Helenium - Sneezeweed

Helenium is a genus of about 40 herbaceous flowering plants in the daisy family Asteraceae, native to North America and Central America. They bear yellow or orange daisy-like flowers. A number of these species (particularly Helenium autumnale) are commonly known as sneezeweed because of the common allergenic reaction experienced by people in their vicinity.


Species
Helenium amarum is a species of annual herb in the daisy family known by the common names yellowdicks, yellow sneezeweed, and bitter sneezeweed. It is native to much of the southeastern United States and northern Mexico, and it is present elsewhere in North America as an introduced species. This is a multibranched bushy erect plant reaching 20 to 70 centimeters in height and thickly foliated in narrow to threadlike leaves. The tops of stem branches hold inflorescences of many daisylike flower heads. Each head has a rounded center of golden yellow disc florets and a fringe of usually lighter yellow ray florets which are reflexed away from the center. The fruit is a tiny achene about a millimeter long. This herb is weedy in some areas. The plant is somewhat toxic to mammals and insects due to the presence of the lactone tenulin.

Helenium autumnale - Common sneezeweed is a flowering plant native to North America. Other common names include Helen's flower, bitterweed, and false sunflower.

Helenium bigelovii - The daisylike plant Helenium bigelovii is known as Bigelow's sneezeweed. It is a plant of meadows and marshes that bears flowers that are usually bright yellow in color. It grows in moist areas. It is found at moderate elevation in the foothills and low mountains of California. Cultivars are raised as ornamentals.

Helenium puberulum is a species of flowering plant in the daisy family known by the common name rosilla. It is native to California and Baja California, where it can be found in moist habitats such as riverbanks and meadows. This is an annual or perennial herb varying in size and shape from a low stem with few branches to an erect, spindly stem nearing 1.5 meters tall. Most of the leaves are on the lower part of the plant, with the upper occupied by naked peduncles bearing inflorescences of several daisylike flower heads. Each head is mainly a spherical bunch of disc florets which are yellow when new and darken with age. Some heads also have a few to many yellow ray florets. The fruit is a hairy achene one to two millimeters long.

Helenium bolanderi is a species of flowering plant in the daisy family known by the common name coastal sneezeweed. It is native to the coastline of Oregon and northern California. This is a daisylike perennial herb varying in size from 20 centimeters to well over a meter in height. It has a generally unbranched, erect stem with oval-shaped leaves. The flowers arise on naked peduncles with one to three flower heads per inflorescence. Each flower head has a fringe of golden yellow ray florets reflexed away from a rounded center of disc florets in shades of yellow, red, or brown. The fruit is a tiny, hairy achene a few millimeters long.

Helenium flexuosum

Helenium glaucum

Helenium urmenetae

Helenium hoopesii

Helenium atacamense

Helenium microcephalum

Helenium virginicum

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Selected species
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