Plants and Animals

Pterospora andromedea Pine-drops

species photo
Daniel C. Nepstad

Key Characteristics

Tall parasitic plant (30-100 cm) of coniferous woods; stems dark red with sticky glands, bearing numerous scale-like leaves; inflorescence with numerous nodding, bell-shaped white flowers and dark red sepals.

Status and Rank

US Status: No Status/Not Listed
State Status: T - Threatened (legally protected)
Global Rank: G5 - Secure
State Rank: S2 - Imperiled


CountyNumber of OccurrencesYear Last Observed
Alcona 1 1953
Alpena 3 2020
Antrim 1 1902
Baraga 1 2008
Chippewa 6 2015
Delta 1 1999
Dickinson 1 1981
Emmet 6 1999
Grand Traverse 1 1902
Iosco 2 1990
Keweenaw 9 2014
Leelanau 4 1992
Mackinac 5 2012
Marquette 2 1992
Mecosta 1 2022
Ontonagon 9 2021
Ottawa 1 1871
Presque Isle 5 2018
Schoolcraft 1 1929
St. Clair 2 1893

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.


Pine-drops is found in dry to moist woods dominated by pines or mixed conifers, usually with a well developed needle duff. Along Great Lakes shorelines, it is found in boreal forest and on forested backdunes.

Natural Community Types

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

Hemlock, white spruce, red pine, white pine, balsam fir, white cedar, large leaved aster, hepatica, spotted coral root, wintergreen, and various ferns.

Management Recommendations

Pine-drops is dependent upon a fungus that forms mycorrhizal relationship with a forest tree. Preservation of an intact forest is necessary to maintain this relationship, but research is likely required to determine how forest management practices influence the growth and distribution of the species.

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 September


Survey References

  • 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.