Taxon Report

Lasthenia conjugens Greene

Contra Costa goldfields

Print Report


© 2013 Neal Kramer

  Classification

Scientific Name:
Lasthenia conjugens Greene
Common Name:
Contra Costa goldfields
Family: Asteraceae
Element Code: PDAST5L040
USDA Plants Symbol: LACO6
Synonyms/Other Names:

Ecology and Life History

Lifeform: annual herb
Blooming Period: Mar-Jun Mar-Jun
Elevation: 0-470 (0-1540)
General Habitats: Cismontane woodland, Playas, Valley and foothill grassland, Vernal pools
Microhabitat: Mesic
Microhabitat Details:

Occurrence Data from the CNDDB

Total Occurrences: 36
Element Occurrence Ranks:
   Excellent (A) 2
   Good (B) 12
   Fair (C) 1
   Poor (D) 0
   None (X) 11
   Unknown (U) 10
California Endemic:  True
California Counties and Islands: Name (Code)
Alameda (ALA), Contra Costa (CCA), Marin (MRN), Mendocino (MEN)*, Monterey (MNT), Napa (NAP), Santa Barbara (SBA)*, Santa Clara (SCL)*, Solano (SOL), Sonoma (SON)
Quads: Name (Quad Code)
Antioch North (3812117), Antioch South (3712187), Benicia (3812212), Capell Valley (3812242)*, Cuttings Wharf (3812223), Denverton (3812128), Dos Pueblos Canyon (3411948), Elmira (3812138), Fairfield North (3812231), Fairfield South (3812221), Goleta (3411947)*, Marina (3612167), Milpitas (3712148), Napa (3812233), Newark (3712251)*, Petaluma River (3812225), Point Arena (3812386)*, Salinas (3612166), San Jose East (3712137)*, San Leandro (3712262), Seaside (3612157), Valley Ford (3812238), Walnut Creek (3712281)*

Threat List Data from the CNDDB

Threat List Total: 14
EOs with Threat Listed: Total EOs % of EOs
25 69 %
Development 13 36%
Grazing 8 22%
Non-native plant impacts 7 19%
Disking 4 11%
Agriculture 3 8%
Other 3 8%
Feral pigs 2 5%
Altered flood/tidal/hydrologic regime 2 5%
ORV activity 2 5%
Landfill 1 2%
Military operations 1 2%
Erosion/runoff 1 2%
Recreational use (non-ORV) 1 2%
Wood cutting or brush clearing 1 2%

Notes

Many historical occurrences extirpated by development and agriculture. Currently threatened by development, habitat alteration, hydrological alterations, overgrazing, and non-native plants. See Pittonia 1:221 (1888) for original description, and MadroƱo 50(2):83-93 (2003) for ecological information.
Threats:
Taxonomy:
Citation California Native Plant Society, Rare Plant Program. 2024. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 25 December 2024].