Divide Bladderpod - Physaria klausii
State Rank Reason (see State Rank above)
State endemic restricted to central-Montana with the majority of populations occurring in the Big Belt Mountains and extending north to the southern end of the Rocky Mountain Front. Many large populations exist and the species typically occurs on gravelly slopes that are not usually subject to human disturbance.
- Details on Status Ranking and Review
Score1 - Moderate: Generally 10,000-100,000 individuals.
Score3 - Local Endemic or Very Small Montana Range: Generally restricted to an area <10,000 sq. miles (equivalent to the combined area of Phillips and Valley Counties) or <6 Sub-basins (4th code watersheds) Range-wide OR limited to one Sub-basin in Montana
Area of Occupancy
Score1 - Moderate: Generally occurring in 11-25 Subwatersheds (6th Code HUC’s).
Score1 - Moderate: Species is restricted to a specific habitat that is more widely distributed or to several restricted habitats and is typically dependent upon relatively unaltered, good-quality habitat (C Values of 5-7).
ScoreNA - Rank factor not assessed.
CommentTrends unknown though populations are likely stable or experiencing only minor declines.
Score0-1 - Low to Medium.
Score0-1 - Low to Moderate Vulnerability.
Raw Conservation Status Score
6 to 8 total points scored out of a possible 16 (Rarity factors and threats only).
Stems ascending, 4–20 cm from a simple caudex. Basal leaves rosulate, 1–4 cm long, the blade obovate to orbicular, entire or few-toothed. Stem leaves oblanceolate, entire or few-toothed. Vestiture of loosely spreading stellate hairs. Petals 6–8 mm long. Fruit obovate, slightly bilobed above, wider than high, 2–4 mm high, flattened perpendicular to the septum; style 2–3 mm long; seeds 2 per locule; pedicels sigmoid, 3–10 mm long (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX
Flowering in May and June with fruiting usually beginning as early as late May and continuing into July.
Physaria geyeri closely resembles Physaria klausii and a technical manual should be consulted to distinguish between the two. The two species are usually separable by the smaller fruits of P. klausii and the mostly disjuct ranges of the two; with P. geyeri occurring to the south of P. klausii.
Montana endemic, restricted to Broadwater, Lewis and Clark, and Meagher Counties.
Observations in Montana Natural Heritage Program Database
Number of Observations:
(Click on the following maps and charts to see full sized version)
Map Help and Descriptions
(Observations spanning multiple months or years are excluded from time charts)
Open shale slopes and gravelly areas, typically in bunchgrass communities in the montane to subalpine zone.
Ecological Systems Associated with this Species
- Commonly Associated with these Ecological Systems
Most species of Physaria are cross-pollinated by insects. Seed dispersal is probably most prevalent near the parent plant, though longer dispersal by wind and gravity are possible. High recruitment levels the two years following a wildfire have been noted. Reproduction by seed is the only means of recruitment. Individual populations vary in size from a few plants to several thousand plants. P. klausii appears tolerant of light to moderate disturbance based on the unstable habitats it frequently occupies.
Threats or Limiting Factors
STATE THREAT SCORE REASON
Reported threats to Montana's populations of Divide Bladderpod are primarily due to noxious weeds and livestock grazing and trampling (MTNHP Threat Assessment 2021). Noxious weeds are found at many populations. While many populations occur on rocky, steep terrain; some are accessible to livestock where disturbance from trampling is likely to benefit the spread of noxious species. One population is located where herbicide application is expected to have minor impacts. Another population was likely lost to conifer encroachment. Information about the likelihood for conifer encroachment to threaten Divide Bladderpod populations in the future is needed.
- Literature Cited AboveLegend: View Online Publication
- Lesica, P., M.T. Lavin, and P.F. Stickney. 2012. Manual of Montana Vascular Plants. Fort Worth, TX: BRIT Press. viii + 771 p.
- Additional ReferencesLegend: View Online Publication
Do you know of a citation we're missing?
- Al-Shehbaz, I. A. and S. L. O'Kane. 2002. Lesquerella is united with Physaria (Brassicaceae). Novon 12:319-329.
- Heidel, B.L. and S.V. Cooper. 1998. Botanical survey of the Scratchgravel Hills, Lewis & Clark County, Montana. Unpublished report to the Bureau of Land Management. Montana Natural Heritage Program, Helena, Montana. 44 pp. + appendices.
- Mincemoyer, S. 2005. Surveys of significant plant resources and related vegetation types for the Butte Office of the Bureau of Land Management. Montana Natural Heritage Program, Helena, MT. 11 pp + appendices.
- Poole, J.M. and B.L. Heidel. 1993. Sensitive plant surveys in the Big Belt and Elkhorn Mountains, Helena National Forest, Montana. Unpublished report to the Helena National Forest. Montana Natural Heritage Program. Helena, MT. 129 pp. plus printouts, maps.
- Rollins, R. C. 1984. Studies in the Cruciferae of western North America II. Contributions Gray Herbarium 214:1-18.
- Rollins, R. C. 1993. The Cruciferae of Continental North America: systematics of the mustard family from the Arctic to Panama. Stanford University Press, Stanford, California. 976 pp.
- Shelly, J.S. 1988. Status review of Lesquerella klausii, U.S. Forest Service, Region 1, Helena and Lewis & Clark National Forests. Unpublished report to U.S. Forest Service, Region 1, Missoula. Montana Natural Heritage Program, Helena, MT 82 pp.