Colors

Data mode

Account

Login
Sign up

Support FSUS...

We've finished our 2024 fundraiser. Many thanks to those who have given! It's not too late to support us (click here)...

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

Copy permalink to share

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].