I was recently in coastal North Carolina with Extension colleagues from around the country. In addition to attending presentations on natural resource programming, we attended field tours built into the meeting. I joined a group visiting a large parcel of longleaf pine, and we were treated to multiple sightings of red-cockaded woodpeckers. These are a threatened species but quite active in this forest.
But my biggest draw to participating in this trip was the promise of seeing carnivorous species. We are lucky to have several healthy stands of pitcher plants, sundews, and butterworts in northwest Florida. But we don’t have Venus flytraps (Dionaea muscipula)! Made famous by The Little Shop of Horrors play and movie, these fascinating little plants capture the imagination. Instead of tubular pitchers or sticky leaf traps, the Venus flytrap has a hair-trigger mechanism that encloses insects into its paired leaves and sealed within its “teeth.” We are used to imagining plants as immobile, so the idea of a plant that can “bite” really disrupts our understanding of the world. Those intimidating spikes at the margin of the leaves are more like sensitive tendrils. Attracted to the reddish insides of the leaf, insects crawl along the edge, touching bristles and setting off a mechanism that creates rare movement in a plant. The technical term for one of those spiky tendrils is a “trichome.” When two or more trichomes are triggered in quick succession by movement, a metabolic process called thigmonasty begins. The movement of nutrients and water within the plant cause changes in osmotic pressure, resulting in reduced rigidity of the plant’s cell walls and the leaves closing. A similar phenomenon known as thigmotropy explains how vines curl towards a stimulus and wind around them. “Thigma” is Greek for “touch,” “tropy” means “response or turning,” while “nast” refers to non-directional movement.
Venus flytraps grow in the same type of habitat as pitcher plants—soggy bogs with mucky, nutrient-poor soil. They can handle a little more shade and cold, and grow along the edges of forested wetlands called pocosins. They’re native only to the wetlands of coastal North and South Carolina, and only one species of its type exists. The vast majority (75%!) of the wild plants are located within a Nature Conservancy property, North Carolina game lands (where I saw them), and on buffer property around Camp LeJeune.
While the plants are quite small and the modified “flytrap” leaves grow close to the ground, we identified them easily by the white blooms growing upright about a foot off the ground. This physical distance helps prevent predation of the same insects plants rely upon to pollinate them.
Venus flytraps are grown commercially and are available for sale at some nurseries, but they require particular care. Only use rainwater or distilled water to water them, and refrain from deliberately triggering the closing mechanism of the leaves. It takes a significant amount of energy for the plants to close, and overdoing it could stress and kill the plants. If you have a chance to see the plants in the wild, step carefully–they are threatened by habitat loss and wild poaching.
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