Centaurea calcitrapa  L.

Ubiquity:  Common

Distritution: Throughout excpet Napa Marsh

Plant Communities: Many,  including Ruderal

Habitats: Dry, sunny, (marshy?), weedy waste areas; & disturbed places like pastures; in most geologic formations except serpentine

Elevations: 10-2500'

Comments: Non-native.  Noxious weed

Updated:  2/25/98

Centaurea cyanus  L.

Ubiquity:  Uncommon except in landscapes

Distritution:  W1/2 except Napa Marsh.

Plant Communities: Various, including Ruderal

Habitats: Dry, sunny disturbed places like roadsides/cultivated areas like landscapes; in most geologic formations except serpentine

Elevations: 100-1600'

Comments:  Non-native; escaped exotic

Updated:  2/25/98

Centaurea iberica  Spreng./Trev.?

Ubiquity: Very uncommon 

Distritution: Known only from the bed of Putah Creek above Berryessa Estates

Plant Communities: Riparian

Habitats: Moist, sunny, gravelly, sub-barren creekbeds; in an alluvial formation

Elevation: 500'

Comments: Non-native. Collection needed

Updated:  2/25/98

Centaurea melitensis  L.

Ubiquity:  Common

Distritution: Throughout except Napa Marsh

Plant Communities: Many, including Ruderal

Habitats: Dry, sunny, grassy slopes/canyons/fields/waste areas; & disturbed places like fields/pastures/roadsides/ & cultivated areas; in most geologic formations including serpentine

Elevations: 20-2500'

Comments:  Non-native

Updated: 2/25/98

Centaurea solstitialis  L.

Ubiquity:  Very common

Distritution: Throughout

Plant Communities: Most including Ruderal

Habitats: Dry, sunny, grassy or weedy fields/slopes/islands/basins/streamsides/pondsides/streambeds/ & dikes; disturbed places like pastures/roadsides/ & cultivated areas like fields; on most geologic formations including serpentine

Elevations: 10-2500'

Comments: Non-native.  Noxious, invasive weed

Updated:  2/25/98