Plants and Animals

Spinulum annotinum ssp. alpestre Northern stiff clubmoss

Key Characteristics

Decumbent, spreading clubmoss; aerial stems simple, forked at most once, branches ascending; sporangia born in terminal, sessile, strobili, 1 per upright shoot; sterile branches more or less rounded in cross-section; leaves in 5 or more ranks; and longest leaves 5.0 mm long, all but the lowest ascending, generally lacking even obscure teeth. Only recently distinguished from S. annotinum, which has leaves that are 6.0 to 9.0 mm long, spreading or reflexed, and toothed at least at the tip.

Status and Rank

US Status: No Status/Not Listed
State Status: SC - Special Concern (rare or uncertain; not legally protected)
Global Rank: G5TNR
State Rank: SNR - Not ranked


CountyNumber of OccurrencesYear Last Observed
Chippewa 6 2023
Keweenaw 1 1994
Luce 1 1974
Ontonagon 1 1958

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.


Known locations in Michigan are on Lake Superior dunes and sandy and rocky shores, and inland in the Upper Peninsula on low sandy ridges in peatlands.

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

Red maple (Acer rubrum), sedges (C. oligosperma, Carex stricta), leatherleaf (Chamaedaphne calyculata), reindeer lichen (Cladina spp.), trailing arbutus (Epigaea repens), wintergreen (Gaultheria procumbens), Michigan holly (Ilex verticillata), bog-laurel (Kalmia polifolia), tamarack (Larix laricina), running ground pine (Lycopodium clavatum), black spruce (Picea mariana), jack pine (Pinus banksiana), white pine (Pinus strobus), bracken fern (Pteridium aquilinum), Labrador-tea (Rhododenron groenlandicum), sphagnum moss (Sphagnum spp.), marsh fern (Thelypteris palustris), low sweet blueberry (Vaccinium angustifolium), small cranberry (Vaccinium oxycoccos), and velvetleaf blueberry (Vaccinium myrtilloides).

Management Recommendations

The biology and ecology of this species are poorly understood. Minimize development and fragmentation. When possible, leave large tracts of unharvested forests and allow natural processes to operate unhindered, including local natural disturbances such as windthrow that may benefit this 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

  • 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.
  • Palmer, D.D. 2019. Michigan’s Ferns and Lycophytes: A Guide to Species of the Great Lakes Region. University of Michigan Press, Ann Arbor, MI. 292 pp.
  • Pteridophyte Phylogeny Group. 2016. A community-derived classification for extant lycophytes and ferns. Journal of Systematic Evolution 54(6): 563–603.
  • Voss, E.G., and A.A. Reznicek. 2012. Field Manual of Michigan Flora. University of Michigan Press, Ann Arbor, MI. 1008 pp.