Arnica lonchophylla
Longleaf arnica

Key Characteristics

Small perennial forb of Isle Royale; leaves lanceolate and hairy, becoming smaller and fewer toward the apex of the mostly leafless stem; flowers sunflower-like, 4-6 cm wide.

Status and Rank

  • State Status: E
  • State Rank: S1
  • Global Rank: G5

Occurrences

County NameNumber of OccurrencesYear Last Observed
Keweenaw11997
Distribution map for Arnica lonchophylla

Updated 1/31/2017. 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

Found on calcareous basaltic lakeshore cliffs near Lake Superior on Isle Royale. Long known from northeastern Minnesota and adjacent Ontario, it was first discovered in Michigan in 1997.

Natural Community Types

Methodology

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.

Feel free to send questions and comments to Brad Slaughter at slaugh14@msu.edu.

Associated Plants

Ashy whitlow grass, slender cliff-brake, encrusted saxifrage, early saxifrage, harebell, and white cedar.

Management

The specific requirements of this species are unknown, but the primary need is likely conservation of its fragile cliff habitat and protection from trampling.

General Survey Guidelines

Random meander search covers areas that appear likely to have rare taxa, based on habitat and the judgement 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 Mar 24, 2017]

References

Survey References

Technical References