If you live in Mobile and you only know one species of termite, you probably know the wrong one. The eastern subterranean termite has been the textbook example in Alabama for as long as anyone has been writing textbooks. But for at least three decades, a different and far more destructive insect has been quietly working through Mobile County, Baldwin County, and the rest of the central Gulf Coast: the Formosan subterranean termite, Coptotermes formosanus.

Where it came from, and where it is now

Formosan termite is not native. It arrived in the United States on military cargo returning from the Pacific after World War II and was first recorded in Mobile County in the 1960s. From that beachhead it has moved north and west through the Mobile River corridor and into the western suburbs of West Mobile and Semmes. Auburn University Cooperative Extension surveillance has tracked the species moving roughly one mile per year.

Why this species is a different problem

A mature native subterranean colony might contain 30,000 to 250,000 workers. A mature Formosan colony contains millions. Formosan colonies build aerial ‘carton nests’ that hold their own moisture, which means they can survive in a second-story wall cavity or attic — without soil contact. That single trait makes traditional soil-perimeter treatments less effective than they would be against a native species.

What this means for your house

The wood-destroying-organism inspection — the NPMA-33 letter that almost every Mobile-area mortgage requires — is not a guarantee. It certifies what the inspector could see on the date of inspection. With Formosan termites hiding in aerial cavities, an absent finding is not the same as an absent infestation.

Homeowner insurance generally does not cover termite damage. The protection is preventative: a real, current termite contract with a licensed operator, written for the species that is actually a threat in this region.

Alabama regulates pest control under the Alabama Department of Agriculture and Industries. The license category that authorizes termite work is WDC (Wood-Destroying Organisms). A handyman, a general pest-control technician without WDC, and a lawn-care provider are all unlicensed for this work.