Physaria tuplashensis

Common Names:
White Bluffs bladderpod
Rollins, R.C., K.A. Beck, F.E. Caplow
Growth Habit:
CPC Number:
Profile Contributors:
Edward Guerrant, Ph.D.
Fully Sponsored

Reference Links

ITIS - Tropicos - USDA Plants - Fish & WildLife

Participating Institutions

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

The conservation of Physaria tuplashensis is fully sponsored.
Edward Guerrant, Ph.D. contributed to this Plant Profile.


In 1994, the Nature Conservancy of Washington and the US Department of Energy began the Hanford Biodiversity Project. The Hanford Nuclear Site, through which the Columbia River flows in south-central Washington, contains some of the largest remnant areas of ungrazed and undeveloped shrub steppe in the Pacific Northwest. The land had remained undisturbed as a security buffer zone around the nuclear reactor for at least 50 years. Intensive surveying and mapping was conducted to determine the plants and animals present on the site. Among the 30 different rare plant taxa found on the site, three were new to science, including Lesquerella tuplashensis, or White Bluffs bladderpod.

Was this new species a product of nuclear radiation A tongue-in-cheek article, suggesting that the new species found at Hanford were mutants, appeared in Outside Magazine shortly after the findings were announced. However, in this instance, we know that this species is not the result of a radiation-caused mutation. This plant was originally collected in the 1880's by one of the first natural history explorations in the Pacific Northwest. Botanists noticed that they were different from any known plants, but the specimens were not in good enough condition to lead to the conclusion that they were a different species. As a result of the work by the Hanford Biodiversity Project, the mystery was finally solved.

Lesquerella tuplashensis occupies a narrow ribbon of habitat that is only 5-40 ft (1.5-12 m) wide, and about 10 mi (17km) long, at the top edge of the dramatic White Bluffs above the Columbia River. Few other plants grow on the steep, almost vertical, habitat. The soil that it grows on is dry and highly alkaline (high pH) due to the high calcium content. The calcium in the soil causes the soil to be white. The name "tuplashensis" is derived from the Sahaptin language of the Wanapum tribe that occupied the White Bluffs area. "Plash" referred to the white color of the bluffs, and "Tuplash" was their name for the Bluffs (Rollins et al. 1995).

Distribution & Occurrence


Conservation, Ecology & Research