If you’ve been following my website for a while (and if so, thank you!), you’ve probably noticed that I have a lot of ‘favorite’ native flowers. It’s true. I’m glad I don’t really have to choose a favorite, but, if I did, Rudbeckia submentosa would be in the running for top spot. I find myself edgy with anticipation every July as I walk or ride down my horse trail. Will they bloom as profusely as last year? Will they really be as spectacular as the first yearI found them? You see, although they have never failed to bloom, in years with ample rainfall their show is just stunning. They simply light up both sides of my trail with a profusion of tall sunshine yellow blooms that last until frost. The drought years bring fewer flowers but perhaps they are even more welcome then. Either way, it is one of the most pleasing sites anyone could ask for and it never fails to cause me to smile or even laugh out loud with happiness at just seeing them again.
Latin Name/Common Name- The name Rudbeckia was given to the black-eyed Susan family by Linnaeus in order to commemorate a Swedish father and son, both named Olaus (Olof) Rudbeck. The father gained distinction in many fields, first becoming famous for discovering the lymphatic gland and the bodies circulation of lymphatic fluid. He was a professor of medicine, an excellent musician, linguist and botanist He founded the Uppsala Botanic Garden. His son, Olof Rudbeck the Younger was also a distinguished professor of medicine at Uppsala. There he was responsible for anatomy, botany, zoology and pharmacology. I found their story and connection with Linnaeus very interesting and I recommend you read about it. In a nutshell, Olaf the Younger assisted his father with a monumental botanical work known as the Campus Elysii, a survey of all plants known at the time with thousands of woodcut illustrations. Most of this life long work burned, along with notes and other related items in the terrible fire of 1702- which destroyed most of Uppsala. I cannot imagine how devastating this must have been and Olof the Elder died only a few months later. The son continued the work, traveling to Lapland on an important scientific expedition and after working for years on the related materials, his work was also destroyed in a fire. Years later,an impoverished Linnaeous came to Uppsala and was befriended by Olaf the Younger (now old) who was impressed with his studies. Linnaeus honored the relationship in 1753 by naming this beautiful genus for him.
The word ‘submentosa’ means below (sub) and hairy (tosa).
Sweet black-eyed Susan, the common name, comes from the black (really brown) center of the flower and the mild anise like scent. On Ozarkedge, I’ve found the scent is more apparent after the bloom. It’s not very noticeable on each flower, instead, when I walk past a stand of spent flowers or even seed pods, I catch the scent on any slight breeze. It’s a lovely reminder of the beautiful flowers which have given way to developing seeds. Sweet black-eyed Susan smells sweetest after the blooms fade
Description- Sweet black-eyed Susan is usually about 4-5 ft tall. She usually has one main stem that branches multiple times toward the top of the plant. Each upper stem terminates in a single flower. There are many flowers per plant. Single stems branch many times to provide clusters of flowers
The leaves appear alternately on petioles along the stem. The upper leaves may lack petioles. The leaves are rough to the touch with the underside of each being hairy (hence the term submentosa). They are usually 3 lobed on the lower stem and single in the upper portion of the plant, although there is overlap. The middle lobe is larger than the 2 side lobes and has a lanceolate shape. There are teeth along the edges. Lower leaves have 3 to 5 lobes Upper leaves are usually single lobed
Each flower is a composite of both disk and ray flowers. Each yellow petal is a ray flower (infertile). The many disk flowers make up the brown center. Each disk floret (fertile) will produce a seed. The ray flowers vary in width from plant to plant, some being wide and lush looking while others are narrow, somewhat like those of the pale purple coneflower. I can’t say that I prefer one look over the other. Both are simply beautiful. Wide ray flowers (petals) Narrow ray flowers (petals) A few of the disk flowersin the brown center are blooming Brown seedpods ensure generations of flowers to come
Bloom Time- On Ozarkedge, Rudbeckia submentosa blooms from early to mid August (depending on rainfall) to frost (mid October). Buds ready to burst into bloom July 17th Peak flowering in early September
Habitat- Rudbeckia submentosa is typically found at the woodland edge in a mesic habitat. I’ve read that this plant can be cultivated to take full sun but I haven’t observed her growing in that habitat naturally on Ozarkedge. I expect she could be cultivated to grow in full sun as long as there is ample water. I’ve noticed in years of low rainfall, the plants may wilt and drop some flower buds. Rudbeckia submentosa in mesic conditions at the woodland edge
What’s Growing Nearby?- Rudbeckia hirta has lots of friends at the moist woodland edge. Some of the flowers I find blooming nearby on Ozarkedge are shown below. Lobelia siphilitica surrounded by Rudbeckia submentosa
Endangered List- USDA lists Rudbeckia submentosa is listed as Endangered in Kentucky, Probably Extirpated in Michigan and Threatened in Tennessee. You can review the latest status on its USDA plant profile page here.
There is even greater cause for concern when one reviews the conservation status on NatureServe. This beautiful native is Presumed Extirpated in Michigan, Critically Imperiled in Kentucky, Mississippi and Texas, Imperiled in Tennessee and Vulnerable in Iowa. The 9 other states completing its native range are either Not Ranked or Under Review.
Interesting Tidbits- Take a look at the petals below and you will see that Rudbeckia submentosa is a favorite of many insects and caterpillars. It can be a host plant for the caterpillars of several butteflies and moths- including the Silvery Checkerspot butterfly. Bees are the most important pollinators.