Few cities are as closely tied to a termite as New Orleans. The Formosan subterranean termite arrived in Louisiana in the middle of the twentieth century, likely in shipments after World War II, and it took hold quickly in a city with wooden buildings, endless moisture and a port. Today these termites are part of the urban landscape, and their colonies can be far larger than those of native species.
Formosan versus native termites
Louisiana has two main subterranean threats. The native eastern subterranean termite builds moderate colonies in soil. The Formosan termite forms massive colonies, sometimes with millions of members, and it can build aerial nests inside walls and roofs if it finds a steady water leak, which means it does not always need contact with the ground. Formosans consume wood faster and swarm in large numbers on warm evenings in late spring, flocking to lights. Drywood termites occur in the region as well, although they are less central here.
Why old New Orleans buildings are so exposed
Historic cypress and longleaf pine framing in the French Quarter, Marigny, Treme, Garden District and Uptown has been feeding termites for generations. Raised pier foundations leave a damp, shadowy space beneath the floors. Wooden balconies, galleries, porch columns and shutters stay wet from humidity and storms. Roof leaks and clogged gutters in older buildings give Formosan colonies the moisture they need to nest above ground. Even masonry buildings contain wood joists, doors and trim. Post-storm damage with wet insulation and soaked timber produces additional vulnerability.
Signs of activity
- Swarms of winged insects around lights in May or June, often in the evening.
- Carton-like material, a papery brown mud, in cracks or in walls.
- Mud tubes on piers, foundation walls and under stairs.
- Wood that sounds hollow when tapped, or paint that bubbles.
- Doors and windows that jam, along with sagging floors.
Inspection and treatment
An inspector checks the crawl space or pier area, subfloor, attic, balconies and any plant beds touching the building. Treatment options include liquid soil treatment around the foundation, baiting systems, direct wood treatment, and in some cases dusting of active galleries. Because Formosan colonies can be large and may involve aerial nests, many providers use a combined approach and schedule regular inspections afterward. Moisture repair is part of the plan. Historic building owners should ask how work will protect original materials.
What owners should do
- Repair roof and plumbing leaks promptly and keep gutters clear.
- Remove wood debris, stumps and cardboard from crawl spaces and yards.
- Keep planting beds and mulch away from siding and sill plates.
- Maintain a contract for regular termite inspections.
- Schedule a termite check after any flood or major storm.
Buying or renovating in New Orleans
Anyone purchasing a house in New Orleans should expect termite history to come up in the inspection, and anyone renovating should expect to find some old damage when walls open. Ask the seller for past treatment records and bait station locations, and have the inspector examine porches, galleries and any additions, which are often built with untreated lumber. Repairs made without addressing active termites simply feed the colony new wood.
Getting connected
PestMinistry is a referral service rather than a termite company. Call (844) 725-1661 and we will connect you with an independent licensed provider in our network who works with Formosan termites in New Orleans, LA. Ask how they handle historic properties.
When do Formosan termites swarm?
Typically in late spring, often on warm, humid evenings after rain. They are attracted to light.
Can termites live in walls without touching the soil?
Formosans can, if they have a reliable moisture source such as a leak, which makes roof and plumbing maintenance vital.
Is my brick building safe?
Not entirely. Brick walls often contain wood framing, floors and doors that termites can reach.
Do I need ongoing service after treatment?
Because new colonies can arrive from neighboring properties, many owners keep up a renewal program with periodic inspections.