|Tall green milkweed|
Photo by Ryan P. O'Connor
Perennial forb (40-100 cm) of savannas and prairies; leaves alternate, long and narrow; flowers green, borne in axillary clusters.
Status and Rank
- State Status: T
- State Rank: S2
- Global Rank: G5
|County Name||Number of Occurrences||Year Last Observed|
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.
Grows in wet-mesic to dry sandy loam soils at inland sites as well as on alkaline clay in lakeplain prairies.
Natural Community Types
- Lakeplain wet prairie
- Mesic sand prairie
- Lakeplain wet-mesic prairie
- Wet-mesic prairie
- Wet-mesic sand prairie
- Dry-mesic prairie
- Oak openings
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.
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, mountain mint.
Conserve habitat and 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. Significant increases in vegetative and reproductive vigor have been observed following early spring and fall burns; late spring burns and summer can damage plants. Much of this habitat has been lost and degraded via conversion to agriculture, development, alterations of hydrology via drains and fire suppression. Many prairie remnants are also vulnerable to common right-of-way maintenance activities such as mowing, herbiciding, and bulldozing.
General Survey Guidelines
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 fourth week of June to third week of August
More InformationSee MNFI Species Abstract
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- 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.