Taxon Report

Boechera constancei (Rollins) Al-Shehbaz

Constance's rockcress

Print Report


Taxon Summary

Boechera constancei, commonly known as Constance's rockcress, is a perennial herb in the Brassicaceae that is found only in California. It occurs within Chaparral, Lower montane coniferous forest, and Upper montane coniferous forest, growing at elevations from 975 to 2025 meters. Boechera constancei is ranked 1B.1, Plants Rare, Threatened or Endangered in California and Elsewhere; Seriously threatened in California.

  Classification
Scientific Name:
 Boechera constancei (Rollins) Al-Shehbaz
Common Name:
 Constance's rockcress
Family: Brassicaceae
Element Code: PDBRA06090
USDA Plants Symbol:
Synonyms/Other Names:
  • Arabis constancei

Ecology and Life History
Lifeform: perennial herb
Blooming Period: May-Jul May-Jul
Elevation: 975-2025 (3200-6645)
General Habitats: Chaparral, Lower montane coniferous forest, Upper montane coniferous forest
Microhabitat: Rocky, Serpentine
Microhabitat Details:

Conservation Status
CA Rare Plant Rank: 1B.1
Global Rank: G2
State Rank:
 S2
State List: None
Fed List: None
Other Status: USFS_S
CRPR Changes:

Occurrence Data from the CNDDB
Total Occurrences: 59
Element Occurrence Ranks:
   Excellent (A) 4
   Good (B) 20
   Fair (C) 3
   Poor (D) 1
   None (X) 0
   Unknown (U) 31

Location
California Endemic:  True
California Counties and Islands: Name (Code)
Plumas (PLU), Sierra (SIE)
Quads: Name (Quad Code)
Belden (4012113), Bucks Lake (3912182), Canyondam (4012121), Caribou (4012112), Crescent Mills (4012018), Greenville (4012028), La Porte (3912068), Meadow Valley (3912181), Onion Valley (3912078), Quincy (3912088), Spring Garden (3912087), Twain (4012111)

Threat List Data from the CNDDB

Threat List Total: 10
EOs with Threat Listed: Total EOs % of EOs
40 68 %
Logging 29 49%
Road/trail construction/maint. 12 20%
Mining 7 11%
Other 5 8%
Wood cutting or brush clearing 3 5%
ORV activity 3 5%
Improper burning regime 2 3%
Biocides 1 1%
Disease 1 1%
Erosion/runoff 1 1%

Notes
Threatened by road widening, logging, mining, and urbanization. Possibly threatened by vehicles. See Contributions from the Gray Herbarium 201:4-6 (1971) for original description.
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 27 January 2025].