Taxon Report

Centromadia pungens (H. & A.) Greene ssp. laevis (Keck) B.G. Baldwin

smooth tarplant

Print Report


Taxon Summary

Centromadia pungens ssp. laevis, commonly known as smooth tarplant, is a annual herb in the Asteraceae that is found only in California. It occurs within Chenopod scrub, Meadows and seeps, Playas, Riparian woodland, and Valley and foothill grassland, growing at elevations from 0 to 640 meters. Centromadia pungens ssp. laevis is ranked 1B.1, Plants Rare, Threatened or Endangered in California and Elsewhere; Seriously threatened in California.

  Classification
Scientific Name:
 Centromadia pungens (H. & A.) Greene ssp. laevis (Keck) B.G. Baldwin
Common Name:
 smooth tarplant
Family: Asteraceae
Element Code: PDAST4R0R4
USDA Plants Symbol: CEPUL
Synonyms/Other Names:
  • Hemizonia pungens (H. & A.) T. & G. ssp. laevis Keck

Ecology and Life History
Lifeform: annual herb
Blooming Period: Apr-Sep Apr-Sep
Elevation: 0-640 (0-2100)
General Habitats: Chenopod scrub, Meadows and seeps, Playas, Riparian woodland, Valley and foothill grassland
Microhabitat: Alkaline
Microhabitat Details:

Conservation Status
CA Rare Plant Rank: 1B.1
Global Rank: G3G4T2
State Rank:
 S2
State List: None
Fed List: None
Other Status: BLM_S; SB_CalBG/RSABG
CRPR Changes:

Occurrence Data from the CNDDB
Total Occurrences: 137
Element Occurrence Ranks:
   Excellent (A) 2
   Good (B) 13
   Fair (C) 25
   Poor (D) 9
   None (X) 14
   Unknown (U) 74

Location
California Endemic:  True
California Counties and Islands: Name (Code)
Los Angeles (LAX), Riverside (RIV), San Bernardino (SBD), San Diego (SDG)
Quads: Name (Quad Code)
Alberhill (3311764), Anza (3311656), Bachelor Mtn. (3311751), Beaumont (3311688), Bonsall (3311732), Borrego Sink (3311623)*, Corona North (3311785), El Cajon (3211678)*, El Casco (3311781), Escondido (3311711), Harrison Mtn. (3411722)*, Hemet (3311668), Lake Elsinore (3311763), Lake Mathews (3311774), Lakeview (3311771), Las Pulgas Canyon (3311734), Morro Hill (3311733), Murrieta (3311752), Oceanside (3311724)*, Pasadena (3411822), Perris (3311772), Prado Dam (3311786), Redlands (3411712), Riverside East (3311783), Romoland (3311762), San Bernardino North (3411723), San Bernardino South (3411713)*, San Jacinto (3311678), San Luis Rey (3311723)*, San Pasqual (3311618), San Pedro (3311863), Steele Peak (3311773), Sunnymead (3311782), Temecula (3311742), Torrance (3311873), Warners Ranch (3311626), Wildomar (3311753), Winchester (3311761)

Threat List Data from the CNDDB

Threat List Total: 15
EOs with Threat Listed: Total EOs % of EOs
77 56 %
Development 45 32%
Other 24 17%
Agriculture 20 14%
Disking 18 13%
Road/trail construction/maint. 16 11%
Grazing 13 9%
ORV activity 10 7%
Altered flood/tidal/hydrologic regime 9 6%
Non-native plant impacts 6 4%
Dam/Inundation 5 3%
Vandalism/dumping/litter 2 1%
Wood cutting or brush clearing 1 0%
Recreational use (non-ORV) 1 0%
Channelization 1 0%
Foot traffic/trampling 1 0%

Notes
Many historical occurrences may be extirpated; need information. Frequently confused with other Centromadia species such as C. parryi ssp. australis in ORA, LAX, and SDG cos., and C. pungens ssp. pungens in KRN Co. Need historical quads for ORA Co. Threatened by foot traffic, agriculture, road maintenance, disking, urbanization, hydrological alterations, and flood control projects. A synonym of Hemizonia pungens ssp. laevis in TJM (1993). See Madroño 3:14 (1935) for original description, and Novon 9:462-471 (1999) for revised nomenclature.
Threats:
Taxonomy:

Selected References

Citation California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 9 May 2025].