Above: Eastern Subterranean Termite Reticulitermes flavipes

Worker	Solider	Termite Colony	Damage to wood

Identification

The eastern subterranean termite, Reticulitermes flavipes nests in the soil and feeds on wood buried in or near the soil. This termite species prefers moist wood and is the common termite of New England. Worker termites are small white insects that avoid light and build mud tubes to reach wood above ground. The mud tubes are made of soil and saliva and are about the diameter of a pencil. Large termite swarms occur in the spring when black, winged reproductive males and females leave the nest to mate and disperse. The size of the underground colony can reach millions of workers and several buildings can be attacked by a single large colony.

Workers are pale white, small, soft bodied insects less than ¼ inches in length. The soldiers are fewer in number, larger and with a large head and mandibles. Soldier termites are white with a dark yellow head. The male and female reproductives are black with four pairs of equal size clear wings. The wings drop off immediately after mating and they may pile up near windows and other sources of light.

Termite damage to wood can be recognized because there are small fecal pellets of digested wood along with soil particles within the galleries. Galleries are typically located in wood close to or touching the ground or wood wet with excessive moisture from a leak or other water source.

Biology

Winged males and females swarm (fly) during late March and early to late April. These reproductives then mate, drop to the ground and immediately loose their wings. These mated pairs of male and female then together excavate into the soil and begin a new nest. A termite can feed on paper, buried wood, bark mulch, dead roots of trees, and of course wood frame timber in houses.

Termites normally damage wood slowly over time. There is no need to panic, when an infestation is found, take your time to understand the sources of moisture and the location and amount of damage.

Control

Infestations are often reported because of reproductive swarms coming up inside the building. The dark reproductive winged forms fly in large numbers every spring. Winged termites usually are trapped inside a window as they are attracted to light. There may be no damage to the structure, the nest may be in buried wood below the building and the reproductives are entering the building through cracks in the foundation. Sealing these cracks is all that is required to solve this type of infestation. This is especially true when the building foundation is not made of wood.

Traditional control strategies in the past required an insecticide to be applied to the soil as a barrier against termite invasion. This approach results in large quantities of insecticides being introduced under the structure using drills and trenches. However, a new technology using termite baits shows great promise. Wood pieces impregnated with a toxicant are set out to survey and control for termite foragers. Termites feed on the bait and return to the nest to share the toxicant with other nest mates, their young and the king and queen.

I suggest monitoring a building over time to verify that the termite damage in evidence is old and there are no live termites. Monitoring for termites can take the form of watching for any live activity during a renovation, reports of swarming termites, and installing wooden monitor stakes around the outside perimeter of the building to detect termite feeding activity.

Stabilizing Damage to Support Beams

There are two boric acid products labeled for wood treatment for the control of termites and wood boring beetles. Both can be applied by professional pest control operators as a spot treatment to protect and stabilize wood against future attack. Only exposed sections of wood beams can be treated, limiting coverage.

Evaluation of Extent of Damage and Prevention

Careful examination and probing of wood will help determine the extent of the termite infestation and the amount of wood damage. Conditions that contribute to increased wood moisture should be corrected as part of the renovation. Storm water should be directed away from the foundation and vapor barriers used whenever possible.