Stem hairy or rough --185.

185a. Leaves hairy beneath, rough above, lanceolate
=Sunflower, Helianthus giganteus.=

185b. Leaves rough on both sides, elongated
=Sunflower, Helianthus maximiliani.=

186a. Leaves sessile (5-15 dm. high) --187.

186b. Leaves petioled, or narrowed at the base into a petiole (5-30
dm. high) --189.

187a. Leaves wedge-shape at the base
=Sunflower, Helianthus doronicoides.=

187b. Leaves rounded at the base --188.

188a. Stem glabrous or nearly so
=Sunflower, Helianthus divaricatus.=

188b. Stem densely and softly hirsute
=Sunflower, Helianthus mollis.=

189a. Stems rough, pubescent, or hispid --190.

189b. Stems glabrous or nearly so --193.

190a. Leaves narrowly lanceolate, more than 5 times as long as wide
=Sunflower, Helianthus giganteus var. subtuberosus.=

190b. Leaves ovate-lanceolate, not more than 4 times as long as
wide --191.

191a. Leaves rounded at base, above the petiole
=Sunflower, Helianthus hirsutus.=

191b. Leaves narrowed to the base --192.

192a. Bracts of the involucre spreading
=Jerusalem Artichoke, Helianthus tuberosus.=

192b. Bracts all appressed =Sunflower, Helianthus laetiflorus.=

193a. Heads 3 cm. wide or less, including the rays
=Sunflower, Helianthus microcephalus.=

193b. Heads 4 cm. wide or more, including the rays --194.

194a. Leaves narrowed at the base into a winged petiole --195.

194b. Petiole slender, not winged
=Sunflower, Helianthus decapetalus.=

195a. Leaves green on both sides; bracts longer than the disk
=Sunflower, Helianthus tracheliifolius.=

195b. Leaves paler below than above; bracts not longer than the disk
--196.

196a. Leaves minutely pubescent beneath
=Sunflower, Helianthus strumosus.=

196b. Leaves conspicuously downy beneath
=Sunflower, Helianthus strumosus var. mollis.=

197a. Leaves all basal, the flowers on scaly stalks (2-8 dm. high;
flowers whitish, in spring) =Coltsfoo