Vascular Plants of North Carolina
Account for Schweinitz's Sunflower - Helianthus schweinitzii   Torrey & A. Gray
Members of Helianthus with account distribution info or public map:
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Section 6 » Order Asterales » Family Asteraceae
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AuthorTorrey & A. Gray
DistributionPiedmont only, and limited to the central and west-central portions, east only to Guilford, Randolph, Montgomery, and Richmond counties.

Endemic to NC and northern SC. No records from VA.
AbundanceUncommon to locally fairly common; a few populations contain 1,000 or more plants. Several populations have been augmented by transplanting, others by vigorous habitat management, including fire. Most are signed as "No Mow" or restricted mow areas. The species is apparently proposed for downlisting or de-listing, as populations are quite numerous, though there is still some loss to mis-management of roadside populations. Currently, it is Federal and State Endangered, but in reality it is not endangered at the present time.
HabitatWooded borders, roadsides, powerline clearings; open woodlands with Blackjack Oak (Quercus marilandica), Post Oak (Q. stellata), hickories, and native grasses. Original habitats likely included prairie-like openings, probably kept open by fire (natural and Indian-set). However, reintroduced fire to some populations has not been a panacea in each case, and so it may be that some form of physical disturbance -- such as roadside mowing -- is needed.
PhenologyFlowering and fruiting late August-October.
IdentificationThis tall sunflower routinely reaches 6 feet high and sometimes 9 feet. Stems are rough-hairy. Leaves are opposite, up to 7 inches long, lance-shaped, lack teeth, margins generally curled under, very rough textured above (like sandpaper), and softly white-hairy beneath. Heads are showy, with yellow rays and disks. Giant Sunflower (H. giganteus) has a red-tinged stem (vs. green) and its leaf margins are not curled under.
Taxonomic CommentsNone

Other Common Name(s)None
State RankS3
Global RankG3
State StatusE
US StatusLE
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