Plants and Animals

Agalinis skinneriana Skinner's gerardia

species photo
Susan R. Crispin
species photo
Susan R. Crispin

Key Characteristics

Annual forb (20-50 cm) of lakeplain prairies; stem slender with sparse, strongly ascending branches, bearing linear opposite leaves; flowers white to light pink arising on long stalks (7-30 mm) from leaf axils on the upper main stem.

Status and Rank

US Status:
State Status: E - Endangered (legally protected)
Global Rank: G3G4 - Rank is uncertain, ranging from vulnerable to apparently secure
State Rank: S1 - Critically imperiled

Occurrences

CountyNumber of OccurrencesYear Last Observed
St. Clair11994

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 in lakeplain prairie landscapes.

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

Bluejoint grass, cordgrass, rush, sedges, twig-rush, shrubby cinquefoil, swamp milkweed, big bluestem, Indian grass, Sullivant's milkweed, purple milkweed, swamp thistle, eastern prairie fringed orchid, marsh blazing star, whorled loosestrife, grass-of-Parnassus, smooth hedge nettle, swamp rose, Missouri ironweed, little bluestem, three-awned grass, colic root, prairie willow, seedbox, and short-fruited rush.

Management Recommendations

Maintain hydrological and natural disturbance regimes. This species most likely requires open conditions. Prevent woody plant encroachment by using prescribed fire or manual brush removal. Soil disturbance also may be needed. Much of this habitat has been lost and degraded via conversion to agriculture, development, alterations of hydrology via drains and also through fire suppression.

Survey Methods

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

  • Meander search

    • Survey Period: From third week of August to second week of September

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.
  • 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.
  • Swink, F. and G. Wilhelm. 1994. Plants of the Chicago Region, 4th ed. Indiana Academy of Science, Indianapolis. 921pp.
  • Voss, E.G. 1996. Michigan Flora. Part III. Dicots (Pyrolaceae-Compositae). Bulletin of the Cranbrook Institute of Science and University of Michigan Herbarium. 622pp.