Truckee Barberry

Berberis sonnei

Description

Truckee barberry, Berberis sonnei, is one of only two shrubs in the otherwise herbaceous barberry family. Also known as the Truckee berberis, this shrub grows from 8-20 in (20-50 cm) tall and bears compound pinnate leaves that are lustrous green on the upper surface with bristle-tipped teeth on the margin. Yellow flowers bloom from mid-April to late May and emit a carnation-like aroma. Fruits mature and turn a dark blue or purple by late September and contain numerous shiny, light brown seeds.

In spite of the profusion of seeds, most plants reproduce vegetatively from underground shoots.In early May, new shoots push out of the ground up to 3 ft (1 m) from the nearest parent plant. Simultaneously, an abundance of new leaves appear on old growth. Barberries in the wild are considered evergreen, yet for some unknown reason, cultivated plants lose most of their leaves over winter.

Questions have raised by botanists whether B. sonnei is distinct from the barberry species Berberis repens. If scientists conclude that Truckee barberry is not a valid taxon, it may result in the delisting of the species. The species has also been described as Mahonia sonnei.

Habitat

Surviving plants of the only known population grow along a river bank lined with large granite boulders. Soil is a sandy, silt-loam underlain by gravel. The site is about 6-10 ft (2-3 m) above the summer water level of the river and barely above the level of spring floods.

The habitat elevation is about 5,940 ft (1,800 m) in an exceptionally cold area of California about 10 mi (16 km) east of Donner Pass at the lower end of the valley containing Donner Lake. Cold air flowing down the canyon keeps the temperature low year-round. The average yearly minimum is 21°F (-6°C), and winter lows can plunge below zero.

Distribution

The Truckee barberry is probably endemic to the Truckee River Valley and was once more abundant along that river.

For almost 70 years after Truckee barberry was initially described and classified, it was lost and thought extinct. Unsuccessful searches were made for the plant in the 1930s and 1940s. Before the search was renewed by state botanists in 1973, an illustration of the plant was featured in a local newspaper. A high school student recognized the plant from the picture and led searchers to what is now the only known wild population. This population, on the banks of the Truckee River near the town of Truckee, consists of two colonies. In 1985, one colony contained fewer than ten small plants, the other about 40.

Threats

Truckee barberry has survived considerable stress since the settlement of the area. Early Truckee was a lumbering center, and the area was denuded to furnish timbers for Nevada mines, for railroad ties, and for bridge supports for the transcontinental railroad. Check dams were built on the river to flush logs downstream, which stripped the river banks of much of its natural vegetation, including presumably, the barberry.

The most immediate threats to the plant are its low numbers, restricted distribution, and the difficulty of managing the site, which is privately owned in a populated area. In 1982, one of the two colonies was cut back to the rock wall from which it emerges. It resprouted vigorously, however. Other plants are crowding the current colonies and should be removed.

Conservation and Recovery

Botanists have succeeded in establishing a small, expanding colony of healthy plants that will be used to repopulate known historic sites. An attempt to germinate a very limited number of wild-collected seeds was unsuccessful.

Truckee barberry's hold on survival will remain tenuous until some form of permanent protection is achieved. The California Department of Fish and Game is expected to take the lead on the recovery effort.

Contact

U.S. Fish and Wildlife Service
Division of Endangered Species
Eastside Federal Complex
911 N.E. 11th Avenue
Portland, Oregon 97232
http://pacific.fws.gov/

References

Abrams, L. R. 1934. "The Berberises of the PacificStates." Phytologia 1:89-94.

Roof, J. B. 1974. "Found Alive: The Truckee Bar-berry." Four Seasons 4(4):1-18.

U.S. Fish and Wildlife Service. 1984. "Recovery Plan for Truckee Barberry." U.S. Fish and Wildlife Service, Portland.