Plants and Animals

Lonicera involucrata Black twinberry

species photo
Susan R. Crispin
species photo
Emmet J. Judziewicz
species photo
Emmet J. Judziewicz
species photo
Emmet J. Judziewicz

Key Characteristics

Erect shrub of Isle Royale; opposite leaves oval with a sharp-pointed tip; yellow, funnel shaped flowers borne in pairs on long stalks from the leaf axils, enveloped by 2 pairs of leaf-like bracts, which expand and enclose the purple-black berries when fruiting.

Status and Rank

US Status:
State Status: T - Threatened (legally protected)
Global Rank: G5T4T5
State Rank: S2 - Imperiled

Occurrences

CountyNumber of OccurrencesYear Last Observed
Keweenaw161994

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

Black twinberry is found in cool woodland habitats, including swampy woods and thickets, bogs, streambanks, and shores.

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

White cedar, white spruce, balsam fir, trembling aspen, paper birch, red-osier dogwood, tag alder, big leaf aster, fringed polygala, wild sarsaparilla, twinflower, and goldthread.

Management Recommendations

Maintain intact habitat as well as hydrological regime. Likely sensitive to heavy logging and excessive canopy removal.

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 first week of June to fourth week of August

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.
  • Hulton, E. 1968. Flora of Alaska and neighboring territories. Stanford University Press, Palo Alto. 1008 pp.
  • 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.