Pinguicula vulgaris L.

Pinguicula vulgaris
Troy Weldy

Dicotyledoneae (Dicots)
Lentibulariaceae (Bladderwort Family)
State Protection
Listed as Endangered by New York State: in imminent danger of extirpation in New York. For animals, taking, importation, transportation, or possession is prohibited, except under license or permit. For plants, removal or damage without the consent of the landowner is prohibited.
Federal Protection
Not Listed
State Conservation Status Rank
Critically Imperiled or Imperiled in New York - Especially or very vulnerable to disappearing from New York due to rarity or other factors; typically 20 or fewer populations or locations in New York, very few individuals, very restricted range, few remaining acres (or miles of stream), and/or steep declines. More information is needed to assign either S1 or S2.
Global Conservation Status Rank
Secure globally - Common in the world; widespread and abundant (but may be rare in some parts of its range).


Did you know?

Butterwort is New York's only insectivorous plant which is not found in a marsh, bog, or swamp. Sometimes its pollinators are also unlucky enough to be caught and absorbed by the leaves. The name butterwort comes from its old world reputation of having medicinal and culinary uses. The juices from the leaves were rubbed onto cows' udders to protect them from infection. Another reference to butter was the use of its leaves to curdle milk. The genus name Pinguicula can be translated as little fat one or fattish for the greasy texture of the leaves.

State Ranking Justification

There are six known populations and approximately six additional historical populations of this plant. Most of these populations are on well-protected cliffs, but some cliffs may be subject to natural or artificial sloughing. This plant has a limited range, and an even greater limited habitat. As a plant at the southern limit of its range, it has always likely been rare in New York.

Short-term Trends

The short-term trend of this plant seems to be stable. This plant is difficult to survey and population counts from year-to-year are usually not recorded. Changes would be noted only if the area where the plants occur was drastically altered but this has not occurred in the recent past.

Long-term Trends

Over half of the seven historical sites for this plant have been rediscovered and no sites have been considered extirpated. The habitat for this plant is not common but it is isolated and inaccessible enough that the plants are expected to remain here for many decades.

Conservation and Management


There are few threats to these plants since the sites are inaccessible and not open to disturbance. Changes in the amount of groundwater available to the sites could affect them in the future. So far no exotic invasive plants have been seen affecting these sites.

Conservation Strategies and Management Practices

Sites should be monitored for changes in groundwater availability and for any new invasive plants that might be affecting them.

Research Needs

There are no research needs to report at this time.



A plant of seepage areas on open limey-shale cliffs or in the mist of a nearby waterfall. These sites have been lumped under the cliff community designation, but they may be best described as vertical marly fens. The sites are usually surrounded by birch, hemlock, and maple. (New York Natural Heritage Program 2005). A distinct calciphile, growing on alkaline rocks and sands (as on interdunal flats and hollows), marly flats, and occasionally in marly fens and on moist rock outcrops; frequently growing with Primula mistassinica (Voss 1996). Wet rocks and shores, occasionally in bogs and wet meadows inland. (Gleason and Cronquist 1991). Wet rocks and open spots, chiefly in calcareous areas (Fernald 1970).

Associated Ecological Communities

  • Calcareous cliff community* (guide)
    A community that occurs on vertical exposures of resistant, calcareous bedrock (such as limestone or dolomite) or consolidated material; these cliffs often include ledges and small areas of talus.
  • Cliff community (guide)
    A community that occurs on vertical exposures of resistant, non-calcareous bedrock (such as quartzite, sandstone, or schist) or consolidated material; these cliffs often include ledges and small areas of talus.
  • Shale cliff and talus community (guide)
    A community that occurs on nearly vertical exposures of shale bedrock and includes ledges and small areas of talus. Talus areas are composed of small fragments that are unstable and steeply sloping; the unstable nature of the shale results in uneven slopes and many rock crevices.

* probable association but not confirmed.

Associated Species

  • Aquilegia canadensis (wild columbine, red columbine)
  • Carex flava (yellow sedge)
  • Conocephalum conicum
  • Cystopteris bulbifera (bulblet fern)
  • Eupatorium rugosum
  • Impatiens capensis (spotted jewelweed, spotted touch-me-not)
  • Lobelia kalmii (Kalm's lobelia)
  • Parnassia glauca (common grass-of-Parnassus)
  • Primula mistassinica (Lake Mistassini primrose, bird's-eye primrose)
  • Saxifraga aizoides (yellow mountain saxifrage)
  • Saxifraga virginiensis
  • Solidago ohioensis (Ohio flat-topped-goldenrod)
  • Tussilago farfara (colts-foot)


New York State Distribution

This plant is restricted to central and western New York, associated with the spray zone of waterfalls and within seepage areas of cliffs made up of fossilliferous shale. New York is at the southern limit of its range.

Global Distribution

In North America, this circumboreal species ranges from Labrador to Alaska, south to northern New England, New York, Michigan, Minnesota, and Oregon.

Identification Comments

General Description

Butterwort is a small insectivorous plant. It has a small basal rosette of bright green to yellow-green, narrow tongue-shaped leaves that are covered with sticky glands that give it a shiny, waxy appearance. The margins of the leaves curl inward as insects are trapped and digested. One to nine flower stalks grow up to 6 inches high from the basal rosette and are topped by a single, tubular, violet flower. The flower has 5 petals in two lips and they are white and hairy at the base. The bottom of the flower ends in a long spur. In the winter the leaves die back to form a bulblike winter bud or hibernacula that has smaller daughter buds that ring the main winter bud. These then germinate in the spring to grow more plants.

Identifying Characteristics

This insectiverous plant has leaves that are spatulate to elliptical, 2-6 cm long, and yellowish-green that are covered with a sticky slime. These leaves will promptly curl when picked. The scape is 0.4-1.5 cm high. The corolla, excluding the straight spur, is 1-2 cm long and violet. Its lips are very unequal and its tube funnelform. Small insects caught on the slimy leaf surfaces are digested.

Best Life Stage for Proper Identification

This plant is easiest to identify in flower, but may also be identified vegetatively. To verify the identification, a few good pictures and a description of the habitat should suffice.

Similar Species

The combination of habitat and morphology make this plant rather unique, particularly when in flower. Vegetative leaves of Lobelia kalmii and other plants with basal rosettes may look somewhat similar to those unfamilar with these species. The slimy leaf surface of Pinguicula is unique.

Best Time to See

This cliff species flowers from late May to early July, with fruits persisting through the end of summer. Since this plant can be identified vegetatively, surveys can be conducted at any point during the growing season.

  • Vegetative
  • Flowering
  • Fruiting

The time of year you would expect to find Butterwort vegetative, flowering, and fruiting in New York.

Butterwort Images


Pinguicula vulgaris L.

  • Kingdom Plantae
    • Phylum Anthophyta
      • Class Dicotyledoneae (Dicots)
        • Order Scrophulariales
          • Family Lentibulariaceae (Bladderwort Family)

Additional Common Names

  • Bog-violet


  • Pinguicula vulgaris var. americana Gray [If the Eurasian and North American taxa are separate, ours would likely be listed as this variety.]

Additional Resources

Best Identification Reference

Gleason, Henry A. and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York. 910 pp.

Other References

Fernald, M.L. 1950. Gray's manual of botany. 8th edition. D. Van Nostrand, New York. 1632 pp.

Holmgren, Noel. 1998. The Illustrated Companion to Gleason and Cronquist's Manual. Illustrations of the Vascular Plants of Northeastern United States and Adjacent Canada. The New York Botanical Garden, Bronx, New York.

Mitchell, Richard S. and Gordon C. Tucker. 1997. Revised Checklist of New York State Plants. Contributions to a Flora of New York State. Checklist IV. Bulletin No. 490. New York State Museum. Albany, NY. 400 pp.

New York Natural Heritage Program. 2010. Biotics database. New York Natural Heritage Program. New York State Department of Environmental Conservation. Albany, NY.

New York Natural Heritage Program. 2024. New York Natural Heritage Program Databases. Albany, NY.

Schnell, Donald E. 2002. Carnivorous Plants of the United States and Canada. Second edition. Timber Press, Portland, Oregon.

Voss, Edward G. 1996. Michigan Flora Part III. Dicots Concluded (Pyrolaceae - Compositae). Cranbrook Institute of Science Bulletin 61 and University of Michigan Herbarium. 622 pp.

Weldy, T. and D. Werier. 2010. New York flora atlas. [S.M. Landry, K.N. Campbell, and L.D. Mabe (original application development), Florida Center for Community Design and Research http://www.fccdr.usf.edu/. University of South Florida http://www.usf.edu/]. New York Flora Association http://newyork.plantatlas.usf.edu/, Albany, New York


About This Guide

Information for this guide was last updated on: March 18, 2005

Please cite this page as:
New York Natural Heritage Program. 2024. Online Conservation Guide for Pinguicula vulgaris. Available from: https://guides.nynhp.org/butterwort/. Accessed July 19, 2024.