Last updated Dec. 18, 2004
Venus flytraps: An Endangered Species
Venus Flytraps (Dionaea muscipula) with their flowers
© 2004 Claude W. Rankin and Southern Connections Inc.
Venus flytraps are an endangered species and native only to the boggy areas of southeastern North Carolina and eastern South Carolina.
They have not thrived in Florida and New Jersey, where they were introduced.Their clamshell traps are unique and born or necessity. Their native soils are poor in several essential plant nutrients, especially nitrogen.
Insects are their source of essential nitrogen. A study published in the Journal of Experimental Botany found that Dionaea muscipula gets as much as 75 percent of its nitrogen from the capture of insects.
Dionaea muscipula must grow traps big enough to capture large insects before they can flower and produce seeds.
They bloom in May and June, producing the white, five-petaled blossoms you see in the photograph.
Their fully open flowers are about three quarters of an inch across.
The flowers mature into ovoid fruit capsules.
Six to eight weeks the plants flower, their fruits open to release tiny, pear-shaped, black seeds.
Prey-attracting nectar is secreted inside the lips of the trap. When a feeding insect touches one of the trigger hairs, the trap closes enough to trap its prey in two to six seconds. The ominous spines form a cage, and the trap may continue to close for more than an hour. When the trap reopens several days later, only the insect's exoskeleton remains.
© 2004 Claude W. Rankin and Southern Connections Inc.
Unsurprisingly, Venus flytraps are dormant during the fall and winter, when insects are not readily available.
Legally collected or propagated Venus flytraps are widely sold.
Collection for that novelty plant trade was at one time the primary cause of their endangerment. In part because North Carolina law regarding their collection and sale is well-enforced, that may no longer be the case.
Forestry development and fire suppression have become the primary causes of their decline.
Periodic, lightening-ignited fires were a natural aspect of the world in which Dionaea muscipula evolved. The fires suppressed grasses and shrubs with which Dionaea muscipula is poorly equipped to compete.
Closed trap digesting prey. Traps shrivel up and fall off after capturing a few insects.
© 2004 Claude W. Rankin and Southern Connections Inc.
- Superdivision: Spermatophyta -- Seed plants (seed plants)
- Division: Magnoliophyta (flowering plants)
- Class: Magnoliopsida (primitive flowering plants)
- Subclass: Dilleniidae
- Order: Nepenthales
- Family: Droseraceae (Sundew family)
- Genus: Dionaea Ellis
- Species: Dionaea muscipula Ellis
Taxonomic Classification
References
The North Carolina Native Plant Society's Rare Plant Initiative
Atlas of Florida Vascular Plants Venus flytraps page
US Department of Agriculture Plants Database
Fairchild Tropical Garden Virtual Herbarium
Journal of Experimental Botany Venus flytraps article
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