The words “subterranean termites” are enough to strike fear in the heart of any homeowner. Equipped with a cast iron stomach that digests cellulose materials, these insects can chew their way through dense wood, layers of paint, concrete and brick.
Termites have been part of the earth’s recycling system for a long time. A fossil termite dated to approximately 200 million years ago attests to the adaptability of this unwelcome guest. Two hundred years ago, termites invaded a stack of oak wood timbers being seasoned in a shipyard in France. One of Napoleon’s best warships was scrapped because its timber was riddled with termite tunnels.
The genus Reticulitermes is the principle termite pest in all areas of the Northern hemisphere, including Canada, Mexico, Europe, the Middle East, Northern Africa, India, Southern Russia, Korea, Japan, China and the United States. Their unique distribution provides an insight into the nature of these insects and their special adaptation for tolerating or evading cold weather while exploiting patterns of surface wood.
What a Family Profile!
The Nose Termite, or “Snouted Termite,” is an eastern subterranean termite which resides chiefly in the U.S. east coast. It has the dubious distinction of having a characteristic snout and being the most destructive pest in North America. New evidence of invasions in Manitoba and Alberta, as well as Ontario and British Columbia, are alerting Canadian homeowners to the new foraging range.
Of some 30 or so insect orders, termites are the only one in which all species are categorized as highly social. There are four castes in a colony: the reproductives and the winged ones (alate), the pearly-white blind workers; the large-headed soldiers with enlarged orange head capsules and strong biting jaws; and the nymphs. Each caste has a specific function in the colony.
“Termite, Retiulitermes flauipes. Upper panel: soldies above worker. Lower group: left, winged adult; top center, nymph; bottom center, king; right, queen”
As a highly developed social structure, termites cannot survive alone. The queen lays the eggs. She mates with the king, and the king fertilizes the eggs. Soldiers protect the royal cell of the king and queen. Workers build the mound, clean the cell and the queen, and feed the baby termites, which are called nymphs. A queen can lay about ten million eggs in her live span of 15 to 25 years.
A large number of winged termites, called alates, develop every year in a mature termite colony. The alates are the adult offspring of the colony and develop from the nymphal line. It takes about 2 1/2 years to reach this stage. A colony will produce about 20-40% nymphs, although not all nymphs reach the alates stage at the same time. Alates emerge as a group to seek mates and begin new colonies. This mass flight is an important food source for predators.
Nose termites build subterranean shelter tubes of soil material mixed with their saliva and fecal matter. These shelter tubes act as runways to get to the wooden parts of the building where the accomplished workers will begin their endless chewing of wood. Nose termites have flagellated protozoa in their gut, which makes it possible to eat and digest the cellulose. They also have other tiny animals living in their stomach called flagellates. When nose termites are placed under boiling temperature (100 Celsius) or increased oxygen, all the flagellated protozoa and other tiny animals vanish because they cannot take the pressure. Hence, nose termites cannot digest cellulose.
THE BALANCE OF THE PLANET
Eradication subterranean termites in North America does not seem possible. It is wise to seek the assistance of a professional pest control expert if tunnels are sighted near your home or a mass flight brings alates to your doorstep. But though the Reticulitermes wreck significant destruction on the human habitat, they also contribute to the recycling of wood fibers to soil. Ironically, wood and dry plant matter is the most abundant category of primary production on earth. Termites are the primary group of insects adapted to feed on this non-nutritive matter. They are also an important food source to birds and other predators that wait for their timed mass alate flight. They also provide food for more amphibians, reptiles, birds and ground-foraging mammals than any other group of insects.
The Smithsonian’s National Museum of Natural History has a large collection of termites, which include the nose termites. Stop by some time and meet this notorious insect. At least this introduction will not strike you with dread… Reticulitermes flavipes will be under glass.