Termites and Ants

Termites

Each year, many households in Maryland become infested by a variety of wood destroying insects, the most notable being termites. If left unchecked they can cause serious structural damage to a home. In fact, in the United States, termites do more damage to homes annually than all reported fires, tornadoes, hurricanes and windstorms combined.

The termite species that is indigenous to Maryland is the Eastern Subterranean Termite (Reticulitermes flavipes). As its name implies, it lives beneath the soil. Termites, like ants and bees, are social insects and live in colonies. The termite colony is comprised of several castes including a queen, soldiers, winged reproductives (swarmers) and workers. The winged reproductives, or swarmers, are the form most commonly seen by homeowners. Ant colonies also release winged reproductives (flying ants). Many times termite infestations go unchecked when a homeowner mistakes termite swarmers for flying ants.

Characteristics

Body Part Termite Ant
Antennae
Resemble a string of beads
and are never elbowed.
Usually elbowed and
segments note similar in
shape.
Body
Uniform shape without
constriction between body
parts.
Constricted between thorax
and abdomen forming an
hour-glass "waist."
Wings
Both pairs of wings of
identical size. They are
cloudy with many fine,
conspicuous veins.
Hind wings are much smaller
than fore wings. They are
clear with few, dark,
conspicuous veins.

TERMITEANT 


While termite swarmers are a nuisance, they do not cause damage. Their sole function is to find a mate and begin a new colony. The "worker" caste makes up the bulk of the termite colony and is the only individual in the colony that forages for food and is directly responsible for causing damage to wood and cellulose containing materials. They have no eyes or wings and are soft-bodied, whitish in color and approximately 1/4 inch in length.

The soldiers also have no eyes or wings. They do, however, have enlarged jaws called mandibles which they use to defend the termite colony. They are otherwise similar in appearance to the workers of the colony, whitish in color but their head is enlarged and sometimes brown in color.

Termites are different from almost all other insects in that they can convert the cellulose in wood products back into sugar and utilize it as a food source. In nature, termites are beneficial as they help convert dead wood and other materials containing cellulose into humus. Some other types of insects, such as powderpost beetles and old house borers, eat wood but cannot convert the cellulose to sugar. They receive nourishment from the sugars and starch which the tree stored during its growth. Still other insects, such as carpenter ants and carpenter bees, get no food whatever from the wood but simply excavate holes and cavities in the wood to provide protective shelter.

TERMITE - SOLDIER 

TERMITE - WORKER 

Carpenter Ants

There are a number of ant species that infest homes and buildings. However, the carpenter ant is perhaps the only species that damage wood and are encountered in homes. They do not consume the wood but only build their nests within it. Their foods, similar to those of many other house-infesting ants, are found in kitchens, pantries and other areas where food is stored. Carpenter ants are the largest of the house-infesting ants. Workers within the colony range in size from about 3/16 to 5/8 inches in length. Color varies among species, although black seems to be predominant.

Carpenter ants, like termites, tend to prefer wood that is partially decayed by wood rot. However, they will also attack perfectly sound wood as well. They excavate wood members of buildings, especially when a cavity or enclosed space already exists. Often, these cavities are enlarged to the point that structural damage occurs, but more often the movement of foraging ants within a structure becomes a nuisance. Carpenter ants may travel or forage for distances of several hundred feet. They keep the inside of their excavations clean by discarding the litter of large wood particles (frass) out of the most convenient opening. The coarse frass, when discarded, can be an aid in locating the colony for control purposes.

Wood Boring Beetles

POWDER  POST BEETLE 

OLD HOUSE  BORER 

In addition to termites and carpenter ants, there are a number of other wood destroying insects that can attack wood members in structures. The two most notable are the old house borer beetle and the powder post beetle. Both of these beetles are found in Maryland. The Lyctid powder post beetle attacks only the sapwood of hardwoods with large pores, e.g., oak, hickory, ash, walnut, or pecan, and feeds on starch in the wood. Lyctids range from 1/8 to 1/4 inch in length and are reddish-brown to black in color. The presence of small piles of fine powder (frass) under the wood is the most obvious sign of infestation. The exit holes are round and vary from 1/32 to 1/16 inch in diameter. The larvae are tiny "C" shaped grub-like larvae that are found feeding in tunnels in the wood. Powder post beetles can reinfest the same piece of wood until it is reduced to a shell of frass with the consistency of face powder held in by a very thin veneer of surface wood with beetle exit holes.

The old house borers are members of a large beetle family called the long-horned beetles, named because of their long anntenae. The old house borers were imported from Europe in infested lumber. Unlike the powder post beetle, they attack only the sapwood of softwoods such as pine, spruce, fir and hemlock. The adults emerge in early summer, living for approximately 16 days, during which time the females lay approximately 150 to 200 eggs in cracks or crevices in the wood. The larvae that hatch bore into the wood and take up to ten years to complete their life cycle. The larvae cause the damage by feeding on the wood. The rasping and ticking of their feeding activity is often the first sign or indication of infestation that a homeowner may detect. When the adults emerge they create oval shaped holes in the surface of the wood that are approximately 1/4 inch in diameter. The galleries in the wood are filled with fine frass mixed with small pellets.

Carpenter Bees

CARPENTER BEE Carpenter bees are other wood destroying insects that can be found in Maryland. They are large bees that look very much like bumble bees. The major difference is that carpenter bees have a bare, shiny black abdomen whereas bumble bees have a hairy abdomen with some yellow markings. Male carpenter bees are agressive but harmless as they have no stinger. However, females can and will sting if they feel threatened.

Carpenter bees cause damage to wood when they bore holes to create a tunnel in which to raise their young. They prefer softwood such as pine, poplar, cedar and redwood for nesting. The holes they bore are quite distinctive in that they are approximately 1/2 inch in diameter and almost perfectly round.

Other Wood-Inhabiting Insects

There are several other species of insects that damage wood. However, these insects only infest dying or freshly cut trees or unseasoned wood. They do not infest wood that has been kiln dried or seasoned . The ambrosia beetles, bark beetles, horntails (wood wasps), and flat-headed borers fall into this group of wood-inhabiting insects. Control measures are not needed to prevent further damage since the wood was infested prior to milling. Evidence of infestations, such as holes or tunnels, resulting from these insects can be seen on the surface of milled lumber.

Ambrosia Beetles - These insects attack unseasoned softwood and hardwood logs. They produce small, 1/50 to 1/8 inch, circular holes. The bore holes do not contain frass, but are frequently stained blue, black or brown.

Bark Beetles - These insects tunnel at the point where the wood and bark meet and etch the surface of the wood contacting the bark. Beetles left under bark edges on lumber may survive for a year or more as the wood dries. They do not infest wood.

Horntails - These insects generally attack unseasoned softwoods and do not reinfest seasoned wood. They attack both sapwood and heartwood, producing a tunnel which is roughly C-shaped in the tree. Tunnels are tightly packed with coarse frass and are 1/6 to 1/4 inch in diameter. Frequently, tunnels of emerged insects are exposed on the surface of milled lumber.

Consumer Information Regarding Wood Destroying Insects

This consumer information sheet answers commonly asked questions about inspecting for and controlling wood destroying insects.

1. I think I may have termites (or other wood Destroying insects) in my home. How can I be sure?

Call a licensed pest control firm to inspect, and always get a second or third opinion. If you can collect a specimen of the insect you may wish to take it to the Maryland Cooperative Extension Service Home and Garden Information Center for identification.

2. What is the proper way to treat a home for termites?

The basic principle in treating for subterranean termites is to establish a continuous chemical barrier in the soil immediately adjacent to the foundation walls, both on the interior and exterior of the structure. This is normally accomplished by injecting the chemical (termiticide) beneath the soil. The treatment methods will vary depending on the construction of the structure. The methods used are slightly different for homes with basements as opposed to those with crawl spaces or those with slab on ground construction. The amount of termiticide used will also depend on the size of the structure to be treated. Before contracting with a firm, ask for a written proposal that details the method of application and the approximate amount of termiticide to be used.

3. Once my home is treated, am I guaranteed Against reinfestation of termites?

Even if your home is treated, no one can guarantee that you will never have a termite problem again. Termites only need a small gap in the chemical barrier to continue to gain access to your home. If the soil around the home is disturbed, it can affect the chemical barrier and allow access for termites. For this reason, most pest control firms give a one year renewable arranty on termite work. Typically, the warranty states that if a reinfestation occurs during the lifetime of the warranty they will retreat at no cost to the consumer. Additionally, some firms also offer repair warranties that give coverage for termite damage that occurs subsequent to their treatment. Be sure you read and understand any warranty that is offered.

4. What Is The Proper Way to Treat a Home For Carpenter Ants?

Unlike termites, carpenter ant colonies are not located beneath the soil. Therefore, a termite treatment will not aid in controlling carpenter ants. Carpenter ant control can be very difficult. The key factor in bringing them under control is to find the nest. The most complete control is accomplished when the nest is located and treated. Infestations can be reduced by treating travel routes that the workers use while foraging. Outdoor barrier treatments can help reduce infestation that originate outdoors.

5. One firm recommends fumigation while the other Recommends topical application, who is right?

Fumigation and topical application of a liquid insecticide are two approved methods used in controlling infestations of wood boring beetles. Both have their advantages and disadvantages. One advantage to the fumigation process is that the fumigant will kill all life stages of the beetles (eggs, larvae, pupae, adults). A disadvantage in the eyes of some is that the fumigation process can be expensive. The topical application of liquid insecticide is generally less expensive. However, it does not control all of the life stages of the beetles. The pesticide is applied to the wood surface and penetrates a short distance into the wood. The insects are killed when they come into contact with the treated area of the wood.

6. What termiticide works best?

There are currently a number of termiticide (termite pesticides) products on the market. All have been proven to be effective in controlling termites when applied properly in accordance with label directions. One product does not necessarily do a better job than another in controlling termites.


For further information regarding either inspection for or control of wood destroying insects you can contact the Pesticide Regulation Section of the Maryland Department of Agriculture at 410-841-5710. Another excellent source of information is the Maryland Cooperative Extension Service Home and Garden Information Center. Contact them at: extension.umd.edu/hgic​

Send E-mail to Robert Hofstetter​