MARIN COUNTY STATE AND/ OR FEDERALLY LISTED RARE, THREATENED OR

ENDANGERED PLANTS, AS OF JULY 2008.

Locations are given of present populations of the plants, or the last reported location if presumed

extirpated. There have been few changes in our list in several years for several reasons. Science is

often trumped by expediency, lack of sufficient documentation and sponsors. Some of these taxa are

now discovered to be locally abundant because new populations have been found since listing, while

others have been reduced over time to a few individuals only.

Codes: S= State listing, F= Federal listing, R= Rare, T= Threatened, E= Endangered

1. Alopecurus aequalis var. sonomensis, Sonoma alopecurus, grows in wetlands, FE, only on

PRNS.

2. Blennosperma nanum var. robustum, Pt. Reyes blennosperma, SR, can be very abundant,

PRNS.

3. Calochortus tiburonensis, Tiburon mariposa lily, ST, near Corte Madera, uplands, serpentine

substrate.

4. Castilleja affinis ssp. neglecta, Tiburon paintbrush, ST, Corte Madera and Tiburon peninsula, S.

of Nicasio reservoir , serpentine uplands.

5. Ceanothus masonii, SR,Mason’s ceanothus, Bolinas Ridge uplands, on sandstone, very few

plants.

6. Chorizanthe valida, SE, Sonoma spineflower, sandy flats, Lunny “G” Ranch, PRNS.

7. Cordylanthus mollis ssp. mollis, SR, FE, soft bird’s-beak, near Gnoss Field airport, saltmarsh

(probably extirpated).

8. Delphinium bakeri, Baker's larkspur, SE, one roadside site, few plants left, along the Petaluma-

Marshall Road.

9. Delphinium luteum, yellow larkspur, SR, it grows near Tomales along the roadside bluffs.

10. Hesperolinon congestum, Marin western flax ST, FT, Tiburon Peninsula, Mt. Tamalpais, Big

Rock Ridge and Mt. Burdell,

11. Holocarpha macradenia,, Santa Cruz tarplant, SE , FT, it grew in the Ross Valley (probably

extirpated).

12. Lasthenia conjugens Contra Costa goldfields, FE, just E. of Highway 1 at Marin /Sonoma Co. line.

13. Layia carnosa, beach layia, SE, FE, abundant, PRNS new sand dunes.

14. Limnanthes douglasii var. sulphurea, Pt. Reyes meadowfoam, SE, only on PRNS, roadside ditches

and marshes.

15. Lupinus tidestromii, Tidestrom's lupine, SE, FE, PRNS, new sand dunes.

16. Pentachaeta bellidiflora, white-rayed pentachaeta, Se, FE, last seen on the San Quentin peninsula in

the 1970's, (probably extirpated).

17. Pleuropogon hooverianus, Hoover’s semaphore grass SE, one roadside site near the San Geronimo

water-treatment plant.

18. Streptanthus niger, SE, FE, Tiburon jewel flower, southern tip of Tiburon peninsula.

19. Trifolium amoenum, FE, showy Indian clover, Dillon Beach/ Oceana Marin, on a cliff edge.

If you rediscover any of Marin “extirpated” plants or new locations for others, please contact Doreen Smith of Marin Chapter CNPS ph. 415-479-7888.

Further information on California rare, threatened and endangered plants, and the CNPS listings of rare plants, can be accessed via the North Coast Chapter CNPS website under “DATABASES”.