Plants and Animals

Vaccinium cespitosum Dwarf bilberry

species photo
Susan R. Crispin
species photo
William W. Brodovich

Key Characteristics

Very low prostrate shrub of open habitat in the Upper Peninsula; forming circular clones in dense mats up to several meters in diameter; small, roundish deciduous leaves have bristle-tipped teeth; single, pinkish, bell-shaped flowers are borne in the leaf axils.

Status and Rank

US Status:
State Status: T - Threatened (legally protected)
Global Rank: G5 - Secure
State Rank: S1S2 - Rank is uncertain, ranging from critically imperiled to imperiled

Occurrences

CountyNumber of OccurrencesYear Last Observed
Alger42017
Keweenaw21986
Marquette32005
Ontonagon32007
Schoolcraft22017

Information is summarized from MNFI's database of rare species and community occurrences. Data may not reflect true distribution since much of the state has not been thoroughly surveyed.

Habitat

Dwarf bilberry occurs in open or semi-open habitats in the Upper Peninsula on dry, sandy soil. It is also found in seasonally wet, meadow-like areas intermixed with dry northern forest and dry sand prairie.

For each species, lists of natural communities were derived from review of the nearly 6,500 element occurrences in the MNFI database, in addition to herbarium label data for some taxa. In most cases, at least one specimen record exists for each listed natural community. For certain taxa, especially poorly collected or extirpated species of prairie and savanna habitats, natural community lists were derived from inferences from collection sites and habitat preferences in immediately adjacent states (particularly Indiana and Illinois). Natural communities are not listed for those species documented only from altered or ruderal habitats in Michigan, especially for taxa that occur in a variety of habitats outside of the state.

Natural communities are not listed in order of frequency of occurrence, but are rather derived from the full set of natural communities, organized by Ecological Group. In many cases, the general habitat descriptions should provide greater clarity and direction to the surveyor. In future versions of the Rare Species Explorer, we hope to incorporate natural community fidelity ranks for each taxon.

Associated Plants

Big bluestem, little bluestem, Pennsylvania sedge, tower mustard, whorled milkweed, Ohio horse mint, old field balsam, hairy hawkweed, dwarf dandelion, rough blazing star, cylindrical blazing star, blue toadflax, wild lupine, horsemint, racemed milkwort, panic grass, Venus looking glass, grasses, and sedges.

Management Recommendations

This species is the larval host plant for the state threatened northern blue butterfly. Disturbances to the sod should be avoided. Fire may play an important role in maintaining habitat, but never burn an entire site all at once. Active management to limit canopy closure may be needed if fire is not an option. The habitat of this species has been severely degraded and diminished.

Survey Methods

Random meander search covers areas that appear likely to have rare taxa, based on habitat and the judgment of the investigator.

  • Meander search

    • Survey Period: From third week of May to fourth week of July

References

Survey References

  • Elzinga, C.L., D.W. Salzer, and J.W. Willoughby. 1998. Measuring and Monitoring Plant Populations. The Nature Conservancy and Bureau of Land Management, Denver. BLM Technical Reference 1730-1. 477pp.
  • Goff, G.F., G.A. Dawson, and J.J. Rochow. 1982. Site examination for Threatened and Endangered plant species. Environmental Management 6(4): 307-316
  • Nelson, J.R. 1984. Rare Plant Field Survey Guidelines. In: J.P. Smith and R. York. Inventory of rare and endangered vascular plants of California. 3rd Ed. California Native Plant Society, Berkeley. 174pp.
  • Nelson, J.R. 1986. Rare Plant Surveys: Techniques For Impact Assessment. Natural Areas Journal 5(3):18-30.
  • Nelson, J.R. 1987. Rare Plant Surveys: Techniques for Impact Assessment. In: Conservation and management of rare and endangered plants. Ed. T.S. Elias. California Native Plant Society, Sacramento. 8pp.

Technical References

  • Gleason, H. A., and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and Adjacent Canada. Second edition. The New York Botanical Garden, Bronx. 910pp.
  • Gray, A. 1950. Gray's Manual of Botany; eighth ed. Van Nostrand Reinghold, New York. 1632pp.
  • Holmgren, N.H. 1998. Illustrated Companion to Gleason and Cronquist's Manual. Illustrations of the vascular plants of Northeastern United States and adjacent Canada. New York Botanical Garden, Bronx. 937pp.
  • Scoggan, H.J. 1978. The Flora of Canada. National Museum of Natural Science Publications Botany 4: 1711pp.
  • Voss, E.G. 1996. Michigan Flora. Part III. Dicots (Pyrolaceae-Compositae). Bulletin of the Cranbrook Institute of Science and University of Michigan Herbarium. 622pp.