Western Columbine (Aquilegia formosa)

A favorite component of the lush gardens of Europe and the eastern states are the columbines. Fancied for their lacy foliage and exquisite blossoms, the columbines are hardy perennials that add springtime excitement to woodland settings. With two-inch to three-inch long flowers in shades of blue, red and orange, with contrasting, backward-pointed spurs, columbines produce abundant and unique blossoms. The nectar-bearing spurs are very attractive to hummingbirds. Horticulturists tend to think only of the European strains, but there are about 18 species native to North America, including the state flower of Colorado (A. caerulea).

Columbine is a member of the crowfoot or buttercup family (Ranunculaceae), consisting of annual and perennial herbs, vines and even low shrubs, and includes completely aquatic species. The family includes some 1,700 species belonging to 60 genera with a worldwide distribution, but centered in temperate and cold regions of both hemispheres. Members of the family exhibit a wide array of flower structures with a wide variety of pollination modes. Most flowers are insect pollinated although some are wind pollinated; most annual species are self-pollinated. Other well-known genera include Anemone, Delphinium, Clematis, Helleborus, Thalictrum, Myosurus, and, of course, Ranunculus. Members of the family are not of great economic importance, although many genera are valued ornamentals. Some genera are highly poisonous, containing toxins such as Protoanemonin, alkaloids and glycosides. Early accounts of deaths are attributed to Aconitum, whose tubers were mistaken for Jerusalem artichokes (Helianthus tuberosus).

The genus Aquilegia consists of perennial herbs developing from a caudex (a thickened, modified stem at or below ground level). It is distinguished from other members of the family by its radial flowers and petals with long, backward-pointing spurs. There are some 70 species in the genus, found in temperate North America and Eurasia. Twenty species are native to the United States. California supports three native species with another two species whose taxonomic status is unresolved.

Western columbine has a wide distribution, occurring from Alaska southward through the western United States and into Baja California, Mexico. According to the Flora of North America, western columbine includes three varieties recorded; The Jepson Manual and the Jepson Online Interchange do not currently recognize the subspecific taxa.

Western columbine is distinguished from the other California members of the genus by its red sepals, yellow petals with straight to incurved spurs. Flowering occurs April through June. It grows up to a meter and a half tall (five feet) and is an inhabitant of streambanks, seeps, chaparral, oak woodland and mixed evergreen or coniferous forests. It can be found throughout the California Floristic Province, also referred to as “cismontane” California. This geographic unit refers to lands west of the crest of the Sierra Nevada and the western edge of the Great Basin in the north and the Mojave Desert in the south. (For a more detailed discussion of California’s system of geographic units, see The Jepson Manual [Hickman 1993]). Western columbine has been recorded from 46 of California’s 58 counties. Locally, it occurs in all nine of the San Francisco Bay Area counties.

According to A Flora of San Francisco, California (Howell, et al. 1958), western columbine was known from San Francisco as a single specimen collected in 1895, although they report that in her publication, “Catalogue of the Flowering Plants and Ferns Growing Spontaneously in the City Of San Francisco,” Katherine Brandegee (1891) inferred that it was rather widespread. Nowadays, western columbine is restricted to Glen Canyon Park, the nearby O’Shaughnessy Hollow, and possibly Mt. Davidson; it is not present in the Presidio. Western columbine is considered uncommon on nearby San Bruno Mountain, and is recorded from Bitter Cherry Ridge (McClintock et al. 1990). It is considered common in the East Bay and Marin County, Montara Mountain, and the Santa Cruz Mountains. Although rare in San Francisco, the numbers of western columbine are increasing thanks to the propagation efforts of the CNPS and the Natural Areas Program.

Justifiably so, western columbine is not included in the CNPS Inventory of Rare and Endangered Plants (CNPS 2009). However, because it is seen so infrequently in San Francisco County, western columbine appears on our chapter’s list of locally significant plant species. Next spring, as you are exploring any of San Francisco’s parks and natural areas, be sure to look for the eye-catching blossoms of western columbine. And if you find it, let us know when and where it was spotted.

References:
Brandegee, K. 1891. Catalogue of the Flowering Plants and Ferns Growing Spontaneously in the City of San Francisco. Zoe II 91:334-386.
California Native Plant Society (CNPS). 2009. Inventory of Rare and Endangered Plants (online edition, v7-06d). California Native Plant Society. Sacramento, California. Available online at http://www.cnps.org/inventory.
Hickman, J.C. 1993. The Jepson Manual: Higher Plants of California. Univ. of California Press, Berkeley, California. 1400 pp.
Howell, J.T., P.H. Raven, and P. Rubtzoff. 1958. A Flora of San Francisco, California. Univ. of San Francisco. 157 pp.
McClintock, E., P. Reeberg, and W. Knight. 1990. A Flora of the San Bruno Mountains. California Native Plant Society, Sacramento, California Special Publ. No. 8. 223 pp.

Posted in Focus on Rarities.

Michael Wood

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