Asclepias hirtella
Tall green milkweed
Image of Asclepias hirtella

Photo by Ryan P. O'Connor 

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Key Characteristics

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

Occurrences

County NameNumber of OccurrencesYear Last Observed
Bay21984
Huron52015
Jackson21981
Kalamazoo12001
Monroe32014
Muskegon22005
Newaygo22005
St. Joseph22006
Tuscola41993
Wayne11991
Distribution map for Asclepias hirtella

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

Grows in wet-mesic to dry sandy loam soils at inland sites as well as on alkaline clay in lakeplain prairies.

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

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.

Management

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.

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 26, 2017]

More Information

See MNFI Species Abstract

References

Survey References

Technical References