The Formosan subterranean termite species has become one of the most destructive termite species in the US since the invasive pests were introduced into the country nearly six decades ago. While the native eastern subterranean termite remains the most economically damaging termite species in the US, invasive Formosans displaced native termites long ago as the most destructive termite pests in Louisiana. Unlike native termite species, the Formosan subterranean termite infests and feeds on a variety of living tree species. This is a problem in New Orleans where live oak trees have long provided the urban landscape with aesthetic appeal. Thousands of live oaks line the streets in New Orleans, some of which are older than the city. A particularly large and easy-to-climb live oak tree officially named the “Étienne de Boray Oak” is a beloved live oak specimen located in New Orleans Audubon Park. This tree, often called the “tree of life,” is believed to be free of termite damage, but the same cannot be said for many other live oak trees in the city.

For decades, Formosan subterranean termites had maintained infestations within countless live oaks and other tree species in New Orleans, but this damage did not become apparent until hurricane winds caused a large number of heavily infested trees to fall over due to being weakened by heavy and long lasting termite infestations. Incidents involving infested neighborhood trees falling onto cars and houses proved that Formosan termite infestations can be hazardous in ways that pest control professionals would never have suspected. By the time 2000 rolled around, the state of Louisiana undertook efforts to save live oaks from termite damage. Infested trees were treated with insecticide, which worked to both prevent infestations and eradicate existing ones. However, this program relied on remedial termite control methods rather than preventative methods, prompting public demands for proactive measures to protect trees from termites. Hurricane Katrina took down hundreds of infested trees in 2005, prompting local leaders to initiate a tree planting program. Nearly 350 live oaks were planted in areas where the trees once stood. Today, New Orleans’ live oaks appear healthier than they have been in decades, but a recent study found that at least 15 percent (112 trees) of live oaks on St. Charles Ave. have sustained recent termite damage, indicating that more needs to be done to protect the city’s trees. One method of preventing infestations involves the planting termite-repellent vegetation around the trees. Local leaders in New Orleans are now formulating a new plan that relies largely on preventative termite control methods to protect the city’s iconic live oaks.

Have you ever found a tree that was badly damaged by termites?