Taxon Report

Chlorogalum grandiflorum Hoov.

Red Hills soaproot

Print Report


Taxon Summary

Chlorogalum grandiflorum, commonly known as Red Hills soaproot, is a perennial bulbiferous herb in the Agavaceae that is found only in California. It occurs within Chaparral, Cismontane woodland, and Lower montane coniferous forest, growing at elevations from 245 to 1690 meters. Chlorogalum grandiflorum is ranked 1B.2, Plants Rare, Threatened or Endangered in California and Elsewhere; Moderately threatened in California.


  Classification

Scientific Name:
Chlorogalum grandiflorum Hoov.
Common Name:
Red Hills soaproot
Family: Agavaceae
Element Code: PMLIL0G020
USDA Plants Symbol: CHGR3
Synonyms/Other Names:

Ecology and Life History

Lifeform: perennial bulbiferous herb
Blooming Period: (Apr)May-Jun (Apr)May-Jun
Elevation: 245-1690 (805-5545)
General Habitats: Chaparral, Cismontane woodland, Lower montane coniferous forest
Microhabitat: Gabbroic, Serpentine
Microhabitat Details: other soils

Occurrence Data from the CNDDB

Total Occurrences: 137
Element Occurrence Ranks:
   Excellent (A) 7
   Good (B) 41
   Fair (C) 19
   Poor (D) 5
   None (X) 0
   Unknown (U) 65
California Endemic:  True
California Counties and Islands: Name (Code)
Amador (AMA), Calaveras (CAL), El Dorado (ELD), Placer (PLA), Tuolumne (TUO)
Quads: Name (Quad Code)
Aukum (3812056), Chinese Camp (3712074), Clarksville (3812161), Colfax (3912018), Coloma (3812078), Devil Peak (3812085), Devils Nose (3812044), Dorrington (3812033), Foresthill (3912017), Fort Mountain (3812034), Garden Valley (3812077), Georgetown (3812087), Greek Store (3912015), Greenwood (3812088), Michigan Bluff (3912016), New Melones Dam (3712085), Omo Ranch (3812055), Pilot Hill (3812171), Pine Grove (3812046), Pollock Pines (3812075), Rail Road Flat (3812035), Riverton (3812074), Robbs Peak (3812084), Salt Spring Valley (3812016), Shingle Springs (3812068), Slate Mtn. (3812076), Sonora (3712084), Tunnel Hill (3812086), West Point (3812045)

Threat List Data from the CNDDB

Threat List Total: 15
EOs with Threat Listed: Total EOs % of EOs
68 50 %
Logging 31 22%
Road/trail construction/maint. 25 18%
Other 17 12%
Development 11 8%
Non-native plant impacts 10 7%
ORV activity 4 2%
Mining 4 2%
Biocides 4 2%
Grazing 4 2%
Vandalism/dumping/litter 3 2%
Wood cutting or brush clearing 3 2%
Erosion/runoff 2 1%
Foot traffic/trampling 2 1%
Disking 1 0%
Recreational use (non-ORV) 1 0%

Notes

Threatened by development, mining, road construction, and vehicles. Possibly threatened by trail maintenance, logging and non-native plants. See Leaflets of Western Botany 2(8):128 (1938) for original description.
Threats:
Taxonomy:
Citation California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 14 February 2025].