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GREENBRIER: We're not privy to all the inside jokes among botanists, but we do know of some that are tongue-in-cheek and others that are even a little cruel. Like giving Common Ragweed the genus name of Ambrosia--the ancient Greeks' "food of the gods"--even though this noxious plant is a principal cause of autumn hay fever among allergy sufferers.
All text & photos © Hilton Pond Center To be honest the genus name Smilax has nothing to do with smiling; one interpretation is the word was originally derived from a Greek word for "poison," even though Greenbrier berries apparently are non-toxic. In fact, rhizomes (food-storing roots) from some Greenbrier species are used by herbalists to treat various skin diseases and gout and to reduce flatulence.
All text & photos © Hilton Pond Center Greenbrier's common name comes from the fact that its twining stems are typically all green, from ground level to tip even in old, established vines. (An alternative common name of Catbrier is bestowed for similarly obvious reasons.) However, not all varieties of Smilax look alike. There are about 14 species in the Carolinas and 300 or so worldwide--including herbaceous vines or short shrubs lacking spines; the killer kinds are semi-woody and heavily armed as illustrated above, but even some of the evergreen types are spineless. To clarify--or further confuse--all true Greenbriers are Smilax species, but not all Smilax species are Greenbriers.
All text & photos © Hilton Pond Center Greenbriers (and all species of Smilax) do have one thing in common: Their foliage has prominent reticulate veins as shown by a backlit leaf (above) of Roundleaf Greenbrier, Smilax rotundifolia. Such vein structure is more typical of the dicots--plants such as beans and oak trees with two seed haves and two cotyledon leaves--but Greenbriers are actually single-cotyledon monocots and are more closely related to corn and grasses. In fact, Greenbrier's closest relatives are Asparagus, Trilliums, Yucca, and Onions--all members of the Liliales (Lily Family).
All text & photos © Hilton Pond Center Even though all Greenbriers have reticulate-veined foliage, the configuration of the leaf blade varies among species. In general, leaves are heart-shaped, but they can be oval and laurel-shaped or even bearing basal lobes (above) as in Fringed Greenbrier, Smilax bona-nox. (Note #1: Some leaves of this particular species are heart-shaped and unlobed, while others bear less-pronounced lobes. Note #2: By this time of year--early November--it becomes difficult to find a Greenbrier leaf that has not been browsed by a caterpillar or some other creature. The one above shows several areas with herbivore damage.)
All text & photos © Hilton Pond Center Two other characters that vary among Greenbrier species are leaf margin and overall color. Most Greenbriers have leaf edges that are smooth (below), but some--such as the two just above--have occasional tiny, stiff bristles.
All text & photos © Hilton Pond Center And although Greenbriers typically have uniformly dark green leaves, species such as the two above show some degree of light spotting or variegation. Also note in the Greenbrier just above that its spines are tinier than those on some of the stouter species, but we know from experience they're just as sharp. (Ouch! again.)
All text & photos © Hilton Pond Center In the Carolinas most Greenbriers blossom in late April or early May, producing dangling umbels of quarter-inch greenish flowers (above) that are often overlooked. Pollination is likely by flies and native bees and perhaps small butterflies. (Several Smilax species have nauseatingly odorous blossoms and are called Carrion Flowers; as might be expected, they are pollinated by Carrion Flies.) Curiously, Greenbrier vines are dioecious--having male and female inflorescence on separate plants--so some vines may bear staminate flowers that never produce fruit.
If you miss seeing Greenbrier flowers in spring, come autumn you can tell whether your vines are male or female by looking for berry clusters silhouetted against blue sky. Incidentally, the photo above illustrates a characteristic found in most (but not all) woody Greenbriers: Their stems branch off at odd, sharp angles--which may help new stems find a place of attachment needed by this relatively flimsy vine unable to support itself.
All text & photos © Hilton Pond Center The structures by which a Greenbrier vine does acquire elevation are called tendrils, modified stems that are initially green and delicate but that turn brown as they harden their grip on some sort of external support. The tendrils are thigmotropic (sensitive to touch) such that tendril cells that come in contact with a solid object grow toward that object in the twining configuration shown above.  Ripened Greenbrier berries can be blue, black, or red, but the ones we found this week at Hilton Pond Center were blue-black, with a waxy white coating (above) that rubbed off easily. These rubbery quarter-inch fruits--consisting mostly of one to three seeds covered by not much nutritional pulp--are nonetheless eaten by a wide assortment of mammals (e.g., squirrels, rabbits, Black Bear, and Virginia Opossums) and birds (especially Northern Mockingbird, Gray Catbird, Cedar Waxwing, and Hermit Thrush). In Florida, Greenbrier fruit reportedly is consumed in great quantities by Fish Crows. (We should also mention that in some locales Greenbrier vines themselves are important winter browse for White-tailed Deer, while new leaves, shoots, and tendrils are salad favorites among wild food enthusiasts.)
All text & photos © Hilton Pond Center After those blue-black Greenbrier berries are eaten by a bird or mammal, their seeds (above)--each about the size, color, and shape of a Ladybird Beetle--pass through undigested and are deposited in a tidy little pile of scat that provides natural fertilizer when during germination the following spring. Each seed pops up as a monocotyledonous sprout that sooner or later sends out tendrils and develops those needle-sharp thorns that are the bane of field naturalists. Left unbrowsed and unpruned, a single Greenbrier vine can propagate into a nearly impenetrable thicket that provides shelter for organisms small enough to squeeze between its prickly stems. Such thoughts bring to mind an alternate explanation for how Greenbriers--i.e., Smilax--got their scientific name, to wit: According to Greek myth, Krokus was a mortal man who--due to the gods' restrictions on such relationships--suffered from love unfulfilled for Smilax, a woodland nymph. As punishment the man suffered the not entirely unpleasant fate of being turned into a beautiful flower--a Crocus, no doubt--but the wayward nymph was transformed into a less-attractive brambly vine. This story makes us smile, but when our ankles are pricked by Greenbrier--Smilax--it's NEVER something we can smile about. All text & photos © Hilton Pond Center If you have a Twitter account and liked this page, you can Follow us on Twitter: @hiltonpond
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And then there's Touch-Me-Not--that hummingbird flower that instantly scatters seeds when one bumps its pod--which a word-playing plant taxonomist christened as Impatiens. We thought about such things this week when we were walking off-trail through the woods around Hilton Pond Center and had to stop abruptly as a tough green vine seemingly leapt from the leaf litter to attack our ankles. It was Greenbrier, whose sharp straight thorns (below)--the floral equivalent of barbed wire--can lacerate one's lower extremities (and more) in an instant. We appreciate Greenbrier as a native plant (and we cherish our memories of The Greenbrier Resort in West Virginia, above right), but we don't like the pain Greenbriers can induce, and when they puncture our skin we certainly do not smile--even though Greenbrier's unfunny scientific epithet is . . . Smilax.
Sarsaparilla, also made from Greenbrier root juice, was historically guzzled down by amorous sailors (and Old West cowboys in particular) to treat social diseases. One source even says Greenbrier root "is believed to increase testosterone and progesterone levels in the body, as well as excite the passions, making men more virile and women more sensuous," so it's a wonder there's any left on the planet! We have to confess Greenbrier vines have indeed made our blood flow faster--but only when it oozed out this week from those jagged holes their thorns made in our ankles. Ouch!
