Sidalcea oregana var. calva
|Oregon checker-mallow, Wenatchee checker-mallow|
|Edward Guerrant, Ph.D.|
The following Participating Institutions are custodians for this species in the CPC National Collection:
Rae Selling Berry Seed Bank & Plant Conservation Programs
University Of Washington Botanic Gardens
Cincinnati Zoo & Botanical Garden
The conservation of Sidalcea oregana var. calva is fully sponsored.
Edward Guerrant, Ph.D. contributed to this Plant Profile.
In September of 2001, the U.S. Fish and Wildlife Service caught the attention of many botanists with a promising news release. They had officially designated 6,135 acres of seasonal wetlands as "critical habitat" for the endemic Wenatchee Mountains checker-mallow. The U.S. Fish and Wildlife Service listed Sidalcea oregana var. calva as Endangered in 1999, legally protecting individual plants on Federal land from activities that could cause their destruction. The critical habitat designation is also important because it protects most of the approximately 125 acres of habitat that this rare plant currently inhabits and it protects significant additional habitat to allow for population expansion and overall health of the ecosystem. By establishing conservation of this delicate habitat, activities on Federal land that will disturb the habitat, such as up-slope disturbances from road construction, logging or other hydrological alterations will be precluded.
Sidalcea oregana var. calva is found growing with another rare species, Delphinium viridescens (Wenatchee larkspur) at three sites (this species is also profiled on this web site). They share similar habitat requirements, so it stands to reason that conservation efforts to protect habitat for one species will benefit the other.
Distribution & Occurrence
Sidalcea oregana var. calva is found most often in moist meadows with surface water or saturated soil from spring into early summer. Occasionally, it is found in open conifer stands dominated by Douglas-fir (Pseudotsuga menziesii) and Ponderosa pine (Pinus ponderosa) or on the margins of shrubs and hardwood thickets. Approximate elevation ranges from 1,970 to 3,300 ft (600-1000 m).
|As of 2001: Six populations with approximately 3,600 individuals total over a total area of approximately 125 acres. Three populations are very small. Approximate population sizes are as follows: 2 populations have 5 or fewer individuals, one has approximately 30, the other populations are larger (100 individuals or more) with the largest having as many as 2500 individuals. Most plants are located on land designated as a Natural Area Preserve managed by the Washington Department of Natural Resources. Others are found on U.S. Forest Service land and areas of private property (USFWS 2001).|
Conservation, Ecology & Research
Flowering begins in mid- to late June and usually peaks in mid- to late July, but may continue into mid-August. Fruits usually develop by early August (WNHP 1999). Little is known about the specific ecology of this species. Studies on the pollinators and reproductive ecology are currently underway.
The species commonly found growing near S. oregana var. calva include: quaking aspen (Populus tremuloides), black hawthorn (Crataegus douglasii), snowberry (Symphoricarpos albus), serviceberry (Amelanchier alnifolia), few-flowered peavine (Lathyrus pauciflorus), sticky purple geranium (Geranium viscosissimum) and California false helleborne (Veratrum californicum) (USFWS 1999).
Seed herbivory by weevils.
Because of the low population numbers, populations are susceptible to extirpation due to random events.
Conversion of habitat to housing, agricultur
-Pollination studies are being conducted to determine whether increased pollination (hand pollination) increases fruit/seed development, possibly indicating a pollination limitation. Pollinators are being observed and identified (Goldsmith 2001).
-The effect of controlled burning after plants have released mature seed is being investigated. Small plots (2m x 2m) containing Sidalcea oregana var. calva were burned in October of 2001 and will be compared to control plots (unburned) the following growing season. The hypothesis is that S. oregana var. calva will re-sprout after fire with increased vigor (Goldsmith 2001).
-Observational studies are being conducted on seed predation by weevils. Weevils have been noted in fruits and flowers in many S. oregana var. calva studies and recent observations have shown that they destroy seeds in alarming proportions of fruits (Goldsmith 2001).
Germination studies at The Berry Botanic Garden have yielded no germination. Seeds were subjected to 8 weeks of cold stratification or no cold stratification which was followed by either constant 68F (20C) or alternating 50F/68F (10C/20C) temperatures. It is not known whether the conditions for germination were not met or if seed was not viable (BBG File).
Listed as Endangered by the State of Washington and the U.S. Fish and Wildlife Service.
"Critical Habitat" for Sidalcea oregana var. calva designated in 2001.
A Recovery Plan is being developed. The draft is expected to be completed early in 2002.
Continue studying the effect of burning on Sidalcea oregana var. calva, including the effects of fire on seed viability and germination (Goldsmith 2001).
Investigate the effects of burning on weevils, including how time of burn may be important (e.g. if it is best to burn Sidalcea oregana var. calva in the fall, but the weevils have completed their lifecycle and can fly by then, the burn may not have the desired effect of destroying the weevils) (Goldsmith 2001).
Conduct a controlled (greenhouse) study of the reproductive mechanism of Sidalcea oregana var. calva, which may aid future conservation efforts (Goldsmith 2001).
Determine germination requirements.
Determine propagation and reintroduction protocols.
Scoggan, H.J. 1978. The Flora of Canada. National Museums of CA, Publications in Botany.