Plants and Animals
Asclepias ovalifolia Dwarf milkweed
Slender perennial forb (20-60 cm) of oak-pine barrens; leaves opposite on short petioles, usually limited to 4-6 pairs; flowers white to green, borne in clusters with long stalks.
Status and Rank
State Status: E - Endangered (legally protected)
Global Rank: G5? - Secure (inexact)
State Rank: S1 - Critically imperiled
|County||Number of Occurrences||Year Last Observed|
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.
Long known from southern Menominee County, where it occurs in oak-pine barrens (oak-jack pine savanna). A disjunct population was discovered in a Lake County barrens in 2016.
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.
Black oak, white oak, jack pine, red maple, black cherry, pin oak, hickory, sassafras, service berry, New Jersey tea, sweetfern, beaked hazelnut, wintergreen, huckleberry, sand cherry, dwarf chinquapin oak, low sweet blueberry, little bluestem, big bluestem, sky-blue aster, false foxglove, tickseed, nut grass, flowering spurge, hair grass, tall sunflower, dwarf dandelion, blazing star, wild bergamot, goats-rue, wood betony, needle grass, and birdfoot violet.
This species likely requires natural disturbances associated with prairie habitat such as prescribed fire or brush removal to prevent woody plant succession. Much of this habitat type has been lost or severely degraded.
Random meander search covers areas that appear likely to have rare taxa, based on habitat and the judgment of the investigator.
Survey Period: From first week of July to fourth week of July
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- 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.