Oplopanax horridus
Devil's club
Image of Oplopanax horridus

Photo by John V. Freudenstein 

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Key Characteristics

Tall spiny shrub of the Isle Royale archipelago; entire plant covered with sharp spines; leaves palmately lobed and sharply-toothed on the margins; flower tiny and white, fruit a red berry, borne on the tips of branches in round clusters.

Status and Rank

  • State Status: T
  • State Rank: S2
  • Global Rank: G5


County NameNumber of OccurrencesYear Last Observed
Distribution map for Oplopanax horridus

Updated 5/15/2018. 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.


Occurs in the shaded understory of paper birch or birch-balsam fir forest, becoming especially dense in wooded ravines and openings.

Specific Habitat Needs

needed in Boreal forest

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

Balsam fir, yellow birch, mountain ash, yew, bunchberry, bluebead lily, goldthread, twinflower, expanded woodfern, stiff club-moss.


Known only on Isle Royale in Michigan, where no particular protection of management is required.

General Survey Guidelines

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

Survey Methods

Page Citation

Michigan Natural Features Inventory. 2007. Rare Species Explorer (Web Application). Available online at http://mnfi.anr.msu.edu/explorer [Accessed Sep 22, 2018]


Survey References

Technical References

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