Helianthus genus --- aster subfamily 3.2
Aster 3.1 (Genus A to F) -- Aster 3.2 (Genus G to O) -- Aster 3.3 (Genus P to R) -- Aster 3.4 (Genus S to Z)
common sunflower (Helianthus annuus) -- in July -- Orchard Cove Trail, Lory State Park, CO
common sunflower (Helianthus annuus) -- in August -- Arapaho Bend, Fort Collins Natural Area, CO
sawtooth sunflower (Helianthus grosseserratus) -- in September -- Cloudcroft, Lincoln National Forest, NM
Maximilian sunflower (Helianthus maximiliani) -- in September -- Big Thompson Ponds State Wildlife Area, CO
Nuttall's sunflower (Helianthus nuttallii) -- in June -- Well Gulch Nature Trail, Lory State Park, CO
Nuttall's sunflower (Helianthus nuttallii) -- in August -- Riverbend Ponds, Fort Collins Natural Area, CO
stiff sunflower (Helianthus pauciflorus) -- in July -- Buffalo Pass Road, Jackson County, CO
prairie sunflower (Helianthus petiolaris) -- in August -- Bluff Lake Nature Center, Denver Area, CO
prairie sunflower (Helianthus petiolaris) -- in May -- San Juan County, Utah
little sunflower (Helianthus pumilus) -- in June -- Lory State Park, CO
little sunflower (Helianthus pumilus) -- in August -- Timber Trail, Lory State Park, CO
little sunflower (Helianthus pumilus) -- in August -- Indian Meadows North, Poudre Canyon, Larimer County, CO