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CAROLINA JESSAMINE:
SOUTH CAROLINA'S STATE FLOWER

Come April, Piedmont roadsides--or at least those that haven't been trimmed too heavily by overzealous maintenance crews--put on a show of color that brightens spring days for appreciative travelers. White tiers of Flowering Dogwoods fill the understory as far into the woods as the eye can see, and native Pinxter-flower azaleas bring a touch of color to semi-shady spots. Slow-moving commuters may spy wild strawberries and Johnny-jump-up violets blooming low along the asphalt shoulder, but even speedy drivers will find it hard to miss occasional clusters of bright yellow blossoms that adorn roadside shrubs and trees. Such inflorescence isn't from the trees themselves but is produced by a perennial vine that is South Carolina's official state flower--the Carolina Jessamine. Only a few of these plants grow at Hilton Pond Center, but those we have are as showy as one could want in a flowering plant.

All text & photos © Hilton Pond Center

Carolina Jessamine, Gelsemium sempervirens, was adopted as South Carolina's flower 'way back in 1924--long before legislatures began arguing over what should be a state's official beverage (in South Carolina, it's milk) or dance (the Shag) or Opera (Porgy & Bess). We concur that Carolina Jessamine was a splendid choice for the state's flower, and--like the official tree (Sabal Palmetto) and bird (Carolina Wren)--it's a symbol South Carolina doesn't have to share with any other state. (By comparison, three states have designated the dogwood as the official tree and/or flower, and no less than SEVEN lay claim to the Northern Cardinal as THEIR state bird.)

Carolina Jessamine was selected as the official flower by South Carolina's General Assembly because "it is indigenous to every nook and corner of the State; it is the first premonitor of coming Spring; its fragrance greets us first in the woodland and its delicate flower suggests the pureness of gold; and its perpetual return out of the dead of Winter suggests the lesson of constancy in, loyalty to, and patriotism in the service of the State." Despite all this flowery legislative language, Carolina Jessamine doesn't grow just within the Palmetto State. It is found from southeastern Virginia to Florida and west to Texas, but in our experience achieves its finest displays throughout South Carolina's Coastal Plain, where it literally blankets large shrubs or snakes its way high into sun-drenched pines and hardwood trees (below). In the absence of vertical support, it even forms its own thickets, rambling over open ground and growing into a tangle a foot or so deep.

A similar-looking species--Rankin's Yellow Jessamine, G. rankinii--is found in lowcountry swamps of the Carolinas, Georgia, and Florida; however, it lacks one of Carolina Jessamine's finest features: a sweet, dreamy, unmistakable fragrance. We regret we can't provide a "scratch-and-sniff" component on the Hilton Pond Web site, for the odor of Carolina Jessamine is one that should be shared with those who've never had an encounter. It's impossible to describe the scent in words, but various folks have referred to it as "heady," "overpowering," "intoxicating," and even "narcotic." The latter description may have arisen because Carolina Jessamine is laden with strychnine-related alkaloids, some of which can be quite toxic if ingested. In fact, virtually every on-line or print reference to Carolina Jessamine warns that all parts of the plant are poisonous if eaten, and that the sap itself can cause dermatitis. Native Americans used jessamine extract to reduce cramping and deaden pain or as a blood purifier, but some texts warn that swallowing even one flower can cause death by paralysis. (Hint: Keep this plant out of your mouth.)

Alkaloids are even found in the nectar of Carolina Jessamine--which seems counterproductive if you're trying to attract pollinators; why should a plant with plentiful, showy, and odoriferous flowers produce nectar that could be toxic? It may be the nectar isn't really all that poisonous to some native invertebrates--Bumblebees and a few butterflies apparently do visit Yellow Jessamine--but nectar with a strong alkaloid taste might repel herbivores that would eat the blossom before a seed could be produced. Curiously, we've never seen Ruby-throated Hummingbirds dining on Yellow Jessamine, even though when the hummers arrive in early April the vine blooms more prolifically than almost any other native species; perhaps the nectar is just too bitter for the average ruby-throat. However, hummer bander Nancy Newfield reports that wintering Rufous Hummingbirds frequent early-blooming jessamine in Louisiana during January and February, when they choose the yellow flowers over her traps containing sugar water feeders.

The 2-inch-long flower of Carolina Jessamine starts out as a torch-shaped bud that opens into a trumpet-shaped flower with five petals fused along half their length (see top photos). The stamens are short and hidden near the bottom of the tube, but the sticky tip of the long, whitish stigma lies just within the flower's mouth. A day or two after the flower opens, it withers and drops to the ground, leaving behind the bulbous green ovary and the delicate stigma (above right). Assuming pollination occurred, the ovary will mature and eventually produce a flattened seed pod about half an inch long (above left). As the fruits ripen, the pod dries and opens, releasing many dull brown seeds.

Across most of its range, Carolina Jessamine is non-deciduous and can be identified even in winter by twisted, red stems and green-and-purple pointed leaves (below). For now, as the profusion of yellow blossoms and tantalizing scent become a memory, jessamine's foliage will provide energy to send its vine ever higher into trees at Hilton Pond Center. We'll be keeping an eye on all those leaves and stems 'til next April, when we'll once again wait for the sight and smell of Yellow Jessamine to tell us our hummingbirds are on their way--even if they don't drink the nectar.

All text & photos © Hilton Pond Center
Seed pod photo courtesy www.nobleplants.com

POSTSCRIPT: Following our posting of this photo essay, we heard from Dr. Rebecca Irwin, an ecologist at the University of Georgia, that main jessamine pollinators around Athens GA are Bumble Bees (Bombus bimaculatus), Eastern Tiger Swallowtail butterflies (Papilio glaucus), European Honey Bees (Apis mellifera), and small native species such as Blue Orchard Bees (Osmia lignaria) and Blueberry Bees (Habropoda laboriosa). She also reports that Carpenter Bees (Xylocapa virginica), typically chew holes through the sides of flowers to steal nectar without pollinating, and that she hasn't ever observed hummingbirds feeding on Yellow Jessamine blossoms. Dr. Irwin and Dr. Lynn Adler of Virginia Tech are collaborating on lab tests to determine if jessamine nectar is indeed bee-toxic.

Dr. Lissa Leege of Georgia Southern University reports an interesting variation in the structure of Yellow Jessamine flowers: "You have described (above) the long morph--with long styles and short stamens-- there is also a short morph with the reverse arrangement. These flowers are produced on genetically different individuals; i.e., you would never find both short and long morph flowers on the same plant. Only pollen from opposite morphs will allow for successful fertilization to produce seeds."

Other insects that were reported feeding on Carolina Jessamine include sphinx moths (from Norris Muth, University of Tennessee) and Cloudless Sulphur butterflies, Phoebis sennae (Nathan Dias, Charleston SC).

NOTE: Be sure to scroll down for an account of all birds banded or recaptured during the week, as well as some other interesting nature notes.

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