The following Participating Institutions are custodians for this species in the CPC National Collection:
Rae Selling Berry Seed Bank & Plant Conservation Programs
The conservation of Trifolium leibergii is fully sponsored.
Edward Guerrant, Ph.D. contributed to this Plant Profile.
In Oregon, Trifolium leibergii is restricted to an area that ranges 2 miles on either side of the Middle Fork of the Malheur River and continues for approximately 10 miles. Here, it grows on a distinct habitat characterized by a thin, gravelly soil layer consisting of decomposing (broken-down) volcanic ash "tuff." Underneath the thin layer of soil is the solid "tuff," which has deep cracks running through it. The taproot of Trifolium leibergii grows down into the cracks, causing neighboring plants to grow in a straight line (Nora Taylor, pers. comm.).
This attractive clover is easily recognized by its three hairy "oak-leaf" shaped leaflets. When the plant first emerges in early spring, the leaves are a beautiful, succulent green. As the plant ages, the leaves fade to gray (and sometimes purple!). The small flowers are clustered into large heads, which start a creamy white and fade to a pretty pink as they age. The plant produces tiny pods with one or two seeds each (Nora Taylor, pers. comm.).
Distribution & Occurrence
Trifolium leibergii grows on steep slopes comprised of dry, shallow soil derived from decomposing volcanic "tuff." Associated species are sparse, but most commonly include Artemisia arbuscula.
NV: Elko County
OR: Owyhee Uplands (Harney Co.)
|As of 2001: 26 sites in Oregon with a total of approximately 38,000 individuals. Most sites are on Federal (BLM) or State (Oregon Department of Fish and Wildlife) owned land. Approximately 10% of individuals are on private land. Surveys have not been exhaustive, so it is possible that more populations exist (Nora Taylor, pers. comm.)
7 occurrences in Nevada with a total of approximately 136,000 individuals (NNHP 2001).
Conservation, Ecology & Research
Because the plants emerge early in the spring and complete their life-cycle early, grazing is not a major threat. The habitat that Trifolium leibergii grows on supports little other vegetation and so is not a prime grazing area. Cattle may walk across the area, but they do not linger. There is some threat from trampling and habitat degradation due to the creation of livestock trails (Nora Taylor, pers. comm.).
Little is known about the specific ecology of this species. It is believed to be pollinated by a small native bee (Nora Taylor, pers. comm.).
Cattle trails through habitat (Nora Taylor, pers. comm.)
Possible threats to native pollinators.
Germination trials at The Berry Botanic Garden. Seeds were either cold stratified for 8 weeks or not cold stratified. They were then placed in either constant 68F (20C) or alternating 50/68F (10/20C) temperature chambers. All treatments resulted in 100% germination (BBG File).
No monitoring on BLM land in Oregon as of 2001. A plan is being developed to begin monitoring populations in 2002 or 2003 (Nora Taylor, pers. comm.).
Sites on BLM land in Oregon are on grazing allotments, but cattle do not linger in the area (Nora Taylor, pers. comm.)
Seeds from 5 sites stored at The Berry Botanic Garden (BBG File).
Study general ecology of the species.
Determine propagation and re-introduction protocols.