The common name comes not from any pollen allergy that hay-fever victims might suffer (for wind-pollination is not characteristic of plants with showy flowers), but from use of the dried, pulverized heads to make a snuff that promotes sneezing.
1. Leaves very numerous, crowded, less than 2 mm broad; stems not winged (may be angled or ridged); annual.
1. Leaves not crowded, broader; stem with green wings the length of the internodes; perennial.
2. Disk corollas with 5 yellow lobes; ray flowers pistillate.
2. Disk corollas with 4 brown or purple lobes; ray flowers sterile.
All species found in Helenium
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. December 16, 2017. http://www.michiganflora.net/genus.aspx?id=Helenium.