Rare Plant Species Rediscovered in Presidio

Author: Michael Chasse & Marie Fontaine & Emily Magnaghi

During the past few years, some interesting plant species have been rediscovered in the Presidio’s natural areas. Most had not been recorded in San Francisco since the 1958 publication A Flora of San Francisco, California. A few hadn’t been observed here since the late 1800s. Although none of these species are considered to be rare, threatened, or endangered on the global or state levels, here in San Francisco they are uncommon members of our local flora. Thanks to the efforts of community-based stewardship, more eyes are out there to observe the full diversity of our natural areas.

Some examples of taxa recently located in the Presidio:

    Sagittaria montevidensis Cham. & Schldl. ssp. calycina (Engelm.) C. Bogin. (Montevideo arrowhead)
    This is a new record for San Francisco County. Three individual plants emerged from sandy soils along Mountain Lake after an old water tank was removed this past year. The closest Bay Area records are from Sonoma County.
    Sanicula tuberosa Torrey (tuberous sanicle)
    Approximately 30 individuals were located on thin serpentine soil at Inspiration Point in spring of 2001. Tuberous sanicle was listed as “not common” in San Francisco by Katherine Brandegee in 1892 and was never collected in San Francisco County. A winter bloomer, tuberous sanicle is rare in San Mateo County, but is common on serpentine in Marin and infrequent in Sonoma.
    Hemizonia congesta DC. ssp. luzulifolia (DC.) Babc. & H.M. Hall (hayfield tarweed)
    This species was collected in San Francisco in 1852 by N. J. Anderson and in 1881 by Parry. Brandegee reported it from Potrero and southeastern San Francisco in 1892. The type specimen, H. luzulaefolia var. fragarioides (Kellogg), came from “the vicinity of San Francisco.” Three individuals were recently (2002) located in a moist, thin-soiled serpentine prairie near Doyle Drive. [Editor’s note: I have been informed that Hemizonia congesta ssp. luzulifolia has recently been subsumed to H. c. ssp. congesta because it is not considered distinct enough to merit separate status. Explore details on Bruce Baldwin’s research and citations to original literature
    Trifolium albopurpureum Torrey & A. Gray (Indian clover)
    A healthy population of this species was located within the serpentine grasslands of Inspiration Point during the summer of 2002. The last known report of Indian clover in San Francisco was by Rattan, who collected it in 1885.
    Montia fontana L. (water montia, blinks)
    Evelina Cannon noted its presence with a collection from the southeastern part of San Francisco in 1895. Brandegee reported it in 1892 from “wet springy places” in the western and southern parts of the city. Other San Francisco specimens date from 1879. Two good-sized populations were recently (2002) located within moist, serpentine coastal prairie at Fort Scott.
    Centunculus minimus L. (false pimpernel, chaffweed)
    Kellogg and Harford collected it in 1866 and the 1890s near San Francisco. The last known San Francisco record comes from 1892; Brandegee reported it growing on “cliffs between Lobos Creek and Fort Point [where it was] very abundant about the Presidio in company of Cicendia quadrangularis.” These two species were recently located on the Presidio’s coastal bluffs, still in the company of each other, but both in low numbers.

Other new or long-lost species recently added to the Presidio’s plant inventory:

    Layia hieracioides (DC.) Hook. & Arn. (tall madia)
    Microseris douglasii (A. Gray) Schultz-Bip. (Douglas microseris)
    Guillenia lasiophylla (Hook. & Arn.) Greene (California mustard)
    Trifolium barbigerum Torrey (bearded clover)
    T. bifidum A. Gray (notched-leaf clover)
    T. macraei Hook. & Arn. (twin clover)
    Cicendia quadrangularis (Lam.) Griseb. (timwort)
    Mentha arvensis L. (marsh mint)
    Orobanche californica Cham. & Schldl. (California broom-rape)
    Orobanche fasciculata Nutt. (clustered broomrape)
    Plantago elongata Pursh. (annual coast plantain)
    Gilia clivorum (Jepson) V. Grant (purple-spot gilia)
    Potentilla rivalis Nutt. (brook cinquefoil)
    Juncus tenuis Willd. (slender rush)
    Juncus xiphioides E. Meyer (iris-leaved rush)
    Agrostis microphylla Steudel (small-leaved bent grass)

These occurrences are recorded in a recently-developed vascular plant occurrence database for the Presidio. The database stores Presidio records dating back to 19th-century collections, on up to the present. It can be viewed at the Presidio Native Plant Nursery, 1244 Appleton Street, near Fort Scott. (A public copy of this database is not yet available). For more information call the Nursery at 415-561-4868 or email Marie Fontaine at Mfontaine@ggnpa.org.