July - November
0.9 - 2.0
May be confused with Vernonia texana when sterile, but can be distinguished by its leaves which are linear and have edges which curl under, while those of Vernonia are strongly lance shaped and curl inward.
Experiments by Nichols (1934) indicated that cold stratification slightly increased and speeded germination. Steffen (1997) reported improved germination with cold/stratification. Seeds average approximately 533,000 seeds/lb.
Helianthus angustifolius is a preferred plant and considered of high value as cattle forage, grazed throughout the season. Deer browse the foliage and quail and doves eat the seeds (Grelen and Hughes 1984). The following information is for the genus Helianthus: Animals that eat its seeds: Mourning dove, Eastern white-winged dove, Bobwhite quail, Gambel quail, Redwing blackbird, Crow, Eastern goldfinch, Purple grackle, Meadowlark, White-breasted nuthatch, Pyrrhuloxia, English sparrow, Grasshopper sparrow, Savannah sparrow, Tree sparrow, Eastern pocket gopher, Meadow mouse and various other species in the east. Animals that eat the plant: Muskrat, Antelope, White-tailed deer (Martin et al. 1951). This plant is a special value to native bees.
A prairie species common in ditches and wet, disturbed areas of Louisiana and southeast Texas, but is also one of the most common forbs on many upland sites, including dry sandy ridges. Very aggressive in prairie restorations; consequently, it may be best to introduce this species a few years after completing a restoration.
Flood plains and bottomlands.