National Collection of Imperiled Plants

CPC National Collection Plant Profile

Photographer:

Ed Florance

Search Alphabetical List Reference Finder CPC Home

CPC National Collection Plant Profile

Trifolium leibergii

Family:	Fabaceae
Common Name:	Leiberg's clover
Author:	A. Nels. & J.F. Macbr.
Growth Habit:	Forb/herb
CPC Number:	4325

Distribution
Protection
Conservation
References

Profile Links

ITIS
Tropicos
PLANTS
Fish & WildLife

enlarge

Photographer: Ed Florance

Trifolium leibergii is Not Sponsored

Primary custodian for this plant in the CPC National Collection of Endangered Plants is:

Rae Selling Berry Seed Bank & Plant Conservation Program

Edward Guerrant, Ph.D. contributed to this Plant Profile.

Trifolium leibergii

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

Top

State Range

Nevada
Oregon

Habitat

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.

Distribution

OR, NV
NV: Elko County
OR: Owyhee Uplands (Harney Co.)

Number Left

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).

Protection

Top

Global Rank:	G2	7/9/2007	Guide to Global Ranks
Federal Status:	SC		Guide to Federal Status
Recovery Plan:	No

State/Area Protection

State/Area	Rank	Status	Date
Nevada	S2	WATCH	3/30/2001
Oregon	S1	CAND	2/1/2001

Conservation, Ecology & Research

Top

Ecological Relationships

Trifolium leibergii begins its growing season fairly early in the spring. If conditions are dry, plants may remain dormant and emerge in subsequent years when conditions are more favorable. Because plants may not emerge in dry years, the task of monitoring populations and tracking population numbers may be difficult. Also, plants may grow close to each other as they grow from the cracks in the "tuff." This makes it difficult to distinguish individuals and to get an accurate count of individuals. From observation however, it appears that populations are relatively stable. New locations are being discovered as the area is searched, so it is possible that many more populations exist (Nora Taylor, pers. comm.).

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.).

Threats

� ORV use (Nora Taylor, pers. comm.)
� Cattle trails through habitat (Nora Taylor, pers. comm.)
� Possible threats to native pollinators.

Current Research Summary

� Germination trials at Lewis and Clark College. Seeds germinated readily in both 41�F (5�C) conditions and 68�F (20�C) conditions (Florance 1994).
� 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 68�F (20�C) or alternating 50�/68�F (10�/20�C) temperature chambers. All treatments resulted in 100% germination (BBG File).

Current Management Summary

� Recent searches in Oregon have revealed numerous new occurrences (Nora Taylor, pers. comm.).
� 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).

Research Management Needs

� Monitor sites to determine population trends.
� Study general ecology of the species.

Ex Situ Needs

� Collect and store seed from populations across range.
� Determine propagation and re-introduction protocols.

References

Top

Books (Single Authors)

ONHP. 2001. Rare, Threatened and Endangered Plants and Animals of Oregon.

Electronic Sources

NNHP. (2001). Detailed Rare Plant and Lichen Lists. Nevada Natural Heritage Program. http://www.state.nv.us/nvnhp/selists.htm. Accessed: 2002.

ONHDB. (2000). Oregon Natural Heritage Program Database. Portland, Oregon.

Journal Articles

1918. (Original Publication). Botanical Gazette. 65, 1: 58-59.

Personal Communications

Taylor, N. 2001. Personal communication. Nora Taylor. Botanist, Bureau of Land Management, Burns District, Hines, Oregon.

Reports

Florance, E.R. 1994. Germination, Dormancy, and Structure of Seeds From Rare and Endangered Plant Species in Oregon. Unpublished Final Report. Cooperative Challenge Cost-Share Project funded by Bureau of Land Management and Lewis and Clark College.

NNHP. 2001. Nevada Rare Plant Atlas: Index to Maps and Fact Sheets. Portland, Oregon and Reno, Nevada: Carson City: Nevada Natural Heritage Program, compiled for the U.S. Department of the Interior, Fish and Wildlife Service. Grant EP-3-12.

Search Other National Collection Profiles

This profile was updated on 3/8/2011