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BC Conservation Data Centre: Species Summary


Antennaria flagellaris
stoloniferous pussytoes

 
Scientific Name: Antennaria flagellaris (A. Gray) A. Gray
English Name: stoloniferous pussytoes
 
Classification / Taxonomy
Scientific Name - Concept Reference: Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Classification Level: Species
Species Group: Vascular Plant
Species Code: ANTEFLA
Kingdom Phylum Class Order Family
Plantae Anthophyta Dicotyledoneae Asterales Asteraceae
   
Conservation Status / Legal Designation
Global Status: G5 (Aug 2014)
Provincial Status: S2 (Apr 2019)
BC List: Red
Provincial FRPA list:   
Provincial Wildlife Act:
COSEWIC Status: Endangered (May 2004)
SARA Schedule: 1  -  Endangered (Jul 2005)
General Status Canada: 1 - At Risk (2010)
   
Ecology & Life History
General Description:
Technical Description:
Subspecies Comments: No subspecies are known to occur in B.C.
Identification Comments: Antennaria flagellaris is easily distinguished from other Antennaria species in B.C. by its conspicuous slender, leafless stolons (Douglas et al. 1998b). Cronquist (1955) describes A. flagellaris as "an unmistakable species". The species is easily overlooked, however, due to its small size and inconspicuous colour.
Similar Species: No known look-alikes in B.C.
Provincial Reproduction Comments: The genus Antennaria is dioecious with female and male flower heads borne on different plants. While some Antennaria species reproduce by apomixis (setting seed without fertilization), A. flagellaris produces seeds sexually by outcrossing (Bayer 1996). Pollen is transferred by wind from male to female plants. The fruit is an achene, which contains a single seed. The numerous hair-like bristles of the mature achene facilitate its dispersal by wind. A. flagellaris also reproduces vegetatively by producing stolons that terminate in plantlets. Initially, the mother plant provides the plantlet with nutrients via the stolon. The genetically identical plantlets eventually become independent plants as stolons are severed. This mode of reproduction results in very restricted dispersal, as stolons only grow up to 10 cm long (Douglas et al. 1998b).
Provincial Ecology Comments: Antennaria flagellaris experiences relatively little competition in the sparsely vegetated sites it occupies in B.C. (Douglas et al. 2004).
Habitats:
(Type / Subtype / Dependence) 		Other Unique Habitats / Vernal Pools/Seasonal Seeps / Facultative - frequent use
Rock/Sparsely Vegetated Rock / Rock/Sparsely Vegetated Rock / Facultative - frequent use
Global Habitat Comments: Rocky areas within sage scrub.
Provincial Habitat Comments: B.C. occurrences of Antennaria flagellaris are located within the Okanagan Very Dry Hot Interior Douglas-fir (IDFxh1) biogeoclimatic unit (Lloyd et al. 1990). Climatic conditions in the IDFxh1 are continental, characterized by hot, dry summers, a fairly long growing season, and cool winters. Antennaria flagellaris populations occur in a matrix of level to gently sloping Artemisia tridentata shrub/grasslands with scattered Pinus ponderosa and Pseudotsuga menziesii at the western edge of the distribution of open shrub/grasslands. The A. flagellaris sites occur on moderate slopes with southerly aspects. These sites have a unique hydrology characterized by ephemeral winter seepage followed by drying in early summer. This results in an eroded, unstable slope due to slow downslope soil movement. As a result, the sites are sparsely vegetated. The unusual soil moisture regimes of the sites may be due to bentonite outcroppings or other soil characteristics (Douglas et al. 2004).
Provincial Phenology:
(1st half of month/
2nd half of month)		 Mar: / Vegetative
May: Flowering /
Jun: Flowering /
Provincial Phenology Comments: In B.C., Antennaria flagellaris flowers in May and June. The exact phenology of the germination, vegetative, and fruiting stages is unknown.
Elevation (m) (min / max): Provincial:  910 / 970
Known Pests:
Pollen Vector:
Pollinator:
Dispersal:
   
 
Provincial Inventory
Inventory Priority: B - Strong
Ownership of occurrences (Known locations): Mostly private
Inventory Need: Monitoring of all sites containing Antennaria flagellaris is recommended since fluctuations in population size can occur annually, which makes it difficult to assess population trends. Habitat mapping is needed to identify areas of good potential habitat that have not yet been surveyed. Inventories should be conducted by a qualified botanist at the appropriate time of year.
Inventory Comments: A national survey for Antennaria flagellaris was carried out 2002 for the last COSEWIC status report (Douglas et al. 2004). In 2002 and 2003, Frank Lomer was also contracted to search for new sites in the Princeton area. He surveyed the east side of the Similkameen River opposite the known sites and along the U.S. border near Grand Forks, Anarchist Mountain, and Midway but did not find any new sites (Douglas and Penny 2003b).
 
Economic Attributes
Provincial Economic Comments: Antennaria flagellaris has no known economic attributes in B.C.
 
Distribution
Endemic: N
Global Range Comment: Ranges from British Columbia south to California, Nevada, and east to Idaho, with disjunct populations in northwest Wyoming.
Disjunct, more common elsewhere: N
Peripheral, major distribution elsewhere: Y
 
Authors / Contributors
Global Information Author:
Last Updated:
Provincial Information Author: Barton, K.
Last Updated: Mar 24, 2005
Last Literature Search:
   
References and Related Literature
B.C. Ministry of Environment. Recovery Planning in BC. B.C. Minist. Environ. Victoria, BC.
COSEWIC. 2004i. COSEWIC assessment and status report on the stoloniferous pussytoes Antennaria flagellaris in Canada. Comm. on the Status of Endangered Wildl. in Can. Ottawa. vii+ 18 pp..
Cronquist, A. 1955. Compositae. In C.L. Hitchcock, A. Cronquist, M. Ownbey, and J.W. Thompson (eds.). Vascular plants of the Pacific Northwest. Part 5. Univ. Washington Press, Seattle. 343 pp.
Douglas, G.W., D. Meidinger, and J. Penny. 2002. Rare Native Vascular Plants of British Columbia, 2nd ed. B.C. Conserv. Data Centre, Terrestrial Inf. Branch, Victoria. 358pp.
Douglas, G.W., F. Lomer, and H. Roemer. 1998. New or Rediscovered Native Vascular Plant Species in British Columbia. Can. Field-Nat. 112(2):276-279.
Douglas, G.W., G.D. Straley, and D. Meidinger, eds. 1998b. Illustrated Flora of British Columbia, Vol. 1, Gymnosperms and Dicotyledons (Aceraceae through Asteraceae). B.C. Minist. Environ., Lands and Parks, Wildl. Branch, and B.C. Minist. For. Res. Program. 436pp.
Douglas, G.W., J.L. Penny, and K. Barton. 2003. Status of Stoloniferous Pussytoes (Antennaria flagellaris) in British Columbia. B.C. Minist. Water, Land and Air Protection, Biodiversity Branch, and B.C. Minist. Sustainable Resour. Manage., Conservation Data Centre, Victoria, BC. Wildl. Bull. B-107. 14pp.
Douglas, G.W., J.L. Penny, and K. Barton. 2003a. Status Report on Stoloniferous Pussytoes, Antennaria flagellaris, in Canada. Unpubl. rep. submitted to the Comm. on the Status of Endangered Wildl. in Can. Ottawa. 19pp.
Southern Interior Rare Plants Recovery Implementation Group. 2008b. Multi-species recovery strategy for the Princeton Landscape, including dwarf woolly-heads (Psilocarphus brevissimus var. brevissimus), slender collomia (Collomia tenella), and stoloniferous pussytoes (Antennaria flagellaris) in British Columbia. Prepared for the B.C. Ministry of Environment, Victoria, BC. 28 pp.
 

Please visit the website Conservation Status Ranks for definitions of the data fields used in this summary report.

Suggested Citation:

B.C. Conservation Data Centre. Species Summary: Antennaria flagellaris. B.C. Minist. of Environment. Available: https://a100.gov.bc.ca/pub/eswp/ (accessed Jun 13, 2026).