Sidalcea hickmanii

Greene

Chaparral Checkerbloom

G2Imperiled Found in 2 roadless areas NatureServe Explorer →
G2ImperiledGlobal Rank
HighThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.131357
Element CodePDMAL110A0
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicendemic to a single nation
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderMalvales
FamilyMalvaceae
GenusSidalcea
Other Common Names
Hickman's Mallow (EN)
Concept Reference
Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2021-09-08
Change Date2021-09-08
Edition Date2021-09-02
Edition AuthorsJoyal, E. (1988), rev. Treher (2021)
Threat ImpactHigh
Range Extent20,000-200,000 square km (about 8000-80,000 square miles)
Number of Occurrences21 - 80
Rank Reasons
Sidalcea hickmanii occurs in southern California to southwestern Oregon in the United States. There are seven described subspecies in this species that exemplify the relict nature of its distribution, as a series of widely dispersed, small, isolated populations.Three of subspecies are endemic to a single site. Sidalcea hickmanii ssp. viridis has not been seen since 1976 despite searching. See each subspecies for additional information on threats, trends, population sizes, and global ranks.
Range Extent Comments
Sidalcea hickmanii occurs in southern California to southwestern Oregon in the United States. There are seven described subspecies in this species that exemplify the relict nature of its distribution, as a series of widely dispersed, small, isolated populations. At the northern extent of the species range is Sidalcea hickmanii ssp. petraea, a single site endemic of Jackson County, Oregon.
Occurrences Comments
Three of the subspecies (Sidalcea hickmanii ssp. napensis, Sidalcea hickmanii ssp. petraea, Sidalcea hickmanii ssp. pillsburiensis) are only known from a single occurrence.
Threat Impact Comments
The subspecies are widely distributed in California and Oregon and each is subject to a different set of threats: see each for a summary of threats and a threats assessment. Fire related threats and development, may be common across the subspecies. Fire suppression allows for the advancement of woody vegetation that outcompete and shade plants. The inappropriate timing or intensity of fires may impact the species by inhibiting reproduction (USFWS 2004).
Ecology & Habitat

Habitat

Habitat of Sidalcea hickmanii subspecies includes closed-cone conifer forests, chaparral, cis/montane woodlands, open conifer forests, and pine-oak-Ceanothus-Cercocarpus-Toxicodendron association; substrates include serpentine, rocky, rhyolitic, volcanic soil, and rocky sandstone (Flora of North America Editorial Committe 2010).
Terrestrial Habitats
Forest/WoodlandForest - ConiferWoodland - MixedShrubland/chaparral
Other Nations (1)
United StatesN2
ProvinceRankNative
CaliforniaSNRYes
OregonSNRYes
Threat Assessments
ThreatScopeSeverityTiming
1 - Residential & commercial developmentUnknownExtreme - seriousHigh (continuing)
7 - Natural system modificationsPervasive - largeUnknownHigh (continuing)
7.1 - Fire & fire suppressionPervasive - largeUnknownHigh (continuing)

Plant Characteristics
Economic Value (Genus)No
Roadless Areas (2)
California (2)
AreaForestAcres
Greenhorn CreekSequoia National Forest28,226
Mill CreekSequoia National Forest27,643
References (2)
  1. Flora of North America Editorial Committee (FNA). 2015. Flora of North America north of Mexico. Vol. 6. Magnoliophyta: Cucurbitaceae to Droserceae. Oxford University Press, New York. 496 pp + xxiv.
  2. Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.