Bitter Sneezeweed,  July 30

     The edges of the greenway trail are starting to come alive again after the mowing and herbicide treatment of the previous month.  The mowers have been at constant work keeping about three feet of each side the trail low, but the workers are leaving a tall hedge of tall Johnson Grass which obscures about 5 or 6 feet of brown, vegetation looking quite dead before the undisturbed meadow and woods begin again.  One good result of the mowing and herbicide is that the poison ivy that had been taking over the area is now in retreat, only appearing as tree-climbing vines with barely any left on the ground.  Unfortunately, most of the wildflowers that were once so plentiful have disappeared, and there’s very little color on my hikes except for a little plant with yellow flowers that has made what I believe to be remarkable recoveries. 

    My plant identification app tells me that this plant is called Bitter Sneezeweed, with the scientific name of Helenium amarum. A bushy annual plant, Bitter Sneezeweed is in the Asteraceae, or Aster family along with daisies and sunflowers.  While the plant can grow to be up to 2 feet tall, the ones on the Greenway are low to the ground and line the edges of the path on the sunlit hill. Other names for this plant are Yellow Bitterweed, Yellowdicks, Slender-leaved Sneezeweed, Fine-leaved Sneezeweed and Yellow Dog-fennel.  This plant is native to my area of the continent having originated in the Southeast and Midwest United States where they are found in prairies, pastures, woodland openings, and along roadsides and trails.  The plant’s bright yellow flowers appear on naked stems above the plant’s foliage, and are long blooming from June straight through to October or frost.  This upright, bushy annual can spread to be over a foot in diameter. The ones on the trail are not very tall and are low to the ground possibly because of the recent mowing. 

     Some references I encountered recommend planting Bitter Sneezeweed in your gardens or in hanging flower pots. They claimed that it also makes a striking appearance in naturalistic prairies and meadows where it will provide a lovely edge.  It is a low maintenance plant that can tolerate dry to medium water and sandy to gravelly well-drained soil.  Bitter Sneezeweed flourishes in full sun to partial shade. Removing the spent flowers, or dead-heading the plants, will encourage additional blooms.  The flowers are a main attraction of this plant because the leaves of the Bitter Sneezeweed can be described as being “linear filiform”. This means that they are very thin, almost thread-like, and in some cases not more than 1/8th of an inch wide.  The leaves of the Bitter Sneezeweed plant can grow to be up to 3 inches long, but are usually about an inch or so. They are alternate and are located on light green and nearly hairless stems.  Leaves are light to medium green, or a grayish blue.  The lower leaves often wither away before the flowerheads bloom.

     A tiny Bitter Sneezeweed flower might look like a petal flower but it is in fact a cluster of several flowers all at once.  Looking like small yellow daisies, they are “composite” flowers, which means that they don’t have petals, but instead have 5 to 10 “ray flowers” which are actually individual flowers growing around a central disk. The disk is also made up of tiny tube flowers, called “disk flowers” that are clustered together into a ball.  Many members of the Asteraceae family, like Sunflowers, true Daisies, and Asters are composite flowers.  Some ray flowers produce their own seeds and this might be the case with Bitter Sneezeweed, but others, like Sunflowers have ray flowers that are sterile.  Bitter Sneezeweed is a hermaphrodite plant, meaning that it has both male and female organs and is pollinated by bees, lepidopterae (moths and butterflies) and the like.   Rays of the Bitter Sneezeweed are golden-yellow in color and each is wider at the top edge than where it joins the disc. The whole composition is held together by leaf-like structures that join the composite flowers to their stems.  These are called phyllaries. When you look really close at a composite flower of the Bitter Sneezeweed plant you can see that the outer edge of each ray flower has a three-lobed tip.  Rays often droop downward from the spherical disc.  Bitter Sneezeweed is spread by seeds which may be dispersed by animals. The plant grows a shallow root system consisting of a short branching taproot.

     Depending on who you are and where you live, Bitter Sneezeweed is either an upright aromatic bushy annual that attracts a large variety of insects and provides food in the form of seeds and seedheads for the Greater Prairie Chicken, or a plant that is an invasive species threatening not only livelihoods but also the environment worldwide!  All parts of the plant contain glycoside gudaldin and sesquiterpene lactone helenalin which are poisonous to fish and dogs. The plant also contains lactone tenulin, which gives it a very bitter taste.  These chemicals can cause toxic symptoms like disorientation and drooling in grazing animals. Some claim grazing on the plant can even kill horses if eaten in sufficient quantities although no one has actually reported this.  The plant is very bitter and this causes problems in the dairy and meat industries.  Cows eating even a small amount of the plant produce milk so bitter that no one wants to drink it, and the while the pollen is a valuable food to pollinators like native sweat bees, native wasps, beetles and butterflies, honey made from its pollen is also too bitter to sell. Sesquterpene lactone, makes the plant toxic to most mammals although it is so bitter it is rarely if ever eaten in quantities to be deadly. But if ingested, the plant will make the meat of grazing animals unpalatable if they are slaughtered on the range.

    Bitter Sneezeweed has little medicinal value. The most important use the plant has is that when the flower heads are dried and grounded up they can be used as snuff that will make you sneeze.  The name given by the Menominee Indians of Wisconsin to Helenium autumnale, its perennial cousin, is “alatci’a ni’tcikun” which mean “sneezing spasmodically”.  In some cultures sneezing is and was desirable.  Sneezing was considered a good way to rid oneself of evil spirits.  Sneezing also helps unclog your nose if you have a cold or respiratory allergies and Native people snorted the plant to treat blocked sinuses.  Snuff made from the Bitter Sneezeweed has also been used by miners of European descent in Michigan to help clear their sinuses of mining dust.  Native Americans also made a decoction of the entire plant to use in their sweat lodges to treat dropsy and swelling. 

    Bitter Sneezeweed is native to parts of Mexico and some American states like Texas, where unfortunately a lot of the grazing land is now covered by the plant.  It was introduced to Europe in 1729 as an ornamental plant where it made quite a hit. British and German horticulturalists hybridized the plant so that rays of the blooms can vary from yellow, to orange and mahogany brown. There are even some hybrids that are bright red and gardeners still win awards of Garden Merit from the Royal Horticulture Society for their plants’ reliable performance in gardens.

     There are at least 40 species of the Helenium found in North, South and Central America, and some of the European hybrids have made their way back to the gardens of the United States. While some states like Virginia protect and value other species of Helenium by listing them on the endangered species list, states like Michigan and California consider Bitter Sneezeweed an invasive species rather than one of our underutilized native wild flowers. Bitter Sneezeweed is not always a plant that is welcomed and describe it as an opportunistic colonizer that will quickly spread. Recently the plant found its way to northern states like Connecticut, Maryland, and Massachusetts where it may affect the dairy industry. In 1953 the plant was spotted in Queensland, Australia, probably carried there by aircraft, or associated equipment, although now if you want to grow the plant to decorate your garden you can purchase seeds online.  Queensland feared for its grazing animals and considered Bitter Sneezeweed an environmental weed that needed to be eradicated.  Believing that they had successfully destroyed all Sneezeweed plants in their state in 2002, the Australians are dismayed to discover that plants are still being identified, although they remain in low numbers.

     Bitter Sneezeweed is pollinated by insects and not by the wind like Ragweed.  The plant does not have small pollen grains and will not cause hay fever symptoms. Its blooms are particularly valuable to pollinators in late summer and autumn when other flowers have died.  The name of the genus, “Helenium”, was given to these plants in honor of Helen of Troy. The myth goes that these flowers sprang up when Helen’s tears touched the ground. Since the plant originated in the Americas, and Helen came from Sparta and was carried off to Troy in what is now Turkey, there’s a high probability that this claim is totally false.   

    Researchers continue to investigate the use of the chemicals in Bitter Sneezeweed as a low risk insecticide for crops like corn and potatoes.  Possibly in the future someone will succeed.  If you want to learn more about this fascinating plant, visit the references below.  Then let me know what you think: Is Bitter Sneezeweed a dangerous invasive plant, or is it a lovely native wildflower?

Britannica, “Ray Flower”, https://www.britannica.com/science/ray-flower

Sue Trull, U.S. Forest Service, Plant of the Week, “Common sneezeweed (Helenium autumnale. L. var. autumnale)” https://www.fs.fed.us/wildflowers/plant-of-the-week/helenium_autumnale_autumnale.shtml

MISIN, Midwest Invasive Species Information Network, Michigan State Universiry, “Bitter Sneezeweed (Helenium amarum)”, http://www.misin.msu.edu/facts/detail/?project=misin&id=133&cname=Bitter%20sneezeweed

Charlie Nardozzi, Public PBS, NPR, The Colin McEnroe Show, “Connecitcut Garden Journal: Sneezeweed”, 2021,  https://www.ctpublic.org/environment/2019-08-22/connecticut-garden-journal-sneezeweed

Sue Trull, U.S. Forest Service, Plant of the Week, “Common Sneezeweed, Helenium autumnale, var. autumnale)” https://www.fs.fed.us/wildflowers/plant-of-the-week/helenium_autumnale_autumnale.shtml

CABI: Invasive Species Compendium, Detailed coverage of invasive species threatening livelihoods and the environment worldwide, “Helenium amarum (Bitterweed)” https://www.cabi.org/isc/datasheet/121130

Plants of Texas Rangelands, “Bitter sneezeweed, Basin Sneezeweed, 2022, https://rangeplants.tamu.edu/plant/bitter-sneezeweed/#:~:text=A%20sesquiterpene%20lactone%20is%20responsible,enough%20to%20produce%20clinical%20signs.

Pat Chadwick, Piedmont Master Gardeners: Sharing Knowledge, Empowering Communities, “Helenium – A great choice for the late summer garden” 2017, https://piedmontmastergardeners.org/article/helenium-a-great-choice-for-the-late-summer-garden/#:~:text=Helenium%20may%20be%20one%20of,it%20was%20introduced%20in%201729.

J. T. Arnason, et al., National Library of Medicine, “Mode of action of the sesquiterpene lactone, tenulin, from Helenium amarum against herbivorous insects”, 1987, https://pubmed.ncbi.nlm.nih.gov/3430166/