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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 Arctium

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1 Inner phyllaries constricted above the middle, widened toward the truncate (or rarely acuminate) apex
1 Inner phyllaries never constricted above the middle, gradually narrowing toward the acute to acuminate apex.
  2 Petiole of the basal leaves solid; heads in the upper part of the inflorescence on peduncles > 2.5 cm long; heads corymbosely arranged on the main branches
  2 Petiole of the basal leaves hollow (at least toward its base); heads in the upper party of the inflorescence on peduncles < 2 cm long; heads racemosely arranged on the main branches.
    3 Heads 1.1-2.4 cm in diameter; heads on terminal branches sessile or pedunculate; middle phyllaries < 1.8 mm wide; corolla with glandular hairs
    3 Heads 1.9-2.9 cm in diameter; heads on terminal branches sessile; middle phyllaries (1.6-) 1.7-2.5 mm wide; corolla glabrous