The sneezeweeds are often one of the last entries in a wildflower guidebook under yellow flowers. They don’t bloom until fall is starting. Autumn Sneezeweed is easy to spot in wet areas.
Helenium autumnale L.
August to November N Family: Asteraceae
Flower: Upper leaf nodes and branch tips put out flower stalks that thicken just under the flower head. The numerous sepals are light green, threadlike and curve upward around the center disk. Up to 20 triangular ray flowers surround the central disk. The rays range from yellow to orange and have three lobes on the outer edge. They stick straight out or slope away from the central disk. The central disk is a globular mound of yellow tube flowers.
Leaf: Alternate leaves are sessile looking like they are part of the stem going off because of the wings. The leaves are long with a single midvein. Many, especially lower leaves have teeth. The surfaces have a dotted appearance due to tiny glands on them.
Stem: One or several main stems grow up to 5 feet tall branching about half way up. The pale green to whitish stems are squared off and have green wings descending down from each leaf.
Root: The perennial roots are fibrous and shallow making the plant vulnerable to drought and fire.
Habitat: This plant likes very moist conditions preferring sunny edges of spring wetlands, ponds, creeks and lakes.
Poisonous: The plant contains a bitter lactone and can be toxic to grazing livestock.
Autumn Sneezeweed is a late blooming sunflower. It doesn’t open until the asters do, then blooms until autumn frosts drive most plants into dormancy for the winter.
This is an easy plant to identify. First, it likes growing in or near water. I find it around lakes and in wetlands.
Second, the flowers are so distinctive. No other yellow flower has the blunt triangle rays with lobes on the wide end. And the center is a pompom. For autumn Sneezeweed, the pompom is yellow.
Insects pollinate sneezeweed. The pollen doesn’t blow around making people sneeze. Where did the name come from?
Years ago Indians dried the plant. The dry leaves and flowers were crumbled in powder and used as a cold remedy snuff. This is sniffing pinches of powder. This caused sneezing.
Any of the sneezeweeds are bitter and avoided by livestock. Autumnal Sneezeweed is not a problem in any but low, wet pastures. In these it can grow in dense stands and be a problem.