Sidalcea oregana subsp. valida
Kenwood marsh checkerbloom, Kenwood Marsh Checkerbloom
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Family: Malvaceae · Type: Subshrub · Native
Conservation status: CNPS 1B.1 · Endangered
Sidalcea oregana subsp. valida (Kenwood marsh checkerbloom) is a native California subshrub in the Malvaceae family, recognized by thick fleshy roots and robust decumbent stems.
Kenwood marsh checkerbloom is a rare (CNPS 1B.1) California native perennial found in southern North Coast Ranges near Kenwood in Sonoma County, inhabiting marsh environments at approximately 150 meters elevation. Flowering from June to September, this plant produces pink-lavender flowers 10 to 15 millimeters long in dense, compact clusters. Growing 90 to 120 centimeters tall with multiple decumbent stems that often root near the base and have thick, fleshy roots, it develops stems more than 5 millimeters in diameter with sparse bristles. Its leaves are covered with stellate (star-shaped) hairs, with stems becoming relatively smooth with age as they mature. The fruit segments are smooth, approximately 3 millimeters long with a short 0.5-millimeter beak.
Identification and appearance
Key characters: 10 sympatric species; thick fleshy roots and robust decumbent stems
Habitat and range
Habitat: Marsh
Elevation: +- 150 m.
Bloom period
Sidalcea oregana subsp. valida blooms Jun-Sep.
Conservation status
CNPS 1B.1 · Endangered
How to tell it apart
vs Malva: Sidalcea has no bract ring below flowers and anthers in two circles; Malva has 3 bracts and scattered anthers.; vs Clarkia: Sidalcea has mallow flowers with fused stamens; Clarkia has 4 separate petals and 8 separate stamens.; vs Geranium: Sidalcea has bowl-shaped flowers with fused stamens; Geranium has 5 separate petals and long beaked fruits.; vs Malacothamnus: Sidalcea is herbaceous in meadows; Malacothamnus is a woody shrub in chaparral.; vs Calochortus: Sidalcea is a dicot with 5-petaled flowers; Calochortus is a monocot with 3-petaled flowers from bulbs.
Frequently asked questions
Is Sidalcea oregana subsp. valida native to California?
Yes. Sidalcea oregana subsp. valida is native to California (recorded as native).
When does Sidalcea oregana subsp. valida bloom?
Sidalcea oregana subsp. valida blooms Jun-Sep.
What plant family does Sidalcea oregana subsp. valida belong to?
Sidalcea oregana subsp. valida is in the Malvaceae family, genus Sidalcea.
Is Sidalcea oregana subsp. valida rare or endangered?
Sidalcea oregana subsp. valida carries California Rare Plant Rank 1B.1, state rank S1.
What habitat does Sidalcea oregana subsp. valida grow in?
Sidalcea oregana subsp. valida grows in Marsh.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos · CDFW CNDDB
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.