Sawtooth Sunflower (Helianthus grosseserratus) can be distinguished from other Sunflowers by its red, smooth stems can be aggressive and may not be suitable for small landscape plantings.  Can reach 6 feet or more but generally near 3 to 4 feet. Large yellow (sometimes whitish) flowers with serrated leaves.

Helianthus is from the Greek word helios meaning "sun" and anthos for "flower".

 

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