Search / Plant Profile / Calochortus coxii

Plant Profile

Cox's Mariposa Lily (Calochortus coxii)

Calochortus coxii is a sight to behold. Photo Credit: Fredricks

Global Rank: G1 - Critically Imperiled
Legal Status: N/A
Family: Liliaceae
State: OR
Nature Serve ID: 129513
Lifeform: Forb/herb
Date Inducted in National Collection: 03/05/1993

Description:

When the crinite mariposa lily is not in bloom, it can be difficult to distinguish from grasses and is easily overlooked. Perhaps for this reason it was not discovered until the spring of 1988. However, this plant is akin to the ugly ducking that matures into a swan, as reproductive plants are graced with attractive, white, cup-shaped flowers each spring. The Calochortus genus contains a relatively large number of rare, localized, and endemic taxa (Feidler et at. 1998). The crinite mariposa lily is one such taxon. It occurs only within a narrow 30-mile (50-km) long band of serpentine soil that contains large amounts of iron and magnesium (Fredricks 1992). Even within this specific soil type, the crinite mariposa lily is not widely distributed as it primarily occupies the transition zone between coniferous forests and meadows.

Where is Cox's Mariposa Lily (Calochortus coxii) located in the wild?

Habitat:

Restricted to serpentine soils (Knight and Seevers 1992). Primarily found in the transition zone (ecotone) between coniferous forests and grass-shrub meadows, but also found in meadows (Fredricks 1993). Elevation 1400 to 2500 ft. (420-760 m) (Fredricks 1989).

Distribution:

Klamath Mountains of Oregon.

States & Provinces:

Cox's Mariposa Lily can historically be found in Oregon

Which CPC Partners conserve Cox's Mariposa Lily (Calochortus coxii)?

Rae Selling Berry Seed Bank & Plant Conservation Program

Conservation Actions

09/01/2020

Germination trials indicate that germination is stimulated by long periods (12-14 weeks) of cold, moist, dark stratification. This ensures that the seed will only germinate in the spring, when the seedlings chance for survival is greatest (Florance 1994). In germination studies at The Berry Botanic Garden, 100% germination was obtained after 8 weeks of cold stratification followed by a constant 68F (20C) environment. Between 80-100% of seeds germinated with 8 weeks of cold stratification and an alternating 50F/68F (10/20C) environment (BBG file). [Less...]

09/01/2020

09/01/2020

Seeds from three locations stored at The Berry Botanic Garden.

09/01/2020

Seeds from three locations stored at The Berry Botanic Garden.

Edward Guerrant, Ph.D.

08/30/2017

Collect and store seeds from known populations. Determine optimum propagation procedures and develop reintroduction protocols.

Edward Guerrant, Ph.D.

08/30/2017

Survey potential habitat for additional populations (Fredricks 1989). Determine the mechanism facilitating endemism to serpentine soils (Fredricks 1989). Soil and microsite analysis to identify critical factors to recruitment and success (Fredricks 1989). Continued monitoring (Fredricks 1992).

Edward Guerrant, Ph.D.

08/30/2017

In a three-year comparative demographic study of Calochortus coxii, permanent plots were monitored at two sites. Among C. coxii plants, bud production was highest and plants were most dense and larger on average in the ecotone (transition between coniferous forest and forb/grass meadow) habitat. Transition matrix models revealed that C. coxii was stable at one site, but clearly declining at another. Results were compared to a similar study with Calochortus umpquaensis (Fredricks 1993). Demographic comparisons using matrix model analysis of empirical data were made among eight Calochortus species. Results paint a mixed picture of population dynamics. For all species, population stage distribution (proportion of seedlings, juveniles, and reproductive adults) was highly variable between populations, habitats, and years. (Feidler et al. 1998). Germination trials indicate that germination is stimulated by long periods (12-14 weeks) of cold, moist, dark stratification. This ensures that the seed will only germinate in the spring, when the seedlings chance for survival is greatest (Florance 1994). In germination studies at The Berry Botanic Garden, 100% germination was obtained after 8 weeks of cold stratification followed by a constant 68F (20C) environment. Between 80-100% of seeds germinated with 8 weeks of cold stratification and an alternating 50F/68F (10/20C) environment (BBG file).

Edward Guerrant, Ph.D.

08/30/2017

Bulb collection and flower picking (Fredricks 1989). Grazing (Fredricks 1993). Seed predation (Fredricks 1993).

Nature Serve Biotics

05/02/2017

An Oregon endemic first discovered and described in 1988, this species is restricted to north-facing slopes on serpentine soils (FNA 2002). Its known distributional range is an area of less than 2600 hectares (in a province believed to be the center of speciation for a unique group of Calochortus). The species' habitat is heavily impacted by grazing, roads (Interstate 5 intersects a large population), and logging. Overgrazing, in particular, appears to have reduced the size of the population. Fire suppression is also causing habitats to shrink, and development from nearby towns is encroaching on habitats and making prescribed burning more difficult.

Edward Guerrant, Ph.D.

01/01/2010

There are 11 known sites, of which 8 are on Bureau of Land Management (BLM) land and 3 on private land. Population numbers as of 1992 and 1993 ranged from as little as two individuals to over 5,000, but most populations contained between 100 and 1000 individuals (ONHDB 2000).

Edward Guerrant, Ph.D.

01/01/2010

Seeds from three locations stored at The Berry Botanic Garden.