Vascular Plants of North Carolina
Account for Purple Milkweed - Asclepias purpurascens   L.
Members of Apocynaceae:
Members of Asclepias with account distribution info or public map:
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Section 6 » Order Gentianales » Family Apocynaceae
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DistributionWidely scattered over most of the state, with no obvious pattern to the range, though presumably absent along the immediate coast, and thus far in the Mountains. (A specimen from Buncombe County had been misfiled and is A. quadrifolia, fide Sorrie).

This is primarily a Midwestern and more northerly species, ranging from southern New England and IA south to NC, northern GA, and northern LA.
AbundanceRare in the Piedmont. Very rare in the Coastal Plain, and may well be absent in many areas there. This is a Significantly Rare species, as named by the NCNHP. Their State Rank of S1? seems too conservative, and the website editors have assigned an S2 rank for it, as it occurs over a wide portion of the state.
HabitatThis is a species of damp ground in partial shade, such as openings in bottomlands, edges of wet thickets, swamp margins, and other damp and somewhat shaded ground. In some states it seems to show an affinity for circumneutral soils and can be found on prairies and other drier habitats; in NC, this affinity is not clear, but owing to its rarity and the fact that wet and shaded habitats are very common in the state on acidic to slightly acidic soils and the plants are missing, it may be that wet ground over soils derived from rocks such as diabase, amphibolite, gabbro, or marl/limestone might be prime habitats. There might be a few NC records not from wetland soils, and if so, these would certainly be found over circumneutral soils.
PhenologyBlooms from May to July, and fruits in June and July.
IdentificationThis is a rather stout-stemmed species of milkweed, quite a bit like Common Milkweed (A. syriaca) in form and leaves, but generally shorter, though still ranging to 2-2.5 feet tall. It has similar leaves to the other species, having at least 6 pairs of opposite leaves, with a very short petiole, and elliptic in shape, about 5-6 inches long and 2.5 inches wide. However, Purple Milkweed has among the most beautiful of all flower clusters of any species in the state -- one to several dense clusters (umbels) from the end of the stem and upper axils that feature deep rose-purple flowers in clusters about 2-3 inches broad. If seen in flower, it cannot be confused with any other species, and you will want to stop what you are doing to take some photographs! In leaf only, they can look a bit like short Common Milkweed plants, but that species normally does not grow in wet or damp places, in partial or mostly full shade. Thankfully, both species tend to grow in moderate to sizable clumps, rather than singly like a few milkweed species, and thus when in bloom the colonies are very showy.
Taxonomic CommentsNone

Other Common Name(s)None
State RankS1? [S2]
Global RankG5?
State StatusSR-T
US Status
USACE-agcpFACU link
USACE-empFACU link
County Map - click on a county to view source of record.
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Harry LeGrandGranville County; Picture Creek Diabase Barrens; 2 June 2020. GranvillePhoto_natural

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