TermiteTalkTM Blog

The Queen Reigns Supreme – How Termite Queens Prevent Others from Reproducing

2009-12-21T13:42:12-05:00

The original queen in the colony is capable of chemically blocking development of the reproductive potential of all members of the colony. The king and/or queen produce a pheromone that circulates through the colony and inhibits the formation of other (secondary) reproductives.

The inhibitory pheromone produced by the queen prevents development of female secondary reproductives. This substance is circulated through the colony by immature stages that routinely consume the feces of nestmates.

When the queen dies, production of the blocking pheromone stops, and secondary reproductives may be produced.

In the Reticulitermes species, the queen and king may be replaced by numerous secondary reproductives, and the colony may become very large with the added productivity of many queens.

Termites Dig Deeper for Food During Cooler Months

2009-12-04T11:52:14-05:00

Winter brings some changes in the daily routine of subterranean termite colonies. Foraging tunnels may be somewhat deeper for those species that travel near the soil surface, and food sources that are exposed to cold temperatures may be abandoned.

In heated buildings and the soil adjacent to heated basements, tunneling and general activity may be little changed. During most of the year, queens lay eggs at a steady rate. The number of eggs produced by the queen varies depending on the species, and the age of the queen.

In southern regions, with warm winter temperatures, egg production is continuous throughout the year, although there are seasonal fluctuations. For termites living in temperate regions, which have low winter temperatures, egg production is often suspended during the cold months.

Termite Workers – Nature’s Original Renaissance Men and Women

2009-11-23T13:24:37-05:00

Termite workers are wingless and have hardened mouthparts. A termite worker's head is also hardened, but its body is not and it can be subject to drying if it does not remain in a moist environment.

In some colonies, there are different size (major and minor) workers and their tasks are linked to their size and age. Young or recently developed workers usually remain in the colony to do general repair and maintenance work on the galleries, and they are responsible for caring for the queen and eggs. Older workers are primarily responsible for foraging for food away from the main nest.

About 10 percent of the workers in a termite colony are away from the nest foraging for food. For termite species that do not have soldiers in the colony, the older workers are responsible for defending the colony from invaders.

Termite Queen Egg Production Depends on Species, Age and Climate

2009-11-11T10:22:45-05:00

The queen and king are groomed and fed by workers, which enter the royal cell through small openings in its hard protective wall. Queens lay eggs at a steady rate every day. Workers move the eggs to incubation chambers.

The number of eggs produced by the queen varies depending on the species and the age of the queen. In tropical regions, egg production is continuous throughout the year, although there are seasonal fluctuations. In more temperate regions, termite egg production is often suspended during the cooler months.

After hatching, young immatures are taken to nursery chambers where they are fed and groomed by workers. They are moved to other chambers in the nest until their final molt into workers or soldiers.

How a Termite Queen Builds a Colony

2009-10-22T10:07:02-04:00

The role of the queen in a termite colony varies and changes over time. After pairing with a male, she begins her job as "founder" to get the colony started. She has to locate a suitable nest site, help excavate it, and then start producing eggs that will become workers.

Egg production is slow at first, but increases year by year; the queen maintains peak egg performance for seven to 10 years. Once the secondary queens - which are produced within the colony - begin egg-laying, colony size (number of workers) increases rapidly.

A colony of about 1,000 workers at two years can multiply into 300,000 workers in five more years. Secondary queens are usually located in satellite nests away from, but connected to the main nest, so colonies can grow in size and number of individuals.

Three Primary Roles of Subterranean Termite Soldiers – Protectors, Construction Workers and Organizers

2009-10-05T09:50:37-04:00

A soldier's role in a subterranean termite colony is more than the name implies. Considering soldiers' large heads and mandibles, they are well equipped to battle insects (typically ants) that invade the colony. An alarm pheromone can signal such an invasion and bring soldiers to the site of the attack. However, native subterreanean termite soldiers make up only about two percent of the colony's members, so they can be easily overwhelmed if the ants come in large numbers.

Another responsibility for soldiers is to use their oversized and hardened heads to plug holes in the mud tubes that extend from the soil to a food source above ground. These breaches in the tube walls will quickly be patched by workers.

There also are some more subtle roles for soldiers - as organizers. A group of workers isolated in the top of a test tube, and separated from food (wood) by an inch or two of soil, do not tunnel to the wood unless there is at least one solder in the group.

Growing Pains – Termite Body Size & Colony Size Depend on Maturity

2009-09-21T11:33:07-04:00

Life in the termite colony moves at a slow pace in general, certainly for the first two years. The queen is just beginning her seven to ten years of peak egg production, and the number of individuals in the colony is very low. Colonies that were started this spring with a pair of adults (queen and king) contain less than a dozen nymphs - and maybe one soldier.

By this time next year, there may be about 400 individuals (the range can be 51 to 984), and there may be as many as eight soldiers. This percentage (usually two percent) of soldiers in a colony remains in mature colonies.

The body size of the nymphs and soldiers in young colonies is significantly smaller than those in mature colonies. It seems what a young colony needs is numbers of individuals; they may be small, but they get the job done.

How Termites' Random Foraging Behavior Impacts Termite Control

2009-09-01T16:16:28-04:00

Application of liquid termiticide in the soil around the perimeter of a building requires specific tools in the hands of an experienced professional. The end result must be a continuous band of treated soil adjacent to the foundation wall.

The requirement for an unbroken band is linked to the foraging behavior of subterranean termites. Worker termites moving in the soil close to a house or office building can safely pass through a two-inch gap of untreated soil. Interestingly enough, termites forage for suitable food randomly in the soil, and do not actually search for these gaps in the soil. In fact, they are more likely to come into contact with the treated soil.

Control of subterranean termites is dependent on this random foraging behavior, the efficacy of modern termiticides and professionals' ability to apply materials in the soil.

Watch Out for Fall Termite Swarmers

2009-08-17T15:20:16-04:00

Swarming is a spring activity for most - but not all - species of subterranean termites. Flight times for species vary based on favorable weather conditions, which means that not all termite reproductives swarm at the same time.

In the eastern United States, the major species typically swarm about a month apart, with Eastern subterranean termites (Reticulitermes falvipes) going first in April, followed by dark Southern subterranean termites (R. virginicus) in May.

There is one termite species, light Southern subterranean termites (R. hageni), which prefers quite different weather conditions, opting to swarm in the fall. Swarms of this species may extend from August (cities along the eastern seaboard) to November (in the Deep South). The winged adults in this species are slightly smaller and pale brown, and often swarm during the same time of day as the spring swarmers (late morning). This species' size and color often gets it confused with ants that swarm at the same time of year.

It’s Clean-up Time – Termite Workers Help Groom Nestmates

2009-08-05T14:07:44-04:00

Grooming is an important behavior for insects. It keeps them clean by removing dirt, fungi and other harmful microorganisms from their bodies. For most insects, such as cockroaches and house flies, grooming is strictly do-it-yourself.

For social insects, such as termites, it's cooperative - workers groom other workers, workers groom soldiers and workers groom the reproductives (including the queen). Grooming is done with the mandibles, basically by gently "chewing" over the body surface of a nestmate. Sometimes, however, it is a little more enthusiastic than gentle (probably the rookies), and body parts get bitten off! So, life in the colony can be a little difficult for the average worker, depending on who groomed you last. Workers may be missing parts of their antennae (easy to nibble off), a leg or part of a wing pad.

Block Party – Termites from Different Colonies Mingle at Neighborhood Food Sources

2009-07-20T10:09:54-04:00

Subterranean termite colonies grow and expand their foraging territories (below ground) during summer and other seasons of the year. As foraging "boundaries" become indistinct, worker termites from adjacent colonies may intermingle at common food sites. This meeting may occur in natural areas or in urban neighborhoods, where it is likely to have more than one termite colony infesting a house (at one time or different times, particularly in high termite areas like the Southeast).

At these common feeding locations, there are varying degrees of "getting along" between workers of different colonies. Unlike wasps and ants, subterranean termites tend not to distinguish or be upset by nestmates and non-nestmates mingling at their food sites. The soldiers in these colonies are often found attacking natural predators (typically ants), and not termites from other colonies.

Mulch – the Perfect Termite Hiding Spot and Highway

2009-07-06T18:23:49-04:00

Termite foraging during the summer can include tunneling in the soil close to the surface - especially in favorable locations, such as under bark mulch and stone and gravel ground covers. Soil temperatures and moisture under these materials can be favorable for termite foragers, which require moist conditions.

Termites might feed a little on the mulches we use around our homes but mulch has no nutritional value to them and they will quickly look for something else. However, mulch around homes (including bark mulch) can provide termites a bridge over termiticide-treated soil and access to structural wood. Research suggests that gravel mulch can also create a favorable environment during the summer. Under this material, termites can spend time feeding on roots and construction debris. While gravel provides some ideal conditions, it has been found to be more effective than bare soil in keeping termites away from homes.

Swarms Over, Back to Business as Usual with Subterranean Termites in the Summer

2009-06-22T11:14:35-04:00

Now that the first day of summer has officially come and gone (June 21), the activity inside a subterranean termite colony is beginning to settle down to the hum-drum events of foraging and eating. Past is most of the frantic activity associated with releasing the swarmers - selecting the right days (after a rain, limited wind and optimal humidity), the best time of day, how many to "launch" at a time, and how many launches will be needed to get them all out. Of course, all those males and females had to be fed before they left (no lunch pails outside the colony).

Finished are the days (and nights) of soaking springtime rain. This moisture created all sorts of problems inside the colony, especially if parts of the colony were flooded. Seasonal conditions resulted in the death of many workers, and now the workforce is smaller. But the secondary queens kicked in with plenty of egg production and the number of workers now is increasing. The weather also is more predictable. The upper layer of soil is warm and moist, and there is plenty of food to be found. Life is good.

Termites as the Model for Biofuel Conversion

2009-06-08T13:52:39-04:00

Climate change and fluctuating oil prices are creating an urgent need for eco-friendly fuels, such as bioethanol. Ethanol is already an ingredient in some gasoline. One of the crucial steps in biofuel production is the breakdown of cellulose to simple sugars, such as glucose. Sugars can be fermented to produce ethanol - a sustainable fuel.

Plant material (including farm and forestry waste) is an abundant source of cellulose and a potential source of fermentable sugars for biofuel. However, cellulose is difficult to convert into sugars - but termites may have the answer.

Wood-infesting termites possess a variety of enzymes that efficiently (and quickly) break down cellulose into usable sugars. This bioconversion is done primarily by bacteria and protozoa in the termite gut, but some termite species can produce the powerful enzymes themselves. Research on the extraordinary termite gut may lead to the design of bioreactors that can produce biofuels from almost any plant material.

Striking it Rich: Termite Techniques for Finding Food

2009-05-26T10:29:25-04:00

The food-finding habits of subterranean termites seem to be based on where they think wood should be, not on knowing where it is exactly. (In most species, the worker termites do not have eyes and therefore, cannot "see" the location of wood.) A termite colony's strategy goes something like this:

Cellulose (wood and other similar material) is extremely abundant above ground and below ground - if you tunnel randomly and long enough in the soil, you are bound to find some.

Follow objects (like rocks and tree and shrub roots), cracks or gaps in the soil - this will likely help you locate a food source.

Follow increasing amounts of soil moisture - this is best for survival (termites need moist conditions) and more likely to lead to organic matter.

Follow the scent of fungi associated with food - many of these microorganisms attack and break down wood. You can often find more termites where there is fungi.

Finally, the colony sends out a large number of workers in search of food - the more you send, the better chances you have to get a hit.

As soon as someone gets a hit, they return to get help, but they leave a chemical trail behind so the new recruits can find their way to the food.

Termite Outsourcing: Bacteria Help Many Species Break Down Cellulose

2009-05-14T09:44:23-04:00

Cellulose is the most abundant organic material on earth, and it is one of the most durable - we build houses, bridges, boats and even airplanes with wood. Unfortunately, various insects have evolved to use cellulose for food and survival. Many insects nest in wood, slip through it to lay their eggs, or tunnel into it to hibernate, but few actually eat wood. The reason: cellulose is very difficult to "break down" into a usable food.

All termites can break down cellulose, but many termite species simply "outsource" this job to a select group of protozoan, bacteria and other organisms that live in their gut. The termite pays a small price for this service - the microorganisms take some of the energy from the wood particles during the digestion process, but there is plenty of food-energy left for the termite. The protozoan and bacteria, in turn, depend on termites - they have outsourced their distribution to them. Young termites ingest the feces of older termites to get their "infusion" of microorganisms and start feeding.

The Power of Teamwork: Termite Colonies Designed for Cooperation

2009-05-06T13:49:01-04:00

The subterranean termite colony is thought by some to function as a "super-organism," which means individual worker and soldier termites or groups of these types work together to ensure the colony's survival. For example, some termites have the responsibility to do general housework and repair. They spend their time removing mold and mildew from tubes or tunnels in the wood, repairing holes in tubes, and shoring up the walls of tunnels in the wood with soil.

Most individuals engage in grooming each other (there are no mirrors underground). This grooming is important for the survival of the entire colony because grooming removes potentially damaging bacteria or parasites from the bodies of other termites.

Soldiers do not feed themselves (those big mandibles get in the way), so they are fed by worker termites - whose safety, in turn, depends on the soldiers. Some individuals remove and bury dead termites - somebody has to do it or these bodies would contaminate the colony.

Springtime Flowers and Termite Swarms

2009-04-20T10:58:39-04:00

Spring is the swarming season for most subterranean termites. There are several subterranen termite species and they don't all swarm at the same time. (On the other hand, dampwood and drywood termites typically swarm in the summer.) Species generally swarm based on favorable weather conditions. Varying conditions may mean that swarms will occur at different times. For example, some species prefer more moisture than others. Separation in swarm timing may be a matter of a few weeks, or time of day. Swarms can be loosely linked to the blooming of certain trees. For example, one of the Eastern subterranean species typically swarms when the dogwood tree buds swell and the flowers first appear. The swarming of a closely related species was once linked to the blooming of chestnut trees, but a blight killed most of those trees, so we have to find another marker.

Guess Who’s Coming to Dinner: Termites

2009-03-30T17:13:11-04:00

It does seem quite amazing that tiny insects tunneling underground are able to locate houses perched on top of the ground, and then find a way inside to feed on the wood. How do they do that? First, they have thousands of years of experience; second, they practice to perfection one of the lessons you learned in school: sharing and cooperation. Lastly, subterranean termites firmly believe in the phrase "better living through chemistry."

Worker termites move underground along natural edges and channels: buried logs, tree roots, and pipes. Sometimes they make their own path through the soil, usually in the direction of moisture. This tunneling and foraging behavior helps them survive because it usually leads to a food source (and that may be your house). When one of the wandering workers locates food, the sharing and cooperation behavior kicks in. The individual worker or a small group of workers will be at the food for a short time, but then return to the nest or go out and recruit other workers to the food. Sharing food is key to colony survival. Because workers feed and groom each other, the energy put into foraging by individuals pays off for everyone.

Now for the chemistry - this is what makes termite food scavenging work. Workers returning from the newly found food leave a chemical trail behind them. Other workers pick up the scent trail and follow it back to the food through the maze of underground tunnels. These workers may feed for a while and then move out to recruit other nestmates. Soon there is a large number of workers at the food site. If things go very well, they might move the queen to the new site - then the party really starts to rock.

Sign of the Times: Termites Respond to Climate Change

2009-03-09T09:56:00-04:00

The gradual change in the North American climate over the next 10 years may not produce a noticeable change in termite behavior or activity. During this time, the average global temperature is expected to be 0.3 degrees warmer than in 2004. Regional changes in temperature and rainfall – hot weather, flooding – may have immediate or indirect effects on this insect. Long-term dry conditions can increase the potential for forest fires, which would eliminate colonies. Regular flooding in a region would reduce the abundance of some colonies. But, increased temperature and rainfall can also enhance tree growth, and that may increase termite populations.

Perhaps the biggest influence climate change will have on termites will be the influence it has on house construction. Building practices that emphasize energy and water efficiency, and long-term protection from wood decay, will provide termite protection.

Changes in rainfall and more temperate winter temperatures may provide suitable conditions for termites in some regions in the northern and western U.S. Termites do not normally occur in parts of these regions, primarily because the natural vegetation is prairie grass and the cold winters produce very dry conditions. (It’s not the cold, but the dryness that deters termites.) However, any movement of termites into these regions would be slow. And there may be some factors that would prevent it, such as soil bacteria, fungi or other insects that would attack worker termites as they foraged in this new habitat.

Spring climate conditions in northern regions of the U.S. can disrupt and drastically limit the swarming activity of colonies. Without extended periods of mild weather and light rainfall, swarms will not be successful and colony spread will be reduced. These conditions force colonies to resort to splitting or “budding” as their means of reproducing, which means there would be less exchange of genetic material with other colonies. Breeding between termites within a colony causes a genetic condition that reduces a colony’s internal growth potential and external growth potential to form new colonies or groups.

Reference: The Physical Science Behind Climate Change. 2007. W. Collins, R. Colman, J. Haywood, M.R. Manning, and P. Mote. Scientific American 297 (2): 62-73.

Surviving the Storm: Termites in Severe Weather

2009-02-23T11:36:00-05:00

Weather extremes can influence the local populations of almost any insect, even subterranean termites. Over the past seven or so years, termite experts have reported a decreased number of swarms during the spring and fall, as compared to typical averages. While experts cannot confirm one factor that is responsible for this decline in swarm activity, there is some evidence that indicates both lack of rainfall and too much rain can reduce the amount of swarmers that are produced in the colony – thus reducing the number of swarmers available to swarm. Unfortunately for homeowners, a decline in termite swarms does not mean these insects are less active – it means their infestations are less visible. Homeowners may be unaware of an infestation until damage has occurred.

While last year was a slow year for termite swarms, experts believe we have just passed the midway point in the weather cycle affecting these insects. Experts report swarms may become more prevalent each year as the weather pattern continues to shift. In the meantime, check out some interesting facts below on the impact of rainfall and temperature on swarms.

Research has shown that floods can reduce the size of termite colonies in the soil below the floodwater. Under normal rainfall conditions, water moves through the soil within a few hours, and termite colonies are unaffected. If the water stays in the soil, then problems can occur. Flooding doesn’t usually kill the colony but it does eliminate some of the workers, which can slow things down for awhile. Colonies do not move to high ground during a flood, but rather shift to a lower level of activity – reduce the amount of foraging. The colony may be back to full strength in 1-2 years. Flooding in New Orleans following Hurricane Katrina did not eliminate the termite colonies in that city. The flooding that has occurred in the South and Midwest in 2008 is not likely to eliminate termite colonies either.

High daytime temperatures can also heat and dry the surface of exposed soil and certainly kill some insects there, but soil covered with mulch or grass is shielded from direct heating. Termites that forage close to the soil surface would be repelled more by the dry conditions than they would be by the heat. High heat conditions are limited to daytime and may be unfavorable for only a few hours. During the thousands of years that termites have been in North America, they have undoubtedly experienced extremes in temperature and rainfall and have adapted to these conditions.

Reference: Subterranean Termite Behavioral Reaction to Water and Survival of Innundation: Implications for Field Populations. 1995. Brian T. Forschler and Gregg Henderson. Environmental Entomology 24: 1592-1597.

Things that Go Bump in the Basement: Termite Facts and Fiction

2009-01-26T10:37:00-05:00

Around the 1st century, the Chinese learned that “white ants” could destroy houses. At the same time, they incorporated termites into a few herbal medicines – an early form of turning the tables on your enemy! In fact, termites can be a healthy meal in some cultures – the food value of fresh termites is 126 calories / 3.5 ounces (25 grams of protein and 2.5 grams of fat).

The bad blood between ants and termites probably has a long history. Many ant species are predators of other insects; they forage for caterpillars, beetle grubs and even other ants in the soil and up in trees. When they encounter termite colonies – soup’s on! Ants have powerful jaws and they know how to use them. Termite colonies have “soldiers” to protect the workers. These termite soldiers have large and powerful jaws, but there are not enough of them. It can get ugly – ants usually win.

After Hurricane Katrina, there was a false rumor circulating about wood mulch. The rumor was that house debris and trees were turned into mulch, and this mulch contained termites. Wrong! The rumor was not only false, but it also would be impossible for termites to live through the process of making mulch, and to survive in bags of mulch sold in stores.

The myth of the reward for a termite queen is still circulating. This is the belief that a pest control company will pay for a live termite queen. Wrong! There are some movies and other accounts of people digging to get a large queen termite, but these are species that typically occur in the tropics. In fact, the queens of termites in the U.S. are not very large, and not valuable if taken alive or dead. Don’t start digging.

References: Handbook of Urban Insects and Arthropods. 2005. Wm. H Robinson. Cambridge Univ. Press: Cambridge, U.K.

Man Eating Bugs: The Art and Science of Eating Insects. P. Menzel and F. D’Aluisio. 1998. The Speed Press, Berkeley, CA.

Feeding the Not-So-Picky Eater: Termites and Their Diet

2008-12-18T10:53:00-05:00

Wood is a very strong material and very few animals are able to use it (eat it) as a food. Termites can consume wood but they need help from some unusual protozoa and bacteria, and a few friendly fungi. This is a “get-along-to-go-along” relationship that has been in place for a long time. It enables termites to eat almost any kind of wood anywhere in the world.

Wood-decaying fungi help termites in several ways: they provide nutrition by supplying vitamins; they detoxify certain types of wood; and some fungi produce feeding stimulants to keep termites workers eating the wood. But not all fungi are helpful. Some wood-decaying fungi produce toxic substances that prevent termites from feeding, or they remove nutrients from the wood.

It is the various protozoa and bacteria in the gut of termites that are the most important and the most interesting to their eating habits. Several species of protozoa live in the gut of termites and they feed on the fragments of wood they find there. These protozoa also need help in digesting cellulose (wood), so they have special bacteria living in their gut that complete this process. The interdependent cycle works like this: termites need the protozoa and the protozoa need the bacteria, and nobody can live alone. This is a mutually beneficial arrangement for everyone: the termite, the protozoa, and the bacteria.

Now that we have bacteria digesting the wood, what happens next? Those bacteria living in the stomachs of termites, some with the name of Methanobrevibacter, are giving the termites gas! Specifically methane gas – the stuff that wrecks the ozone layer and contributes to climate change. One research report states termites are responsible for 30% of the methane in the atmosphere; another report lists the contribution at 5% (cows are thought to be responsible for about 11%).

References: Symbiosis and Evolution. 1971. Lynn Margulis. Scientific American 225 (2): 48-57.

Putting on Airs. 1995. May Berenbaum. American Entomologist (Winter); 199-200.

Giving Nature a Hand: How to Keep Termites in Check

2008-11-24T10:03:00-05:00

Modern termiticides have provided homeowners with long-term control of subterranean termites since the mid 1940s. The safety and effectiveness of these materials have increased with the introduction of new types of chemicals, and new application equipment. All termiticides are evaluated by the U.S. Forest Service, and must be proven effective for at least five years before being approved and available for use. But the products used by professionals last 2-3 times longer than minimum requirements. New control methods are always being considered, and some may be a part of future termite control strategies. Advances in research have opened possibilities for both chemical and non-chemical methods. Below are possibilities for the future.

Most termite species rely on microorganisms in their gut to help them digest the wood they eat. Without these organisms, termites would not get nutrients and energy, and would die. This important relationship between microbes and termites might be the basis of a control strategy. If termites in a colony could be fed something that killed the microbes in their gut, the workers would soon die and the colony would be eliminated.

Termites depend on chemicals called pheromones to remain organized in a colony, to recognize nestmates, and to mark trails between a food source and the nest. The chemical structure of some termite pheromones has been determined, and might be used in a control strategy. For example, artificial trail pheromone might be used to direct foraging workers away from structures.

The genetics of termites around the world have been investigated, primarily for identifying species. The technology of termite genetics may be useful in finding new control strategies. Surely there is some characteristic linked to a gene sequence that might be used to control these insects, such as a gene for small mandibles that makes eating difficult.

Reference: Termiticide Efficacy Results: 2006 [USDA-Forest Service] Termiticide Report. 2007. T. Wegner, T. Shelton, C. F. Peterson, and J. Mulrooney. Pest Control Magazine (February): 58-69.

DIY Termite Control: Leave It to the Pros

2008-10-21T18:00:00-04:00

There are small problems around the house the average homeowner can fix. A trip to the home repair store can get you some advice on what to do, and the parts you need to do it. Termite control is a serious matter – this is not a stuck door or a leaking sink, this is the entire house that is a stake. Your house is probably the largest single investment you have. Controlling or preventing an infestation of termites is not something you want done by an amateur – and that would be you.

Effective and long-lasting termite control requires 1) training and experience, 2) insecticides (termiticides) formulated specifically for termite control, and 3) the tools (pumps, hoses, soil rods and nozzles) to treat the soil. These components are linked. To buy and use termiticides you must be trained and then certified as capable to use them by a state and federal agency. You must apply termiticides according to specific directions given by the manufacturer, and with the tools listed in the product directions. Each house is different and that makes each application slightly different, and that is where experience becomes important. A professional knows what to do and how to handle the subtle differences in each house.

Termite control is not simply treating the soil around the house. Yearly inspections are a part of the treatment, and this second step requires the same level of training and experience. Subterranean termites can make their way through a two-inch gap of untreated soil, and they may find such a gap any time after the house is treated. Termiticide applications are evaluated every year by inspecting the house (foundation) for signs of termite activity. Inspections must be done carefully or the house is not protected.

Reference: Survivorship and Tunneling Activity of Reticulitermes flavipes in Response to Termiticide Soil Barriers With and Without Gaps of Untreated Soil. 1994. Brian Forschler. Journal of Entomological Science 29: 43-54.

From Suburbs to Cities: Termites Make Their Home in Both Locations

2008-09-22T09:42:00-04:00

It seems to make sense that subterranean termites would have a difficult time surviving in cities – with all of the buildings and concrete, and little exposed soil. But they do just fine in large urban areas. New York, Paris, Singapore, Hong Kong, Shanghai and Tokyo have their share of termite infestations. Swarms can occur in a hotel coffee shop on the 1st floor or in an apartment on the 17th floor. Subterranean termite colonies can survive in large cities by feeding on buried wood around building foundations, and sometimes in ground debris in parks and vacant lots. Colonies may not produce yearly swarms, and swarming may be in basements. In cities, colonies can reproduce by “budding,” which is when a portion of a large colony divides and forms a new one.

There are more termite colonies in suburban areas, and they occur more often in subdivisions built on land that was once wooded than agricultural land. There are natural habitats (parks, woodlots and dead trees) in or near suburbs and these can serve as a ‘reservoir habitat’ for termites. Swarms that originate from colonies in these reservoirs can provide the pairs of termites (future queens and kings) that will found new nests around houses and buildings.

As termite control materials and application methods become more effective, the number of termite colonies in both cities and suburbs might start to decline. This will be especially true in large cities, where there is a long history of termite control and there are few reservoir habitats to provide termite queens and kings with areas for new colonies. In suburban areas, where there are usually some natural areas, termites may have a better chance of surviving new control methods, but maybe not for long.

Reference: Eastern Subterranean Termite Foraging Territories and Populations in Toronto. 1989. J.K. Grace, A. Abdallay, and K.R. Farr. Canadian Entomologist 121: 551-556.

A Bad Reputation: Termites Share Their Good Side

2008-08-25T13:25:00-04:00

There are many species of termites that occur naturally in the U.S., but only a small number are pests in houses and other structures. So, what are the rest of the termites doing if they are not thinking of ways to get into your house and chew on some timbers? Well, mostly good things.

Termites are one of only a few animals that can feed on cellulose (wood); they can use it as a food source. Cellulose is a strong and stable material that is naturally resistant to decay. But in natural habitats, it’s necessary to break down dead trees and other woody material and return nutrients to the soil. Termites do that with the help of some special microbes in their gut. The value or benefit of termites is most evident in the tropics where there are extensive forests and the soil can be shallow. Termites are busy there converting dead trees into useful soil.

Animals looking for a high protein meal do not overlook the termite colonies. The typical colony is large (thousands of workers and soldiers in the nest) and not difficult to find. Several animals, including chimpanzees, birds and ants will break into colonies to get a meal. For most of these animals, termites are not their main food source, but they can be an excellent source of proteins and fat. Humans have also figured out the food value of termites. Several cultures have recipes for cooking and eating termites. Yum.

Another way to look at termites is their position in the food chain in habitats that have a lot of trees and woody plants. In these habitats, termites may be the primary “reducers” of wood cellulose into usable by-products. Otherwise, forests would be littered with dead trees.

Reference: Urban Entomology: Insect and Mite Pests in the Human Environment. 1996. Wm. H. Robinson. Chapman & Hall, London, U.K.

Southern Charm: Why Termites Make Their Home in the South

2008-07-28T21:23:00-04:00

The present distribution of subterranean termites in North America is probably very close to what it was when the Pilgrims arrived. The climate, soil conditions and available food supply in the southern U.S. favored the many species of native termites. Mild winters allowed for nearly year-round feeding and tunneling in the soil, the predominant sandy loam soil held moisture and was relatively loose, and the fast growing, short-lived pine trees in the region provided plenty of food. In general, these conditions have changed little, except termites now feed on the pine lumber in houses and not on the forest floor. Building practices during the early settlement of the southern states favored wood close to the ground, and houses with narrow crawl spaces and no basements.

The native subterranean termite species are still abundant in southern states, but not any more than they were originally. Several species have extended their range into northern states, to regions that did not have termites originally. But they are not as successful as their southern relatives. Soil conditions are rocky and often dry in the North because the region has lower rainfall; the winters are also long and springtime weather is erratic – both of which can disrupt swarming. The food supply in northern regions is primarily hardwoods.

The Formosan termite has joined the ranks of the native subterranean termite in the southern U.S. This species was introduced from Asia, and is now in states from Florida to California. As an introduced species it may not have the parasites and predators that the native North American species have, so it does very well. Formosan termite colonies are larger than the native species and their construction is slightly different, making this termite species more destructive.

Reference: Handbook of Household and Structural Insect Pests. 2000. Edited by R.E. Gold and S.C. Jones. Entomological Soc. of America.

When Termites Fly: Why These Bugs Take Flight

2008-06-30T02:43:00-04:00

Thousands of winged termites swarm out of underground nest sites in spring —with one objective in mind: to find a mate and build a nest, and eventually establish a new colony. Large numbers of males and females are produced in subterranean termite colonies in late winter and early spring. They are moved to specific locations in the nest (near the soil surface) and remain there until the time is right to leave. They may wait for several weeks, and have to be fed and groomed by nestmates. This scenario is played out in other colonies in the area – that’s important.

The value of swarming is for colonies to ‘exchange’ males and females for mating. In general, colonies use weather conditions to coordinate the release of their reproductives. They wait for calm winds (less than 6 mph) and overcast days following a spring rain. They don’t want a strong wind to blow everyone away from the big dance! Wet soil helps the new couples to build their first nest, and the extra humidity helps survival. Not all swarms occur outdoors. Sometimes the colony misjudges the release point and thousands of winged termites are released indoors. Regardless of the site (or lack of exchange with other colonies), the pairing, shedding of wings, mating and potential founding of a new nest all proceed without a hitch.

Colonies usually produce swarms once they have reached a certain size – based on the number of workers in the colony. The average colony produces swarms every year, but the number released varies. The release is usually staggered over a few days. There may be a large ‘first’ swarm, followed by smaller second and third swarms. Termites have a lot of swarming experience, and seem to make it work.

Reference: Urban Entomology: Insect and Mite Pests in the Human Environment. 1996. Wm. H. Robinson. Chapman & Hall, London, U.K.

Termite Damage: Little Bugs, Big Problems

2008-02-27T06:26:00-05:00

Termites are considered the number one threat to homes in the U.S. — a risk greater than fire, flood and wind. While termites are not as visible or dramatic as these other dangers, their slow, methodical eating of house frames and support timbers can be very costly. In fact, according to the National Pest Management Association, termites cost Americans more than $5 billion in damages annually. These hungry termites are found in almost every U.S. state, except for some regions in the West and North.

What separates termite damage from fire, flood or wind damage is its subtlety. Termites can infest wall studs and foundation timbers for years without visible signs of damage. One colony can multiply into several colonies with several entry points and feeding sites.

Signs of termites are often hidden or overlooked by the average homeowner. Swarms of winged termites in the spring may be misidentified as flying ants. Mud tubes along a foundation wall may be difficult to see in the dim light of a crawlspace. Homeowners in termite-prone areas should contact a termite professional to inspect their home to prevent and treat termite damage.

Termites have earned their most dangerous threat status due to their classification as social insects, which means they live in colonies and take care of one another. They groom and feed each other, protect the queen and the eggs she lays, and maintain the structure of the nest. With enough food (i.e. wood in and around your house), colonies can grow to support hundreds of thousands of workers. When they grow too large for one nest, colonies can divide to form new and separate colonies within the same structure. Left undetected and untreated, these termites can cause extensive damage.

Reference: Handbook of Household and Structural Insect Pests, edited by R.E. Gold and S.C. Jones. Entomological Society of America, 2000.