Identifying and Detecting Termite Types
In South Florida and Fort Lauderdale, most species of drywood termites infest dry, sound wood—including structural lumber, dead limbs on trees, utility poles, decks, fences, lumber in storage, and furniture. From this infested wood, winged reproductives periodically swarm to infest additional nearby wood. Drywood termites are prevalent throughout Florida, including cooler areas. Nests of most species remain entirely above ground and do not connect to the soil.
Similar to dampwood termites, feeding by drywood termites can cut across the grain of wood leaving a characteristic pattern of chambers and tunnels, some of which are filled with fecal pellets. Drywood termites often expel their fecal pellets through surface openings and they can accumulate on horizontal surfaces below the openings. These fecal pellets, which are distinctive in appearance with six longitudinal flattened sides, may be the first clue to their presence.
Dampwood termites are common throughout South Florida; due to high moisture requirements, they are most often found in cool, humid areas along water areas. They typically infest decayed wood that remains moist either through contact with the soil or exposure to a water leak. Dampwood termites create large, open galleries within the wood where they live and feed. Their presence is significant as an indicator of a moisture problem or wood decay in wooden structures.
Subterranean termites are common throughout Florida and can be found infesting fallen trees, stumps, or other dead wood in contact with the soil in the woods, landscape, or structural lumber in our houses.
The most common subterranean termites, formosan, can be encountered in nearly all regions of the state. The species of Formosan termites are the most destructive termites found in Florida. They are small in size compared to dampwood and drywood termites, but mature colonies can contain hundreds of thousands of individuals.
Reproductive winged forms of subterranean termites are dark brown to brownish-black with brownish-gray wings. On warm, sunny days following fall or spring rains, swarms of reproductives may be seen emerging en masse from their underground nests. Soldiers are wingless with light caramel-colored bodies and long, narrow amber-colored heads with no eyes. Workers are slightly smaller than reproductives, wingless, and have a shorter head than soldiers; their color is similar to that of soldiers.
SIGNS OF SUBTERRANEAN TERMITE INFESTATION
Signs of a subterranean termite infestation include swarms of winged reproductives in the spring, summer, or fall, the presence of shelter tubes, and evidence of tunneling in wood and foundations. Shelter tubes (sometimes called mud tubes) are the most commonly seen evidence of a subterranean termite infestation. These earth-hardened tubes are made by workers using saliva mixed with soil and bits of wood or even drywall. There are four types of tubes:
working tubes are constructed from the nest in the soil to wooden structures and they may travel up concrete or stone foundations;
exploratory and migratory tubes arise from the soil but do not connect to wood structures;
drop tubes extend from wooden structures back to the soil; and
swarm tubes for new and swarming reproductive kings and queens to emerge from and fly away during swarm season.
If you break termite tubes open, you may see live workers and soldiers running through the tubes. The darkening or blistering of structural wood members is another possible indication of an infestation; wood in damaged areas is typically thin at the surface and easily punctured with a knife or screwdriver. Finding live termites foraging within wood is a sure sign of an active infestation.
The excavations that termites make in wood are hollow, completely enclosed, more or less longitudinal cavities. Some species deposit light-brown excrement within cavities. Feeding in wood by subterranean termites generally follows the grain of wood; these species attack the softer springwood and leave the harder, less digestible summerwood. Many times this distinctive pattern of wood damage alone can be used to positively distinguish subterranean termite activity from that of other species.