This new column is intended to familiarize our members with some of San Francisco and San Mateo counties’ rare, endangered, and otherwise unique plant species. Each issue will feature a different species. We will describe the plant’s taxonomic features, its distribution, habitat affinities, flowering times, legal protection, and current threats, as well as provide historical and other interesting information. We will also describe the efforts of chapter members and others to preserve these threatened members of our unique flora.

In October 1816 the Russian vessel Rurik landed at the Presidio during a three-year long expedition along the West Coast of North America. On board were two of California’s most famous early botanical explorers, the naturalist Adelbert von Chamisso and a surgeon by the name of Johann Friedrich Eschscholtz. Together, Chamisso and Eschscholtz collected 82 plant species at the Presidio. Chamisso ultimately named more than 30 new species from his Presidio collections. (See the January 1979 issue of Fremontia)

One of the new species that Chamisso collected and named was Lessingia germanorum. The genus was named in honor of the Lessing brothers. One of the brothers, the German botanist C.F. Lessing, was an authority on the Asteraceae (sunflower family) and studied most of Chamisso’s collections.

Today, San Francisco lessingia is one of San Francisco County’s most endangered plant species. A diffusely branching member of the sunflower family, the plant is a low erect annual growing six to 18 inches in height. It produces mostly solitary in florescences approximately one half-inch high containing 20-40 deep lemon yellow disk flowers. The outer expanded disk flowers have brownish spots in the throat. No ray flowers are present in this species or in most other species of Lessingia. The plant blooms from July through December.

San Francisco lessingia is found only on sandy flats and sand dunes close to the coast. All that remains of what is presumed to have been a common inhabitant of San Francisco’s extensive sand dune complex consists of four naturally occurring populations and one introduced stand in the Presidio and one population at the western base of San Bruno Mountain. It is entirely restricted to openings on loose shifting sands devoid of substantial shrub cover.

Lessingia germanorum is listed as endangered by the state of California, is a C-1 candidate for listing as endangered by the Federal Government, and is on the CNPS List 1B:3-3-3. Under the California Endangered Species Act, a native plant listed as endangered is one whose “prospects of survival and reproduction are in immediate jeopardy from one of more causes”. C-1 candidates for federal listing are those for which sufficient information exists to support listing as endangered or threatened by the U.S. Fish and Wildlife Service. CNPS List 1B species are those considered endangered in California and elsewhere. The 3-3-3 designation for rarity, endangerment and distribution means that the species is distributed in one to several highly restricted occurrences, endangered throughout its range and endemic to California.

Given its current status, San Francisco lessingia is protected from all impacts. Only collecting for scientific or management purposes is allowed and a permit from the state Department of Fish and Game is required.

Because San Francisco lessingia is restricted to loose sandy habitat, it is highly sensitive to disturbance resulting from off-trail foot, bicycle, horse, and vehicle traffic. However, its most serious threat appears to come from invasive shrubs and trees, which shade it out and render its habitat completely unsuitable. The remaining populations of San Francisco lessingia are currently threatened by the advance of eucalyptus and Monterey pine trees and are disturbed by foot and vehicle traffic. Chapter members are very active in assisting the National Park Service with its preservation efforts in the Presidio. Volunteers for weeding parties are always welcome – see this site’s “Habitat Restoration” page to check out work parties in the Presidio.