Flora of the Hawaiian Islands
Dicotyledon Literature for Tithonia diversifolia
Lorence & Wagner, 2020.
   Asteraceae -- The Sunflower Family Bibliography
      Tithonia diversifolia

Common name(s): Mexican sunflower, tree marigold
General Information
DistributionNative to Mexico, naturalized in many tropical countries.In the Hawaiian Islands, naturalized on Kaua`i, O`ahu, Lana`i, Maui, Hawai`i.

Shrub, 2‒5 m tall, wood very soft, villous and aromatic, glandular to subglabrate.
Leaves petiolate; blade palmately 3‒5-lobed, 8‒15(‒22) cm long, 6‒10(‒12) cm wide, gradually tapering to a petiole 2‒4 cm long.
Heads large and showy; ray florets 7‒21 per head, rays yellow, 3‒6 cm long; disk florets numerous, corollas ca. 15 mm long; pappus of 2 persistent awns ca. 5 mm long, and a ring of scales 2‒3 mm long.
Achenes flattened, ca. 5 mm long, pubescent.
2n = 30, 34.
Nancy Khan