Miner’s Lettuce

Miner’s Lettuce © TCorelli

Claytonia perfoliata ssp. perfoliata
NATIVE

Description (Jepson, PlantID.net)

  • Eudicotyledon
    • Eudicots are a major lineage of flowering plants; see family for general characteristics
  • Miner’s Lettuce Family (Montiaceae)
  • Common annual herb
  • Leaves
    • Fleshy (succulent) leaves
    • In 3 sequential forms
      • First sets are blade-shaped
      • Next sets are spade-shaped
      • Finally, a fused pair creates a disk (perfoliate leaf) below the flowers
  • Flowers
    • Inflorescence (flower arrangement) is a terminal raceme (unbranched stem with stalked flowers opening from the bottom up)
    • Numerous, small, white to pink flowers
      • Emerge from the center of the perfoliate leaf
      • May or may not have a stalk
      • Small bract (modified leaf) at the base of the lowest flower covers the emerging buds
    • Ovary superior (above the attachment of other flower parts)
  • Height to 16 in.

Distribution

  • Native to California
    • Grows in seasonally damp locations in oak woodlands and coastal sage scrub
    • See Calflora for statewide observations of this plant
  • Outside California, confined to western mountain and coastal regions of North America
  • Grows at elevations to 3,280 ft.
Distinct Leaf Types © TCorelli / DSchiel

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

  • Seeds eaten by birds
  • Native people reported to place leaves near red ant nests so swarming ants would leave a vinegar taste–creating salad dressing! (Corelli 2004)
  • Eaten as a salad and boiled green (similar to spinach) by Native people, settlers, and Europeans
  • Good source of vitamin C
  • CAUTION – Contains oxalic acid and can be toxic if ingested in large quantities

Name Derivation

  • Claytonia (klay-TONE-ee-a) – named for John Clayton, an 18th-century American botanist
  • perfoliata (per-fo-lee-AY-ta)from the Latin prefix per-, “through,” and folium, “leaf,” as the stem appears to perforate the fused upper leaves
  • Miner’s lettuce – refers to California Gold Rush miners who ate it to prevent scurvy
Seeds with Elaiosomes © DSchiel

Notes

  • Happiest in a cool, damp environment; stressed leaves turn deep red
  • The white, fleshy tips on the seeds are elaiosomes, nutrient-rich food packages that attract ants
    • Ants carry the seeds back to their colony, feed the food packet to their larvae, and discard the seed, thus aiding in seed dispersal (Lengyel 2010)
    • Giant trillium (Trillium chloropetalum) is another Edgewood species that uses this strategy, called myrmecochory
  • Edgewood’s miner’s lettuce 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

At Edgewood

  • Found in woodlands and grasslands
    • See iNaturalist for observations of Claytonia perfoliata
  • Flowers February – May

See General References

Specific References

Agriculture and Natural Resources, University of California. 2019. Weed Gallery: Miner’s Lettuce–UC. State-wide Integrated Pest Management Program.

Lengyel, S. 2010. Convergent evolution of seed dispersal by ants, and phylogeny and biogeography in flowering plants: A global survey. Abstract. Perspectives in Plant Ecology, Evolution and Systematics, 12 (1): 43–55.