Taxon Report

Deinandra minthornii (Jeps.) B.G. Baldwin

Santa Susana tarplant

Print Report


Taxon Summary

Deinandra minthornii, commonly known as Santa Susana tarplant, is a perennial deciduous shrub in the Asteraceae that is found only in California. It occurs within Chaparral, and Coastal scrub, growing at elevations from 280 to 760 meters. Deinandra minthornii is ranked 1B.2, Plants Rare, Threatened or Endangered in California and Elsewhere; Moderately threatened in California.


  Classification

Scientific Name:
Deinandra minthornii (Jeps.) B.G. Baldwin
Common Name:
Santa Susana tarplant
Family: Asteraceae
Element Code: PDAST4R0J0
USDA Plants Symbol: DEMI4
Synonyms/Other Names:
  • Hemizonia minthornii Jeps.

Ecology and Life History

Lifeform: perennial deciduous shrub
Blooming Period: Jul-Nov Jul-Nov
Elevation: 280-760 (920-2495)
General Habitats: Chaparral, Coastal scrub
Microhabitat: Rocky
Microhabitat Details:

Occurrence Data from the CNDDB

Total Occurrences: 38
Element Occurrence Ranks:
   Excellent (A) 6
   Good (B) 11
   Fair (C) 3
   Poor (D) 0
   None (X) 0
   Unknown (U) 18
California Endemic:  True
California Counties and Islands: Name (Code)
Los Angeles (LAX), Ventura (VEN)
Quads: Name (Quad Code)
Calabasas (3411826), Canoga Park (3411825), Malibu Beach (3411816), Oat Mountain (3411835), Point Dume (3411817), Santa Susana (3411836), Thousand Oaks (3411827), Topanga (3411815), Triunfo Pass (3411818)

Threat List Data from the CNDDB

Threat List Total: 10
EOs with Threat Listed: Total EOs % of EOs
19 50 %
Development 12 31%
Road/trail construction/maint. 6 15%
Wood cutting or brush clearing 5 13%
Recreational use (non-ORV) 4 10%
Foot traffic/trampling 3 7%
Improper burning regime 3 7%
Non-native plant impacts 3 7%
Grazing 2 5%
Vandalism/dumping/litter 2 5%
Other 1 2%

Notes

Threatened by development. Possibly threatened by non-native plants. State-listed as Hemizonia minthornii; see this name in The Jepson Manual. See Manual of the Flowering Plants of California, p. 1092 (1925) by W.L. Jepson for original description, and Novon 9:462-471 (1999) for revised nomenclature.
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 3 February 2025].