Flower (LM), Fruit (RM), Seeds (R)
© DSchiel / KKorbholz

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

  • Nectar source for the green hairstreak butterfly (Callophrys rubi)
  • Native people had a variety of non-edible uses for manroot
    • Seeds, which contain soap-like saponins, were crushed and thrown in slow streams, immobilizing fish by blocking oxygen intake, thus making them easier to catch
    • Seeds also used for decoration or ground to make face paint/mascara
    • To prevent baldness, the Kashaya Pomo applied to the scalp a mixture of the pounded raw root, pounded California bay fruit, and skunk grease (Native American Ethnobotany)
  • CAUTION – all parts of plant are POISONOUS
    • The alternative common name, wild cucumber, may suggest a similarity to the familiar edible cucumber (Cucumis sativus); however, Marah fabacea is NOT EDIBLE
    • Liquid inside fruit is an eye irritant
    • Use caution if handling the dried fruit as spines may irritate the skin

Name Derivation

  • Marah (Mar-ah) – from the Hebrew for “bitter,” likely a biblical reference to Marah, a place with undrinkable water visited by the Israelites during the Exodus; here, referring to the plant’s bitter taste
  • fabacea (fab-AY-see-a) – from the Latin for “broad bean”
  • Manroot – referring to the mature tuber, which can be as large as a man’s torso
Tendrils © DSchiel


  • Plant appears following winter rains, then dies back completely, becoming dormant during the dry summer and fall months
  • Long tendrils enable plant to climb/trail over vegetation
  • Once a tendril curls around a support, it forms a counter-clockwise helix and clockwise helix with a straight section between the two. If the tendril is pulled, more turns are added to both helices to better grasp the support (Perry 2012)
  • Mature tuber-like root is several ft. in diameter, weighing over 150 lbs., with swollen lobes and arm-like extensions
    • The root of a Marah macrocarpa, a related species, at Rancho Santa Ana Botanic Garden, weighed 467 lbs.
  • Pollinated by insects but can also self-pollinate

ID Tips

At Edgewood

  • Found in chaparral and woodlands
  • Flowers March – April

See General References

Specific References

    Perry, C. 2012, Aug. 30. Uncoiling the cucumber’s enigma. School of Engineering and Applied Sciences, Harvard University.

      Sigg, J. 2012, Feb. 6. Cool as a Cucumber. Bay Nature.