Checker Mallow

Dwarf Checkerbloom
Sidalcea malviflora ssp. malviflora
NATIVE

Description (Jepson, PlantID.net)

• Eudicotyledon
  • Eudicots are a major lineage of flowering plants; see family for general characteristics
• Mallow Family (Malvaceae)
• Perennial herb
  • Generally grows from rhizomes (horizontal underground stems)
  • Whole plant coarsely to bristly hairy, especially at base
• Stems
  • Decumbent (lying on the ground before ascending)
• Leaves
  • Alternate (1 leaf at each junction with stem) and simple (not divided into leaflets)
  • 2 types
    • Lower leaves rounded and shallowly lobed
    • Upper leaves usually more deeply lobed
  • Coarsely hairy on both sides and fleshy
  • Stipules (pair of leaf-like structures at the base of the leaf stalk) are undivided
• Flowers
  • Inflorescence (flower arrangement) is a raceme (unbranched stem with stalked flowers opening from the bottom up) with evenly spaced flowers
    • Short pedicels (stalks of single flowers in a cluster) make the inflorescence appear a spike (an unbranched stem with stalkless flowers)
    • Bracts (modified leaves) at base are short (≤ 0.2 in.), leaflike, and undivided
  • Each cup-shaped flower has 5 free petals
    • Pink to rose, with white veins
    • Splays in age
  • 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 24 in.

Distribution

• Native to California
  • Grows in coastal prairie, open forests, and scrub
  • See Calfora for statewide observations of this plant
• Outside California, grows in Oregon
• Grows at elevations to 1,650 ft.

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

• Wildlife
  • Pollen and nectar source for native bees
  • Nectar source and larval food source (host) for butterflies, i.e. gray hairstreak (Strymon melinus), common checkered-skipper (Pyrgus communis), two-banded checkered-skipper (P. ruralis), painted lady (Vanessa cardui), and West Coast lady (V. annabella)
• Native people
  • Plant eaten after steaming in an earth oven
  • Dried leaves used as a spice in manzanita berry preparations
  • Infusion used for treating internal injuries

Name Derivation

• Sidalcea (si-DAL-see-a) – from Sida and Alcea, names of related genera in the Mallow family
  • Both Sida and Alcea are Greek names for mallow
• malviflora (mal-vi-FLOR-a) – from the Latin malva “mallow” and flora “flowers,” for the mallow-like flowers
  • Malva comes from the Greek malache “to soften,” referring to the leaves and a soothing skin ointment made from the seeds of mallows (Malva species), also in the Mallow family (Malvaceae)
• Checker mallow – as with the name checkerbloom, commonly used for plants in the genus Sidalcea, referring to the pattern of veins on the petals of some species

Notes

• Geophytes, e.g. plants growing from bulbs, corms, and rhizomes, are 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
• Flowers close at night or when it’s cloudy (Lady Bird 2007)
  • This process is an example of photonasty, a nastic response to light
  • Nastic responses occur when a plant part, such as a flower or leaf, moves in response to a stimulus (Mauseth 2012), e.g., humidity (hydronasty), light (photonasty), temperature (thermonasty), or touch (thigmonasty)
    • Nastic responses are caused by changes in turgor pressure 
    • They are independent of the direction of the stimulus and usually are reversible and repeatable
  • Nastic responses differ from tropic responses
    • Tropic responses are directional growth movements—a plant grows toward or away from a stimulus, e.g., light (phototropism), gravity (gravitropism) or touch (thigmotropism)
    • All plants have tropic responses, but only some plants have nastic responses
• Checker mallow is highly variable throughout its range with many subspecies (Lady Bird 2007)
  • Subspecies indicates a geographically-separated population with distinct morphological characteristics; when not isolated, interbreeding is possible
  • Variety indicates a population with small morphological variations, e.g. color, seen throughout the geographic range of the species; interbreeding is possible
  • In practice, botanists have not consistently applied these ranks
  • Jepson notes that the subspecies malviflora, found at Edgewood, “probably has been the [subspecies] most damaged or modified by coastal development, resulting in local extinctions or intermediate forms

ID Tips

• May be confused with fringed checker bloom (S. diploscypha) also in the Mallow family

	Checker Mallow	Fringed Checker Bloom
Growth Habit	perennial	annual
Habitat	non-serpentine grasslands	serpentine grasslands
Flowers
Shape	cup-shaped, splaying in age … petals usually overlap at base	cup-shaped … petals narrow, creating 5 tiny “windows”
Color	pink to rose	pink, with white base
Bracts¹	short (≤ 0.2 in.) … leaflike and undivided	long (≤ 0.4 in.) … frilly, divided into 2-4 narrow lobes
Spacing	clusters more evenly spaced	clusters crowded
Stipules²	undivided	divided into narrow lobes
Blooming Period	early spring (grasses green)	late spring (grasses brown)

At Edgewood

• Found in grasslands
  • See iNaturalist for observations of this plant (S. malviflora)
• Flowers February – June

Specific References

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

Lady Bird Johnson Wildflower Center. 2007. Sidalcea malviflora. Plant Database. University of Texas at Austin.

Mauseth, J. 2012. Botany: An Introduction to Plant Biology (5th ed.). Jones & Bartlett Learning. Burlington, Massachusetts.

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.

General References

Calflora Database. 2014. Berkeley, California.

Calscape. 2018. California Native Plant Society.

Charters, M.L. 2015. California Plant Names: Latin and Greek Meanings and Derivations.

Charters, M.L. 2017. Southern California Wildflowers: Guide to the Pronunciation of Specific, Generic and Family Names.

Corelli, T. 2004. Flowering Plants of Edgewood Natural Preserve (2nd. ed.). Monocot Press, Half Moon Bay, California.

Dave’s Garden.

Elpel, T.J. 2013. Botany in a Day: The Patterns Method of Plant Identification. HOPS Press, Pony, Montana.

Flora of North America. efloras.org.

Harris, J.G., and M.W. Harris. 2013. Plant Identification Terminology: An Illustrated Glossary. Spring Lake Publishing, Spring Lake, Utah.

Keator, G. 2009. California Plant Families. University of California Press, Berkeley and Los Angeles, California.

Native American Ethnobotany DB.

Regents of the University of California. Jepson eFlora. Jepson Herbarium. University of California, Berkeley.