The giant stinging tree, often called Gympie-Gympie, is known for its potent sting. It belongs to the Dendrocnide genus, a group of plants infamous for their stinging capabilities. Its sting causes intensely painful and long-lasting effects upon contact.
Identifying the Plant and Its Habitat
The giant stinging tree, Dendrocnide moroides, grows as a straggly perennial shrub, reaching up to 10 meters (33 feet) in height. Its leaves are large, broadly oval or heart-shaped, and pale green, measuring approximately 12–22 cm (4.5–8.5 inches) long and 11–18 cm (4.5–7 inches) wide. These leaves have saw-toothed edges and a pointed tip, appearing furry due to a dense covering of fine stinging hairs, which are also present on its stems and fruits.
This plant is primarily found in rainforest areas of Australia and Malaysia, particularly common in Queensland, Australia, from Gympie in the south to the Cape York Peninsula. It thrives in disturbed areas and along rainforest edges, often found in upland regions such as the Atherton Tablelands. Smaller plants are sometimes called “ankle biters” due to their low stature.
Understanding the Sting and Its Impact
The giant stinging tree stings through hollow, silica-tipped hairs, known as trichomes. When these hairs penetrate the skin, they break off, releasing a complex mixture of toxins, including neurotoxin miniproteins called ‘gympietides’. These gympietides are structurally similar to venoms found in spiders and cone snails, targeting the same pain receptors in the body.
Upon contact, a victim experiences an immediate burning and stinging sensation that intensifies over the next 20 to 30 minutes. This pain can persist for hours, days, or even months, making sleep difficult. The affected area develops small red spots that merge into a red, swollen mass, and the pain may spread to other parts of the body. The long-lasting pain is thought to be caused by gympietides permanently altering sodium channels in sensory neurons, rather than just the physical presence of the hairs.
Immediate Care and Prevention
If contact occurs with a giant stinging tree, avoid rubbing the affected area, as this can break off more stinging hairs and worsen the pain. The primary goal is to remove the stinging hairs from the skin. A common method involves carefully applying hair removal wax or adhesive tape to the affected skin and then swiftly pulling it off to extract the embedded trichomes.
After removing the hairs, applying heat or cold packs may help alleviate the pain, though effectiveness can vary. The injured area can remain intermittently sensitive for extended periods. To prevent contact, individuals in known habitats should wear protective clothing, including long sleeves, pants, and gloves. Staying on marked trails and identifying the plant from a distance are also important precautions.