Calochortus indecorus, superfluously named Sexton Mountain mariposa lily as it was seen and recognized by very few people, was a perennial herb in the lily family, Liliaceae, that is only known to have grown in Southern Oregon on Sexton Mountain, 10 or 15 miles north of Grants Pass, at the northern reaches of the Klamath Mountains. Botanists collected this lovely little endemic flower once on May 20, 1948 establishing the taxonomy of the species and introducing it to modern science. Unfortunately, all subsequent efforts to locate the flower were unsuccessful and it is now believed the flower’s very limited population was destroyed by human expansion, in particular the construction of Interstate-5, a major disturbance event occurring at the base of Sexton Mountain (source). Finding this plant anywhere else is highly unlikely. Only the original specimens at the Oregon State University Herbarium, remain as a dry and flattened reminder of a plant none of us will ever see.
I must admit to some favoritism in singling out this particular extinct plant for remembrance—unfortunately there is no shortage of species to choose from—as Calochortus (“beautiful grass” in Greek) is one of my favorite genera. It is a North American genus occurring mostly in the West and its flowers are consistently beautiful, both striking in their color and delicate yet simple in their form. Calochortus contains about 70 species, each has showy flowers with three petals, often hairy, colored white, yellow, blue, or violet, and with three distinct sepals. C. indecorus grew 3-5 inches tall with flowers in groups of two or three with mostly hairless bright lavender-blue petals and green sepals. It grew from a bulb each spring and was said to have bloomed in May, forming a winged-capsule fruit after being pollinated.
C. indecorus grew in a very unique habitat: the Klamath Mountains Ecoregion in the Southwest and Northwest corners of Oregon and California respectively. The ecoregion encompasses the Klamath and Siskiyou Mountain ranges and the surrounding foothills. This area is home to one of the most biodiverse floras in North America. 30 species of coniferous trees grow here, seven of which are endemic (including the beautiful Port Orford Cedar, Chamaecyparis lawsoniana). In total, at least 3,500 plant species exist in this relatively small area, many are found nowhere else. There are many reasons for this diversity, the highly divergent rainfall totals for example, and the fact that several different bioregions converge in this area, including the Coast Range, the Cascades, California’s Central Valley, the Sierra Nevada, and the Great Basin, each bringing unique species into this melting pot of a biological community (source).
The region’s complex geology, however, is perhaps most important in developing the many endemic plant species found here, especially the serpentine soil, which is rich in the heavy metals nickel and chromium, is lacking in several micronutrients important for plant growth including potassium and phosphorus, and has a very low calcium to magnesium ratio (source). Plants must evolve attributes which allow them to thrive in these stressful conditions. This also limits their range to narrow bands of similar soil which, in combination with narrow environmental bands, leads to the evolution of plants found nowhere else on earth including many found only in a single watershed or even on a single mountain. In fact, many species of Calochortus specifically, still grow in endemic communities in the greater Klamath bioregion including: C. umpquaensis (listed as vulnerable), C. persistens (listed as imperiled), C. nudus (vulnerable), C. howellii (vulnerable), C. greenei (vulnerable), and one, C. monanthus, which is also believed to be extinct.
Overgrazing of cattle, construction of roads and developments, invasive weeds, logging, poaching, fire suppression, and strip mining for nickel and other rare metals all pose significant threats to the endemic and threatened species of the Klamath and Siskiyou mountains. Fortunately, there are wilderness and protected areas in the region including the Kalmiopsis Wilderness and the recently expanded Cascade-Siskiyou National Monument, the first monument specifically designated to protect biodiversity (source). Yet there is still a need for vigilance. There are many in government and industry who would prefer to exploit this unique land rather than conserve it. We can learn an invaluable lesson from C. indecorus and other extinct plant species from the Klamath Region: disturbances which may seem small compared to the large scales typically considered in ecological protection—opening a single strip mine, allowing cattle to graze a new parcel of land, or Interstate construction, can have devastating effects on small, endemic populations. This area, more than most, needs defending. When an entire species can be lost in a single disturbance event, it is imperative that we not give an inch.