HAMMOND, La. – The stinging caterpillars that will become buck moths are beginning to appear in south Louisiana and will be active through May.
LSU AgCenter forestry entomologist Tim Schowalter said the caterpillars are found in oak forests throughout the southeastern United States as far west as Texas.
“During years when they are abundant, often co-occurring with tussock moths and forest tent caterpillars, they can eat most foliage from oak trees, leaving trees looking sparsely foliated,” Schowalter said.
However, oaks are capable of producing additional foliage and typically show no symptoms of defoliation by midsummer.
When mature, the caterpillars descend to the ground to pupate.
“This is when people typically come in contact with the caterpillars,” Schowalter said. “People experience the painful sting of the caterpillars either by stepping on them on the ground or by brushing against them on walls or shrubs.”
The caterpillars are covered in hollow spines that are attached to a venom gland. The venom can cause symptoms ranging from itching and burning sensations to nausea.
In cities such as Baton Rouge or New Orleans where live oaks are common along city streets, the caterpillars can become a significant nuisance for people, Schowalter said.
First aid for stings involves the following steps:
– Place tape over the stung area and carefully peel it away to remove any spine tips.
– Take liquid Benadryl to alleviate any allergic reaction; if swelling or difficult breathing occurs, go immediately to an emergency room.
– Aspirin or other pain relievers can reduce pain.
– Meat tenderizer, calamine lotion, aloe or other favorite sting remedies can help reduce the duration of pain.
Adult moths will emerge during mid-December to mate and lay eggs. The moths are medium-sized, brown and white with orange legs and tips on their abdomens.
“They can be seen flitting erratically, especially around oak trees,” Schowalter said. “Their eggs are typically laid in spiral clusters on oak twigs.”