Plants and Animals
Trillium sessile Toadshade
Key Characteristics
Medium-sized forb (40 cm) of rich woods; leaves broadly oval (3-6 cm wide), sessile, strongly mottled; flowers sessile, dark red, petals short (> 4 cm).
Status and Rank
US Status: No Status/Not Listed
State Status: T - Threatened (legally protected)
Global Rank: G5 - Secure
State Rank: S2S3 - Rank is uncertain, ranging from imperiled to vulnerable
Occurrences
| County | Number of Occurrences | Year Last Observed |
|---|---|---|
| Berrien | 7 | 2022 |
| Cass | 1 | 2018 |
| Kalamazoo | 1 | 2002 |
| Lenawee | 6 | 2024 |
| Oakland | 1 | 1918 |
| St. Joseph | 1 | 1947 |
| Van Buren | 1 | 1981 |
| Washtenaw | 2 | 1999 |
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
Toadshade is found in floodplains and mesic forests, especially moist ravines, rich moist woods and bluffs, and is especially frequent on limestone derived soils.
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
Beech, sugar maple, basswood, tulip poplar, white ash, bitternut hickory, wild leek, cut-leaved toothwort, dutchman's breeches, yellow trout lily, Virginia waterleaf, false rue anemone, woodland phlox, common trillium, ginseng, goldenseal, pawpaw, blue ash, red ash, Kentucky coffeetree, wahoo, false rue anemone, bluebells, and sessile trillium.
Management Recommendations
Conserve hydrology of river system and corresponding cyclical floodplain regime. Maintain healthy intact, mature floodplain forests and minimize forest fragmentation. Monitor and control invasive species, particularly garlic mustard and dame's rocket. When possible, leave large tracts of unharvested forests and allow natural processes to operate unhindered.
Survey Methods
Random meander search covers areas that appear likely to have rare taxa, based on habitat and the judgement of the investigator.
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Meander search
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Survey Period: From first week of April to third week of May
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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
- Braun, E. L. 1967. The Monocotyledoneae of Ohio. Cat-tails to Orchids. Ohio State University Press, Columbus. 464pp.
- Case, F.W., Jr. and R. B. Case. 1997. Trilliums. Timber Press, Portland. 285pp.
- Deam, C. C. 1940. Flora of Indiana. Department of Conservation, Indianapolis. 1236pp.
- 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.
- Mohlenbrock, R.H. 1986. Guide to the Vascular Flora of Illinois. Southern Illinois University Press, Carbondale. 507pp.
- Swink, F. and G. Wilhelm. 1994. Plants of the Chicago Region, 4th ed. Indiana Academy of Science, Indianapolis. 921pp.
- Voss, E. G. 1972. Michigan Flora. Part I. Gymnosperms and Monocots. Bulletin of the Cranbrook Institute of Science and University of Michigan Herbarium. 488pp.