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Support the Flora of the Southeastern US

2024 has been a banner year for making the best flora we can imagine. We've created:
With financial support from people like you, we are aiming even higher in 2025. Together we can accomplish all this: Vote on our 2025 priorities
  • Add Global Conservation Ranks (GRanks) vote
  • Professional graphic keys (polyclaves) to individual families/genera vote
  • 2 new FloraQuest apps: Florida & Mid-South vote
  • Image overlays highlighting diagnostic characters with arrows vote
  • iNaturalist integration in FloraQuest vote
Write-in vote: vote
We've set a goal of recruiting 200 ongoing supporters to donate $15 or more each month in 2025. Please help us reach this goal and make next year's flora even better:

Click the number at the start of a key lead to highlight both that lead and its corresponding lead. Click again to show only the two highlighted leads. Click a third time to return to the full key with the selected leads still highlighted.

Key to Helianthus

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1 Leaves basally disposed, the plants scapose to subscapose, the stem leaves relatively few (with 2-8 nodes below the inflorescence), those on the upper stem opposite or alternate, strongly reduced upward in size as compared to the persistent basal leaves; [section Atrorubentes]
1 Leaves cauline, plants leafy the length of the stem, the stem leaves many (with 10 or more nodes below the inflorescence), basal leaves lacking (at least at anthesis).
  2 Plant a tap-rooted annual (rarely surviving a second year)
  2 Plant a perennial from crown buds or rhizomes, the roots sometimes tuberous-thickened; [section Atrorubentes].