Wasps and bees too near human activities spell inevitable conflicts. Yellowjackets cause almost all bee stings and are common picnic pests in late summer. In balance, though, these insects are beneficial as predators of pest insects. In their late-season scavenging, they will tackle insects as large as caterpillars. Banded yellow and black yellowjackets nest underground. They may fly as far as 1,000 yards from the colony, so often the nest is difficult to locate.

Nest destruction is the best control when nests are too close to homes or other areas of human activity. If nests must be destroyed, follow these steps:

  • Use an aerosol “wasp and hornet” product with a jet spray
  • Go outdoors with the spray and a flashlight after dusk when the adult yellowjackets are in the nest. Defenders are less likely to emerge at this time of day.
  • Spray the nest entrance. In most cases, a single application should destroy the colony although some newly emerged wasps may be seen for up to a week later.
  • If nests are further away and yellowjackets visit only at picnic time, consider preserving them as part of the balance of nature.


Tick season in Colorado starts in March and usually peaks sometime in May. Ticks are very common in Colorado, especially in areas where there is a lot of brush. If hiking in the mountains, check for ticks periodically and pull them away from your clothing or before they attach themselves. Insect repellents such as DEET or permethrin will reduce the number of ticks that will climb onto your clothes. The best way to remove a tick is to take a tweezers and slowly and carefully pull it out. Common Colorado ticks and their hosts include the Rocky Mountain wood tick, which lives on small rodents, deer and domestic animals. This is the most common species that bites humans. The American dog tick lives on small rodents, dogs and raccoons, and occasionally bites humans. The rabbit tick lives on rabbits and other small rodents and sometimes bites humans. There are 30 species of ticks reported in Colorado.

What Diseases Do Ticks Transmit in Colorado?

Colorado tick fever is by far the most common disease transmitted by ticks in Colorado. About 100 cases are reported annually, concentrated in Larimer, Boulder, Jefferson and Gunnison counties. Because the symptoms are often fairly mild and mimic other common diseases, such as influenza, it is assumed that many more cases actually occur but are not diagnosed. April, May and June are peak months for Colorado tick fever. Other tick-borne diseases are rare in Colorado. Ticks are involved in transmitting tularemia, which is widespread in many populations of wild rabbits. About 10 to 12 human cases are also reported in the state, although most occur among hunters who handle infected rabbits rather than by tick bites. Relapsing fever occurs infrequently in Colorado, with about 2 or 3 cases reported annually. However, incidence is suspected to be several times higher since it is easily misdiagnosed and is rarely reported. Despite its name, Rocky Mountain spotted fever is very uncommon in Colorado and the rest of the western United States. Currently over 90% of the cases occur east of the Mississippi. However, the disease was first described from Montana and was limited to the Rocky Mountain region until about 1930. An average of about 3 cases are reported annually from Colorado. If you find an attached tick and have flulike symptoms and fatigue, contact a physician for proper diagnosis and treatment.

Ticks in the Home

Only one tick can completely develop within a home, the brown dog tick ( Rhipicephalus sanguineus). This is a ‘one-host’ tick that feeds on the blood of dogs. It is fairly common in Colorado, and is usually found on a dog or climbing on walls. It is a subtropical species that maintains itself indoors, unable to survive outdoor winters here. Brown dog tick is most often a problem in kennels. It rarely bites humans and can not develop and reproduce on a diet of human blood. If you find ticks on your dog, treatment of the dog is essential using a flea and tick powder, dip or collar. You also will need to treat places the dog frequents, such as bedding and resting areas.

Using an insecticide, spot-treat cracks along baseboards where ticks may hide. Vacuum ticks and nymphs that crawl up walls and in room corners. It is best to dispose of the vacuum bag once ticks have been collected. Wash all dog bedding. It may take several weeks and multiple treatments of areas in the home to finally eliminate tick infestations.


Damage Prevention and Control Methods Exclusion

Termites look like small white ants. While termites are not a major problem in Colorado, the subterranean species does occur, particularly around landscaped areas with their higher humidity. Termites live on cellulose, the primary source of paper. They will eat the cover and pages in long, wiggly tracks almost like an engraved Jackson Pollack painting. Heat and dry conditions will discourage termites but they do require professional treatment with insecticides. Some building modifications can eliminate any future infestations. CSU’s publication goes into great detail on the type of modifications to consider.

Termites are the most economically important wood-destroying organism in the United States, with approximately $2 billion per year being spent for their prevention and treatment. This high-dollar amount could be reduced if homeowners implemented a number of relatively simple, inexpensive, practical measures around their home and outlying structures that reduce the risk of subterranean termite infestations. Such preventive measures are very cost effective given that a home typically represents one’s largest monetary investment.

Many construction and landscaping features literally can invite termites into one’s home. An awareness of basic termite biology and habits can help you understand the necessity of certain prevention measures. The goal is to recognize and alter conditions around one’s home so as to reduce the termites’ environmental requirements for moisture, food (wood), and shelter.

Termite Biology and Habits

In Ohio and in most other parts of the United States, subterranean termites are the most common type of termites that infest homes. These termites need moisture to survive. They are closely associated with the soil, where they typically construct an underground nest or a series of interconnected nests, hence the name “subterranean termites.” The termites excavate narrow tunnels through the soil, creating a network through which they can travel very long distances (hundreds of feet or more) to reach food. They also transport soil above ground to construct mud tubes (shelter tubes) and to line their feeding galleries in wood. Soil serves as a source of moisture that helps protect termites from the drying effects of air. It also shields termites from predators (ants, birds, lizards, etc.) that feed on them.

Cellulose (especially wood) is the main food source for subterranean termites. In nature, termites feed on dead wood, including roots and stumps. Around homes, termites readily feed on wood mulch used in landscaping. However, any type of mulch provides termites with needed moisture and protection from the elements. In homes, termites often first attack wood that is located close to the soil (i.e., lower parts of the house). They then can follow the framework of the house to gain access to upper levels and floors. As they feed, they excavate galleries in the wood. Termites also can tunnel through inedible materials such as foam insulation, plaster board, etc. as they search for food.
Do not unknowingly invite termites into your home! Employ any of the following measures to help disrupt the termites’ ability to locate moisture, food (wood), and shelter.

Solutions to Termite-Conducive Situations

Problem: Cellulose (wood, dead plant material, paper, etc.) in contact with soil provides termites with ready and unobservable access to food.


  • Keep all wooden parts of the house foundation at least 6 inches above the soil.
  • Keep mulch levels several inches below the siding and wooden parts of the structure.
  • Avoid or minimize use of wood mulch next to the foundation.
  • Remove dead trees, stumps, and roots near the structure.
  • Never store firewood, lumber, or paper against the foundation or in the crawl space.
  • Remove wood debris and form boards.

Problem: Moisture accumulation near the foundation provides water needed for termite survival.


  • Grade or slope soil away from the foundation.
  • Divert rain water away from the foundation.
  • Maintain clean gutters and down-spouts.
  • Install down-spout extenders and splash blocks.
  • Use drain tiles if site is flat.
  • Divert lawn sprinklers and irrigation water away from the foundation.
  • Promptly repair leaking faucets, water pipes, and air conditioning units.
  • Use mulch sparingly (no more than 2 inches depth is recommended).
  • Keep plants and ground covers 3-4 feet away from the house foundation.

Problem: Poor ventilation in crawl space provides water needed for termite survival.


  • Cover approximately 75 percent of the soil surface in the crawl space with a vapor barrier (4-6 ml polyethylene sheeting).
  • Install 1 square foot of vent opening per 300 to 500 square feet of crawl space area (when using a vapor barrier).
  • Install 1 square foot of vent opening per 150 square feet of crawl space area (without a vapor barrier).
  • Enhance cross ventilation.
  • Remove any vegetation covering vents.

Problem: Hidden termite access.


  • Install trellises and trim plants so that they do not contact the house.
  • Do not build flower planters against the house.
  • Regularly inspect cracks or joints in concrete slabs for evidence of termites.
  • Install metal flashing when attaching porches or decks (even when using “treated” lumber) to an existing house.
  • Remove mulch that contacts siding or obscures a clear view of the foundation.
  • Never install foam board insulation (polystyrene) below grade.

Black Widow Spiders

Lactrodectus mactans

Black widow spiders are most recognized for the red hourglass shape on the back. Contrary to legend, female black widow spiders rarely devour the male black widow spider after mating.

Color: Black, with characteristic red “hourglass” on back
Legs: 8
Shape: Round
Size: 3/4″ length; 3/8″ in diameter
Antennae: No
Flight: No

Black widow spiders spin their webs near ground level. They often build their webs in protected areas, such as in boxes and in firewood.

Black widow spiders are often found around wood piles and gain entry into a structure when firewood is carried into a building. They are also found under eaves, in boxes, and other areas where they are undisturbed.

The venom of a black widow spider is a neurotoxin and is used as a defense. Black widow spiders do not bite humans instinctively. The black widow spider bite can cause severe pain. Young children and the elderly are especially susceptible to a severe reaction to a black widow spider bite.

Avoid black widow spider bites by wearing heavy gloves when moving items that have been stored for a long period of time. Spiders often hide in shoes, so check shoes and shake them out before wearing. When spider webs are visible, use caution before putting your hands or feet in that area.

Black Widow Biology, Reproduction, and Behavior:
Above is a little bit of information on black widows, but I thought we would go a little deeper for your safety.
The black widow spider is a cobweb builder whose silk is very strong. The female constructs a web of crisscrossed silk threads with no recognizable pattern and with a dense area of silk, usually to one side, that serves as the spider’s daytime retreat. At night, the female hangs belly upward in the center of the web. She does not leave her hidden web voluntarily. The web typically is situated near the ground in a dark, sheltered site. Webs often are one foot in diameter. The web serves to trap the spider’s food, which includes a variety of insects (cockroaches and beetles) and other arthropods. Outdoors, black widow spider webs are usually built in woodpiles, rubble piles, under stones, in hollow stumps, and in rodent burrows. These spiders commonly occur in outbuildings such as privies, sheds, and garages. Indoors, they prefer undisturbed, cluttered areas in basements and crawl spaces.

The northern black widow spider is similar to the black widow except its habitat is marginal land with sparse vegetation. It is found in stumps, hollow logs, and piles of debris, and only rarely indoors.

Bite Symptoms:
The severity of an individual’s reaction to the black widow spider bite depends on the area of the body bitten, amount of venom injected, and their sensitivity to the venom. The venom travels in the bloodstream throughout the body and acts on the nervous system, causing varying degrees of pain. Some people report very intense pain. There typically is no necrosis (sloughing) of tissues and no conspicuous swelling.

The bite of a black widow spider initially may go unnoticed, but some people report a short stabbing pain. At first, there may be slight local swelling and two faint red spots, which are puncture points from the fangs. Pain soon begins and usually progresses from the bite site to finally localize in the abdomen and back. Severe cramping or rigidity may occur in the abdominal muscles. Other symptoms may include nausea, profuse perspiration, tremors, labored breathing, restlessness, increased blood pressure, and fever. Symptoms often diminish after a day or so and cease after several days. Serious long-term complications or death are very rare.

Preventing Spider Bites:
In order to prevent spider bites, be sure to wear gloves and a long-sleeved shirt when handling stored cardboard boxes, firewood, lumber, and rocks. Be sure to inspect these clothing items for spiders before putting them on. Shake out clothing and shoes before getting dressed.

Install tight-fitting screens on doors and windows to prevent entry of black widow spiders. Also install door sweeps. Seal or caulk cracks and crevices where spiders can enter the house. Install yellow or sodium vapor light bulbs outdoors since these attract fewer insects for spiders to feed upon.

In order to reduce black widow spider populations, it is very important to eliminate their potential hiding places indoors and outdoors. Black widow spiders are often found in undisturbed, cluttered areas indoors, so discard old boxes, old clothing, lumber, and other unwanted items in basements, crawl spaces, garages, and outbuildings. In such areas, store any items off the floor and away from walls. Remove piles of lumber and rubble outdoors. Remove ivy and other heavy vegetation from the foundation. Do not store firewood against the house. Note that these measures also reduce harborages for the spiders’ prey.

Vacuum thoroughly indoors to remove black widow spiders and their webs and egg sacs. After vacuuming, immediately place the vacuum cleaner bag in a plastic bag, seal tightly, and discard in a container outdoors—this prevents captured spiders from escaping into the home. Wash off the outside of the house using a high-pressure hose, paying particular attention to window wells and other undisturbed areas where webs are built.


Mosquitoes are a major insect pest problem in Colorado and may seriously deter outdoor activities and tourism. These insects cause economic losses in cattle and other livestock through blood loss, disease transmission and irritation. Mosquitoes also can transmit certain human diseases such as West Nile virus, Western Equine Encephalitis. The incidence of mosquito-transmitted disease in Colorado is closely monitored by public health agencies.

  • Mosquitoes can transmit certain human diseases, deter tourism, and cause economic losses in cattle and other livestock.
  • Immature mosquitoes, or wrigglers, live in shallow water and feed on microorganisms.
  • The Aedes and Culex/Culiseta are two important types of mosquitoes in Colorado.
  • Larval management is the key to mosquito control.
  • Adult mosquitoes can be controlled with insecticide applications, but a community should agree on how to decide when treatments are necessary.

Managing Mosquito Larvae
The key to mosquito control is larval management. Larvae occur in specific areas and can be controlled by modifying the habitat through drainage, or with insecticides applied to larval breeding sites. Treatments provide control before the biting adults appear and disperse from the breeding sites. Mosquito control measures must be cost effective and environmentally sound. Consider alternatives before application of conventional chemical insecticides.

Habitat Modification
Eliminating breeding sites, or habitat modification, is an effective and long-term solution. Sites can be drained or removed. However, mosquitoes can breed in important wetlands, so habitat modification may not always be an option.

Irrigated agriculture is widespread in Colorado and irrigation systems can be sources of mosquitoes. Farm impoundments, seepage from irrigation pipe, standing water in control structures, irrigated pastures and clogged ditches are all potential mosquito breeding areas. To control mosquitoes on irrigated farms:

  • control seepage,
  • schedule water delivery to avoid excess watering,reduce or eliminate vegetation and debris in ditches and other water containment structures, and eliminate mosquito habitats in impoundments.
  • Fill or drain water-holding areas, and fill or deepen shallow areas preferred by mosquito larvae.

Natural Predators
Fish, dragonfly nymphs and diving beetles are natural predators of mosquito larvae, while dragonflies, birds and bats feed on adults. The mosquito-eating fish Gambusia (closely related to guppies) can be reared in large numbers and released in mosquito breeding sites. Gambusia feed on many kinds of insect larvae, but prefer wrigglers and other top feeders. Although Gambusia are not used extensively in Colorado, some strains can survive our climate and become effective long-term controls of mosquito larvae in some habitats. Mosquito fish have to be released annually in habitats that do not have year-round water. Consult the Colorado Division of Wildlife restrictions and regulations on Gambusia before using this mosquito control method.

Microbial insecticides, especially the bacterial product known as Bti (Bacillus thuringiensis israeliensis), can be as effective as chemical insecticides. Bti is toxic only to mosquito and midge larvae. It is not hazardous to nontarget organisms but can reduce midge populations that serve as fish food.

“Soft” chemical insecticides, such as the insect growth regulator methoprene, are toxic only to insects and other arthropods. They are similar to certain insect hormones and create imbalances in the levels of hormones needed for proper mosquito growth and development. They do not directly harm fish or other wildlife but can reduce the amount of available food.

Mosquito larvae also can be controlled by the application of larvicidal oils or chemical insecticides to the water where they occur or are suspected to occur. Remember, several alternatives to conventional chemical larvicides have been developed because of concerns about applying chemicals to water that might be used for drinking or that contains fish and other aquatic life.

Managing Adult Mosquitoes
If larval control fails, adult mosquito control may be necessary. Adult control generally is done with insecticide applications using ground equipment or aircraft. Mosquitoes are strong fliers, so adult control is most effective if it is done over a large area or on a community basis. Because of the environmental hazards associated with wide-area insecticide applications, it is important for the community to agree on the criteria used to decide when a treatment is necessary.

Some communities decide to spray when there is a threat of mosquito-transmitted disease. Others base their decisions on tourism considerations. Whatever the criteria, it is important to avoid routine spraying that does not take into account the amount of actual mosquito activity and the life cycle of the insect. This results in needless, expensive applications that may result in environmental contamination.

Although mosquitoes can be serious pests in Colorado, there are several effective means of controlling them in the community and around the home. Mosquito management is most effective when all available control measures are integrated into a community-wide mosquito management program.

Mosquito Management Around the Home

  • Eliminate standing water in low spots, ditches, gutters and similar areas.
  • Empty weekly or remove receptacles that collect rainwater (bird baths, old tires).
  • Mosquito netting and tight screens can provide mosquito-free areas.
  • Some mosquitoes are attracted to lights. Reduce unnecessary lighting to make yards less attractive.
  • “Bug zappers” do not reduce mosquito landing or biting. They attract and kill many insects but few are mosquitoes that attack humans. Many of the insects killed are beneficial because they feed on Garden pests.
  • Ultrasonic devices, such as those that claim to mimic dragonflies, do not affect mosquito activity.
  • Light-colored clothing is less attractive to adult mosquitoes. Tightly woven fabrics give some protection against biting.
  • Citronella and “Avon Skin So Soft” can be used for short periods of relief. Some naphthalene products (such as “Mosquito Beater”) can be broadcast in yards for temporary relief from adult mosquitoes.
  • Adult mosquitoes rest in shrubbery and other shaded areas during the day. These areas can be treated with approved insecticides. Foggers for flying insects can also be used, but will provide only short-term relief. Various aerosol insecticides are available for controlling mosquitoes indoors.


DEET is considered the most effective mosquito repellent. There is concern about undesirable side effects on young children and others who might be unusually sensitive to this chemical. Side effects have been associated mostly with heavy use to avoid transmission of Lyme disease by ticks. The risk must be balanced against the benefits provided by its insect and tick repellency. The Environmental Protection Agency has issued precautions for DEET use:

  • Apply only to exposed skin and clothing, not to skin under clothes.
  • Avoid frequent reapplication or skin saturation.
  • Do not apply to cuts, wounds or irritated skin.
  • Keep away from eyes and mouth.
  • Do not apply to hands of young children.
  • For children, use products with concentrations less than 20 percent.
  • Do not spray directly over face.
  • Avoid breathing DEET aerosol sprays.
  • Wash treated skin and clothing after returning indoors.


Moths attack stored grain products or household foodstuffs. Once established in food, insect populations can increase and infest vulnerable material throughout the home, apartment, or storage area. Some adult moths do fly into the home through open doors or windows, but most are carried inside from outdoor storage or in packaged goods or groceries.

Everyone’s home is vulnerable. However, those who do not store food properly have the greatest problems. Spilled or exposed foods attract the insects and increase the chance of infestation. Foods that are not tightly sealed, especially those maintained for long periods of time, are particularly susceptible to infestation.
The Indianmeal moth and the Mediterranean flour moth are the most prevalent meal moths which infest foodstuffs in Washington. Several other moths that are found occasionally in foodstuffs include the meal moth, the whiteshouldered house moth, and the brown house moth.

Moth Larva

The adult Indianmeal moth, Plodia interpunctella, has a wingspan of about 1/2 to 3/4 -inch. The tips or outer half of the wings are reddish brown or “coppery,” while the basal portions are grayish-white. The larvae are usually off-white but can be pink, yellow, greenish, or brownish. At maturity the larvae are about 1/2 -inch long.
The adult female can lay several dozen to several hundred eggs. The larval stage may last from a few weeks to 9 or 10 months, depending on temperature. The larvae, which spin a great deal of webbing while they are feeding and maturing, are usually found in or near silk tubes. When ready to pupate, larvae leave their tubes to spin a cocoon. They often migrate a considerable distance from their food source while searching for a pupation site, and are found on walls, countertops, and ceilings. This is especially true when infestations are heavy. There can be four to nine generations per year, depending on the food supply and house temperature.
The larval stage is the feeding or “pest” stage. Indianmeal moth larvae appear in grain, cereal and grain products, dried fruit, dog food, candy, dried milk, and many other foodstuffs.

Mediterranean Flour Moth

The Mediterranean flour moth, Anagasta kuehniella, has a wingspan of about one inch. Forewings are grayish with dark zigzag lines; the hindwings are off-white. This moth is most easily recognized by its characteristic resting pose. The moth raises the front of the body, giving the wings a distinct downward slope. The tip of the abdomen protrudes up between the wings. Larvae are white to whitish-pink and about 1/2b -inch long at maturity.

The adult female can lay several hundred eggs. The larval stage normally lasts about 40 days, but can last considerably longer at cooler than optimal temperatures. Under favorable conditions, four to five generations hatch annually. Larvae spin a great deal of webbing on or near their food, as does the Indianmeal moth. These larvae, too, live in silk tubes. Mediterranean flour moth larvae pupate in silken cocoons in clean flour or other food, away from infested material. Mediterranean flour moth larvae generally feed on the same materials as the Indianmeal moth


The adult female meal moth lays about 200—400 eggs. The larval stage sometimes takes as little as 6 weeks. Larvae spin tough silk tubes that are coated or mixed with food particles; they stay in these tubes and feed from the open ends. When fully developed, the larvae leave these tubes and spin silken cocoons in which they pupate.

The larvae of this moth species feed on a variety of grain products. They are generally a problem on food products that are in poor condition, moist, or stored in damp places.

Whiteshouldered House Moth

The whiteshouldered house moth, Endrosis sarcitrella, is not common in household products but is found occasionally, and thus deserves mention. The adults are quite distinctive, having grayish-white wings with dark spots and a “shoulder” area that is bright white. This white shoulder becomes dingy as the adults age. Adults are roughly the same size as meal moths. Larvae are white with brown heads and are about 1/3 -inch inch long at maturity. Larvae feed on grain products, wool or other protein-based carpets, corks, dry seeds, fungi on trees, on rubbish in bird nests, and on other foodstuffs or organic debris which has accumulated undisturbed.
Brown House Moth

The brown house moth, Hofmannophila pseudospretella, is about as common as the whiteshouldered moth. The bronze-brown adult has dark spots on the forewings and is slightly larger than the whiteshouldered moth. Larvae, white with tan heads, are about 1/4 -inch long at maturity. Larvae feed in grain products, furs, paper, carpets, insect collections, dried fruits, and on a variety of other stored products.


Color: Dark gray
Legs: Six
Shape: Small oval
Size: 1/4 of an inch
Antennae: Yes
Flight: Yes

House flies get their name from being the most common fly found around homes. Adult house flies can grow to one-quarter of an inch long and usually live between 15 and 25 days.

They are only able to feed on liquids but have the ability to turn many solid foods into a liquid for them to eat. House flies taste with their feet, which are 10 million times more sensitive to sugar than the human tongue.
House flies tend to stay within 1-2 miles of where they were born; however, they have been known to migrate up to 20 miles to find food.

These insects have been known to carry over 100 different kinds of disease-causing germs, which makes them very bad house guests.

Pests No Summer Picnic; Send Them Packing

“Filth flies” are aptly named. They breed in filth such as moist or decaying organic matter or excrement, and they feed by “spitting out” saliva and former stomach contents onto their intended next meal. After a few seconds, they suck up the fluid they spit out, along with anything it might have dissolved.

Not a pretty sight. But what’s worse is that they spread serious diseases.

Filth flies love to invade our homes during the warm summer months, along with other unwanted pests such as silverfish, millipedes and centipedes, honey bees, skunks and bats— although hopefully not all at once.

No, you don’t want them around to ruin an otherwise pleasant summer.

“These pests can make your fun in the sun a terrible memory,” says Mark Lacey, director of technical and field services for the National Pest Management Association (NPMA), a trade group representing professional pest control companies in the U.S. and around the world.
“They don’t really cause significant damage to your house or business, but will cause damage to your daily activities,” he adds. “For instance, it’s very easy for filth flies to transmit diseases to humans.”

Filth flies – there are about 200 species of them – have been proven to spread more than 65 kinds of human diseases, including leprosy, typhoid, E. coli, cholera, polio, TB, “Staph,” and several kinds of food poisoning.

Problems with humans arise when a fly feeds on some filth, such as dung or garbage, then a few seconds later lands on our plate or sandwich intent on eating the same morsel we plan to eat. Both the habit of regurgitating some of their stomach contents when they feed, and their hairy bodies, make it easy for filth flies to transmit pathogens to humans.

Lacey says summertime “panic calls” to pest control operators are not unusual due to honeybees or filth flies in a porch area just hours before guests are to arrive. Or the discovery of bats in the attic or a skunk or two under decks and in crawl spaces.

Sanitation and mechanical controls have the greatest long-term effect on reducing filth fly populations.

“As always,” Lacey advises, “homeowners and building managers should leave the control of pests to the professional pest control company. Call them at the first sign of a problem to avoid more difficult and costly control later.”

In an integrated pest management approach, the five basic steps taken for unwanted pests are: inspection, identification, the establishment of threshold levels, the employment of two or more control measures, and the evaluation of effectiveness.

Biologists have identified 925 species of the scary-looking bat, one quarter of all known mammal species. The oldest bat fossils are 50 million years old, and paleontologists assume bats had been flying around for a few million years before that.

The bat most Americans probably know best in the summer is the little brown bat, which roosts in attics and barns and prowls for insects at twilight. Although their eyesight is better than most people think, bats routinely depend on their sonar-like location system to hunt flying insects.

Medical concerns about bats are mainly the very small, but real, risk of rabies, which is found in less than 1% of the bat population.
The main situation in which humans are at any risk are when the bat is either sick or injured and falls down within a human occupied area or at least to within a human’s reach.

Control of bats, within the continental U.S. and similar temperate regions, is mainly a combination of removal followed by exclusion. As with other unwanted summertime pests, if you have a bat problem, contact your local licensed and professionally trained pest control professional.
Far less complex than bats, silverfish and their close relatives, firebrats, are small, wingless tear-drop-shaped insects generally covered with, respectively, grayish or brownish scales.

They hide in cracks during the daytime and become active after dark. They survive best in high relative humidity and at the higher temperatures of summer. Most feed on starches, sugars, and proteins they can get from book bindings, glazed paper, or similar sources, including dead insects.
In the home, they may severely damage older books, papers, or other sweet or starchy materials in warm, moist, dark areas. They are often introduced into a home within cardboard or other paper products.

Another summer pest, millipedes, are sometimes called “thousand leggers” because they have 30 to 90 pairs of legs. They’re not really insects, but they can be pests. Their close cousins, centipedes, have less legs. Most common centipedes rarely grow beyond a few inches but can grow up to six inches, which will scare young children and adults alike. Millipedes can grow up to about four inches long. You don’t want them around either.
While honey bees are among the most beneficial insects, they can be pests when they end up in our living space after they build hives in walls or in nearby bushes.

Problem is, honey bees can sting, and some people react violently. Worse, the much-publicized Africanized honey bees, or “killer bees,” have now reached warm areas of the country and are moving further north each year.

By midsummer, honey bees reach very high populations. Interiors should not be fogged if honey bees are found because robber bees may reoccupy the hive, thus perpetuating the bee problem. Instead, a pest control company should be called to alleviate the problem with maximum care and minimal risk to the occupants.


Pets benefit us in many ways, but they are also a breeding site for uninvited fleas. Fleas thrive during warm, muggy summers. If you allow your pet access to both the house and the yard, you should be resigned to the fact that fleas will probably be a problem. Eradicating fleas is only wishful thinking, but flea control is possible. The secret lies in understanding the flea’s life cycle and using an integrated control program.


Adult fleas are wingless, brown to black insects about 1/16 inch long. Fleas mate on the pet, and both sexes bite. After each blood meal, the female usually lays four to eight eggs. Over her lifetime, a female may lay more than 400 eggs. Flea eggs are smooth, whitish and oval and readily fall from the pet to the floor or ground.

Depending on temperature and humidity, flea eggs hatch in one to 10 days. Newly hatched fleas are minute, slender, whitish, wormlike larvae (immature forms). The larvae avoid light, burrowing into carpets, cracks or, if outdoors, soil. The larvae feed on small particles of animal or plant debris and adult flea feces until they achieve full growth. Larval development may require as little as five days but may be extended for up to three weeks, depending on food and environmental conditions.

Next, the larvae spin silken cocoons. These are hard to see because fleas incorporate nearby debris into the cocoon. In the cocoon, the flea larva develops into a pupa (nonfeeding immature stage) and then an adult. The cocoon protects the developing flea from insecticides. Fleas can stay in the cocoon for periods ranging from less than a week to more than four months.

Adult fleas emerge from their cocoons after a physical disturbance or in the presence of warm-blooded animals. This is why vacationers often return to find their homes overrun by fleas. The adult fleas remain in their cocoons when the house is quiet, emerging hungrily all at once when the family returns. The flea’s ability to stay in the protective cocoon so long is one of the reasons an integrated control program is needed.


A control program should be followed in the order outlined below. If possible, this four-step program should be completed in one day.

1. Treat the pet. Check with a veterinarian for the treatment that is best for your animal. Combing your pet with a comb designed to collect fleas can remove many of these parasites from your animal. In addition, a 10-minute, warm, soapy bath will kill most of the fleas on the animal. If just soap and water is not working, you can try pet shampoos containing insecticides such as carbaryl (Sevin), permethrin or pyrethrins. Shampoos do not provide long-term control.

Insecticide sprays are another control alternative. Some sprays for pets contain a flea-like hormone called methoprene. Methoprene disrupts the breeding cycle of adult fleas feeding on an animal. Other new, effective pet treatment products include spot applications (using imidacloprid or fipronil) or oral pills (using lufenuron). These new products are for long-term treatments and are available from veterinarians.

2. Vacuum the house. Before any insecticides are sprayed, vacuum the floors, carpet, furniture and any other areas to which the pet has access. Wash pet bedding. Light traps can also be use to catch adult fleas and evaluate areas where flea numbers are high. These traps are available at many discount stores.

When vacuuming, use a heavy-duty household or commercial vacuum cleaner. In some situations, you may want to have the carpets professionally cleaned. Vacuuming carpets with a beater-bar brush can remove a quarter of the flea larvae and more than half of the flea eggs. Vacuuming also stimulates the fleas to leave their protective cocoons. It also helps to straighten carpet fibers, enabling insecticides to penetrate more effectively. After cleaning, take the vacuum outside and remove and discard the bag because fleas can sometimes crawl out of the vacuum.

3. Treat indoors. With people and pets out of the house and vacuuming completed, an indoor insecticide application can be made. Many products are available. Flea bombs are perhaps the easiest method, but they are not very effective or efficient because they release insecticide all over the room, not just where the fleas are located.

Spot treatments with sprays directed to the floor areas are usually more effective. Methoprene (Precor) or pyriproxyfen (Demize) can be applied for long-term (6 months) larval control as well.

When treating, make the application to the areas pets frequent. Spot-treat carpets, floor edges and cracks and under furniture near pet areas. It is not necessary to treat the entire carpet or all floor areas. If your pet has access to furniture, treat under the cushions, not on top. After treatment, do not touch treated areas until they are completely dry. Remember, always check the insecticide label for special warnings and use the product ONLY according to the directions.

4. Treat outdoors. The outdoor treatment is the final step. Just as you did inside the house, make outdoor insecticide applications to areas where the pet spends most of its time and where it enters the house. Remove pet watering and food containers first. Also, mow any grass and collect the clippings before treating. In areas where there is excessive debris or litter, you may want to increase the volume of water in a spray without increasing the amount of insecticide. This can help get the insecticide into the debris where fleas are hiding. If you use this method, be very careful not to contaminate nontarget sites. Common outdoor insecticide sprays for fleas include carbaryl (Sevin), permethrin (Spectracide Bug Stop Insect Control Concentrate), esfenvalerate (Ortho Bug-B-Gon Garden & Landscape Insect Killer Concentrate), and cyfluthrin (Bayer Advanced Garden Power Force Multi-Insect Killer Concentrate).

It may be necessary to repeat steps 2 to 4 after three weeks before good control is obtained. Fleas in cocoons are very difficult to control with insecticides, and several weeks are usually required for all individuals to complete development and emerge as adults. The hopping activity of the adult allows the flea to come in contact with the insecticides.

Patience is required, but, if all control attempts fail, you need to call a licensed pest control professional. These experienced professionals have access to better application equipment than homeowners and to restricted-use insecticides to help combat fleas.


The European earwig is the most common of the species. It is an elongated, flat insect, reddish-brown to black in color, and 1/2 to 1 1/4 inches in length. The earwig is easily identified by forceps-like appendages (cerci) found at the base of its abdomen. These forceps are used primarily for defense and during courtship. The name “earwig” originated from the widespread superstition that the insects purposely crawl into the ears of sleeping persons and bore into their brains. In fact, other than an occasional pinch, earwigs can’t harm people.

Earwigs are primarily scavengers of dead insects and rotted plant materials but may also feed on live plants. They are a natural enemy of some mites and aphids. Earwigs can become a problem in the garden, feeding on the roots and leaves of flowers, vegetables and shrubs. Common targets include marigolds, dahlias, zinnias, roses, lettuce, and strawberries. They may also feed on corn tassels and blossoms, reducing kernel set. Plants defoliated overnight, in the absence of pests in daylight or the telltale signs (slimy trails) of slugs, may have been attacked by earwigs.

Earwigs are most common in the summer and most active at night. During the day they usually find shelter in dark, moist places beneath stones, boards, sidewalks, debris or in the soil. Since they multiply fairly quickly, an infestation can number in the thousands

When dry weather sends them in search of moisture, earwigs can become an indoor pest as well. Here they will seek shelter under rugs, cushions, and baseboards, and in dark, damp crevices, especially in basements. After entering houses, they feed on sweet, oily or greasy foods or houseplants.


  • For best control indoors, one must first control earwigs outdoors. Eliminate damp, moist conditions in crawl spaces under houses, around faucets, around air-conditioning units and along house foundations.
  • Create a clean, dry border using gravel or stone immediately around the foundation wall. Rain gutters and spouts should carry water away from the house foundation.
  • Eliminate refuges such as ivy, weeds, piles of yard debris and leaves.
  • Check entry points, door thresholds, windows and screens for a tight fit.
  • Caulk cracks and crevices around windows, doors, cables coming into walls, and in the foundation itself.
  • Earwigs are attracted to light. Reduce lighting around doors, windows and other potential entry sites. Use lights that are less attractive to insects such as sodium vapor yellow lights.


  • Encourage natural earwig predators including toads and birds.
  • Construct earwig traps out of shallow tin cans. Fill the cans with a half-inch of vegetable oil and place them in the garden. Empty and refill as needed.
  • Earwigs can also be trapped in cardboard boxes baited with oatmeal or bran. Poke a pencil-sized hole in the sides near the bottom for entry.
  • Effective earwig traps can also be made of rolled newspaper or old hose pieces. Place these tubes near plants at sunset. Empty into a bucket of water each morning.
  • Sweep up or use a vacuum cleaner on earwigs found inside the home. Once inside the home, they will eventually die without treatment


Clover mites as lawn and household pests are usually a late winter/early spring phenomenon. The mites, which develop on grasses and various plants around the foundations of homes, periodically enter buildings in large nuisance numbers. “Walking dust specks” is a frequent description of these nuisance invaders, and they leave a rusty smear when crushed.

Developing clover mites are located in a fairly restricted area of the yard/landscape. This is because clover mites use such vertical surfaces to molt and lay eggs. Warmer, sun-exposed aspects are particularly used by clover mites, which thrive in the dry conditions present in these areas.

During early to midspring, clover mites also may damage turfgrass around building foundations and in other warm, dry areas of a lawn. Feeding damage appears as small, meandering silver streaks (stippling) in the leaves. When mite populations are high, leaves may be extensively injured and die. Areas of grass within 5-10 feet of a building, tree, shrub or other upright object may be totally killed, appearing as light brown, irregular dead patches.

Clover mite injury to turf is commonly mistaken for winter kill and usually is found in the same sunny, dry areas of the lawn where winter drying problems occur.

This year is looking to be well above-average for clover mites. This is due in part to the drop in temperature experienced with the snow/frost last September. The cooler temperatures are important in the hatching of eggs. Clover mites “oversummer” as eggs, becoming dormant when temperatures warm. An early fall storm allows the mites a longer period to develop in the fall, perhaps producing an additional generation. Furthermore, at least along the Front Range, this has been a generally warm, dry and open winter – all conditions that favor population increases of the mites.

The best cultural control of clover mites is to try a little winter watering in those sites where the mites thrive – at the south and west sides of buildings. This can greatly retard populations increasing in spring.

Powderpost Beetles

Lyctus brunneus

Powderpost beetles lay their eggs in cracks of wood and the larvae tunnel into the surface, filling it with a very fine powder-like dust. Powderpost beetles have long, narrow, flat bodies that allow them to easily attack wood surfaces. These beetles are reddish-brown in color.

Color: Reddish brown to black
Legs: Six
Shape: Narrow oval
Size: 1/8 to 1/4″
Antennae: Yes
Flight: Yes

Adult powderpost beetles are very active at night, enjoy flying and are attracted to the light.

Powderpost beetles often attack hardwoods, and can be found in hardwood floors, timbers and crates, antiques and other objects made of hardwood materials.

Some researchers believe that powderpost beetles are second only to termites in the United States in their destructiveness to wood and wood products.

Carpet Beetles

Varied carpet beetles get their name from the rainbow of color on their back surfaces.

Color: Black centers, with white, brown and yellow patches in an irregular arrangement
Legs: Six
Shape: Round
Size: 1/16
Antennae: Yes
Flight: No

Habits: These pests enjoy dining on carpets, woolen fabrics, dead insects, furs, hides, feathers, horns, hair, silk and bones. It can take 249-354 days to three years for varied carpet beetles to grow from an egg to an adult. Carpet beetles often find caches of dog food or other animal products (placed in a wall or other hidden location by other pests) upon which their larva will feed. Removal of these food sources is recommended.

Habitat: Varied carpet beetles are found in homes in attics, Oriental carpets, tapestries and wood-based wall-to-wall carpeting.

Threats: Varied carpet beetles feed on dead insects, but also feed on upholstery and carpet, so they can damage those materials. They can also damage clothing fabric.


Bedbugs get their name because they like to live and feed in beds.

Color: Mahogany to rusty brown; red after a blood meal
Legs: Six
Shape: Flat; broad oval
Size: 1/4
Antennae: Yes
Flight: No

Although bedbugs can dine on any warm-blooded animal, they primarily dine on humans. Bedbugs do not transmit diseases, but their bites can become red, itchy welts.

Vacuum suitcases after returning from a vacation. Check your bedsheets for tell-tale blood spots. Bedbugs are elusive creatures, so it is imperative to seek professional pest control to address an infestation.

This insect has a famous history as a bloodsucker and is named due to its tendency to feed on a bed’s occupants at night. The bed bug primarily attacks humans but can feed on any warm blooded animal such as birds, mice, and pets. The bed bug is found worldwide and probably came to the US from Europe in the 17th century. Bed bugs are mentioned, for example, in medieval European texts and in classical Greek writings back to the time of Aristotle.
Bed Bugs at one time were not as severe as a pest as in the past, due to insecticides and increased sanitation. However, due to the increased use of baits rather than insecticide sprays for ant and cockroach control in the past decade, bed bug infestations have increased. Currently this insect can be a pest wherever sanitary conditions are poor, or if there are birds or mammals nesting on or near a house.

International travel and commerce are thought to facilitate the spread of these insect hitchhikers, because eggs, young, and adult bed bugs are readily transported in luggage, clothing, bedding, and furniture
There are several species of bed bugs, all of which are pests of humans and domestic animals. The Common Bed Bug prefers a human host.

Bed bugs are small, brownish, flattened insects that feed solely on the blood of animals. The common bed bug, Cimex lectularius, is the species most adapted to living with humans. It has done so since ancient times.

Bed bugs are active mainly at night. During the daytime, they prefer to hide close to where people sleep. Their flattened bodies enable them to fit into tiny crevices – especially those associated with mattresses, box springs, bed frames, and headboards. Bed bugs do not have nests like ants or bees, but do tend to congregate in habitual hiding places. Characteristically these areas are marked by dark spotting and staining, which is the dried excrement of the bugs. Also present will be eggs and eggshells, molted skins of maturing nymphs, and the bugs themselves.

Another likely sign of bed bugs is rusty or reddish spots of blood on bed sheets or mattresses. Heavy infestations are sometimes accompanied by a “buggy” or sweetish odor, although such smells are not always apparent.
Bed bugs prefer to hide close to where they feed. However if necessary, they will crawl more than 100 feet to obtain a blood meal. Initial infestations tend to be around beds, but the bugs eventually may become scattered throughout a room, occupying any crevice or protected location. They also can spread to adjacent rooms or apartments

Where They Hide:
Bed bugs can live in almost any crevice or protected location. The most common place to find them is the bed. Bed bugs often hide within seams, tufts, and crevices of the mattress, box spring, bed frame and headboard.

A thorough inspection requires dismantling the bed and standing the components on edge. Things to look for are the bugs themselves, and the light-brown, molted skins of the nymphs. Dark spots of dried bed bug excrement are often present along mattress seams or wherever the bugs have resided. Oftentimes the gauze fabric underlying the box spring must be removed to gain access for inspection and possible treatment. Successful treatment of mattresses and box springs is difficult, however, and infested components may need to be discarded. Cracks and crevices of bed frames should be examined, especially if the frame is wood. (Bed bugs have an affinity for wood and fabric more so than metal or plastic). Headboards secured to walls should also be removed and inspected. In hotels and motels, the area behind the headboard is often the first place that the bugs become established. Bed bugs also hide among items stored under beds

Many areas besides beds, however, can harbor bed bugs. Nightstands and dressers should be emptied and examined inside and out, then tipped over to inspect the woodwork underneath. Oftentimes the bugs will be hiding in cracks, corners, and recesses.

Other common places to find bed bugs include: along and under the edge of wall-to-wall carpeting (especially behind beds and furniture); cracks in wood molding; ceiling-wall junctures; behind wall-mounts, picture frames, switch plates and outlets; under loose wallpaper; amongst clothing stored in closets; and inside clocks, phones, televisions and smoke detectors.
The challenge is to find and treat all places where bugs and eggs may be present. Bed bugs tend to congregate in certain areas, but it is common to find an individual or some eggs scattered here and there. Persistence and a bright flashlight are requisites for success. Inspectors sometimes also inject a pyrethrum-based, “flushing agent” into crevices to help reveal where bugs may be hiding. A thorough treatment of a home, hotel, or apartment may take up to several hours.

The first step of control is to have a professional thoroughly inspect the area. This inspection is required to determine the places where the bed bugs are living. Once the inspection is complete, the pest control professional will determine the proper type of control technique; treat the area and most likely return for a follow up inspection.
Bed bugs are challenging pests to control. They hide in many tiny places, so inspections and treatments must be thorough. In most cases, it will be prudent to enlist the services of a professional pest control firm. Experienced companies know where to look for bed bugs, and have an assortment of management tools at their disposal. Owners and occupants will need to assist the professional in important ways. Affording access for inspection and treatment is essential, and excess clutter should be removed. In some cases, infested mattresses and box springs will need to be discarded. Since bed bugs can disperse throughout a building, it also may be necessary to inspect adjoining rooms and apartments.

Bites and Concerns:
Bed bugs usually bite people at night while they are sleeping. They feed by piercing the skin with an elongated beak through which they withdraw blood. Engorgement takes about three to 10 minutes, yet the person seldom knows they are being bitten. Symptoms thereafter vary with the individual. Some people develop an itchy welt or localized swelling, while others have little or no reaction. Unlike fleabites that occur mainly around the ankles, bed bugs feed on any bare skin exposed while sleeping (face, neck, shoulders, arms, hands, etc.). The welts and itching are often attributed to other causes such as mosquitoes. For these reasons, infestations may go a long time unnoticed, and can become quite large before being detected. Conversely, it is important to recognize that not all bites or bite-like reactions are due to bed bugs. Confirmation requires finding and identifying the bugs, themselves. (Other possible sources of irritation are discussed in University of Kentucky entomology fact sheet ENT-58: Invisible Itches: Insect and Non-Insect Causes).

A common concern with bed bugs is whether they transmit diseases. Although bed bugs can harbor pathogens in their bodies, transmission to humans is considered highly unlikely. For this reason, they are not considered a serious disease threat. Their medical significance is mainly limited to the itching and inflammation from their bites. The usual treatment prescribed is topical application of antiseptic or antibiotic creams or lotions to prevent infection.


Ants, particularly field ants (Formica spp.), tend to show a spurt of indoor activity in late winter. Field ants are usually black (sometimes reddish-brown) and nest in soil. Although they do not nest in homes, the nests are often located around the base of foundations. This leads to the foraging of worker ants in homes, looking for food. Such foraging seems to be most common when outdoor sources of food (particularly sugars) are unavailable due to the continued dormancy of plants and continued freezing temperatures. The ant colonies warmed by the heat of the adjacent home become active early and are forced to forage indoors for lack of other foods. Such problems are usually temporary, ending when plants (and the honeydew producing insects they support) begin to actively grow in spring.

Fire Ants

Both Native and Imported fire ants can sting. The Imported Fire ants are very aggressive, their sting can cause reactions anywhere from an irritation and nausea to even more severeeactions in humans. Imported fire ants have been known to repeatedly attack animals that may intrude on their nests. The red imported fire ant is particularly aggressive. These fire ants are known to attack people, plants, and animals, as well as cause damage to homes, buildings, and air-conditioning units, telephone wires. There are two kinds of imported red fire ants; the single queen and multiple queen forms.

Fire ants workers in single queen colonies are territorial, foraging within their territory. Fire ants workers from multiple queen colonies are not territorial, they freely move from one mound to another, which has resulted in a dramatic increase in the number of fire ants mounds per acre. Areas infested with single queen colonies contain 40 to 150 mounds per acre (rarely more than 7 million ants per acre). In areas with multiple queen colonies, there may be 200 or more mounds and
40 million ants per acre.

Imported fire ants build mounds in almost any type of soil, but prefers open, sunny areas such as pastures, parks, lawns, meadows and cultivated fields. Fire ants mounds can reach 18 inches in height, depending on the type of soil. Many times mounds are located in rotting logs and around stumps and trees. Fire ants colonies also can occur in or under buildings. When their mounds are disturbed, the fire ants workers will come out of the ground and sting the intruder very aggressively.

The red imported fire ant can have huge colonies with 300-500,000 workers foraging at distances of 100 yards. Their usual activity is from the spring time through the fall months. During the spring and summer months, the active mounds will send out winged swarmer ants, whose sole job is start new colonies. Sometimes red imported fire ants will nest inside during the winter months under the bathtubs (when on a slab), or next to hot water heater. Southern fire ants will usually nest in loose soil, but at times they can be found in woodwork or masonry. Their nest may be seen as large crevices in the ground that spread out from 2-4 feet.

Fire ants nests can be found under houses, under boards or stones, or in cracks in theconcrete. Fire ants colonies frequently migrate from one site to another. The queen needs only a few workers to start a new colony. The fire ants can develop a new mound several hundred feed away from their previous location almost overnight. Flooding causes colonies to leave their mounds and float until they can reach land to establish a new fire ants mound. Colonies also can migrate to indoor locations.

However, if the colony makes it through this period it can begin to grow. Wingless, non-sexually mature workers are reared which subsequently help expand the colony. After several years, the colony may be well-established and then some resources are put into rearing reproductive forms. These are the winged ants, some females – the potential future queens – and the majority males. Imported fire ants have the the following characteristics:

  • Mounds of loose soil, resembling gopher diggings,
    are found above ground.
  • Fire ants mounds are generally numerous and easily sighted.
  • Worker fire ants are dark, small, highly variable in size,
    aggressive, and sting relentlessly.
  • Fire ants workers have the same body proportions from the tiniest to the largest.
    Head width never exceeds the abdomen width, even in the largest workers.

The total time from egg to adult averages 30 days, workers live up to 180 days, and fire ants queens live two to six years.

The imported fire ant will not only forage for food, such as small
insects, dead animals, and sweet materials such as plant secretions but willkill insects and small animals to feed. Southern fire ants go for a variety of foods including protein, greases and sweet foods.

Flying Ants

Spectacular swarms of flying ants are a common summer phenomenon. Sometimes people will observe winged ants issuing in large numbers, pushed out by the wingless workers, from a colony established between a sidewalk crack or in a small mound. Other times only the winged forms will be seen, aggregating in large numbers around certain prominent points in the landscape.
Some background. Ants are social insects. The colony is established through the initial efforts of a mated “queen”, a sexually mature female. Originally winged, after mating she sheds her wings and the no longer used wing muscles are an important source of nutrients for her during the early stages of colony development. Very, very few queens successfully survive this period and establish a functional colony

However, if the colony makes it through this period it can begin to grow. Wingless, non-sexually mature workers are reared which subsequently help expand the colony. After several years, the colony may be well-established and then some resources are put into rearing reproductive forms. These are the winged ants, some females – the potential future queens – and the majority males.
Periodically, usually following by 3-5 days a heavy rain, the winged reproductive forms emerge from the colony in large swarms. Such swarming behavior is usually synchronized by other nearby colonies so large numbers of winged ants suddenly appear. All mating for the species takes place, often over the course of a single day. The males die and the mated females disperse to attempt establishing a new colony.

One behavior associated with some ants during mating swarms is “hilltopping”. This refers to their aggregation around prominent points of a landscape where they search for mates. A large tree, the chimney of a roof or even a tractor moving across the plains might serve as such an “action site” for swarming winged ants. My favorite hilltopping site was the top of the US West tower in downtown Denver, which annually is the site for millions of harvester ants to aggregate.

One behavior associated with some ants during mating swarms is “hilltopping”. This refers to their aggregation around prominent points of a landscape where they search for mates. A large tree, the chimney of a roof or even a tractor moving across the plains might serve as such an “action site” for swarming winged ants. My favorite hilltopping site was the top of the US West tower in downtown Denver, which annually is the site for millions of harvester ants to aggregate.
Although dramatic, swarming ants pose no harm or risk of increased ant infestation. Those seen emerging from a colony were always there and are in the process of leaving the colony permanently. Mated females amongst aggregating masses similarly disperse from the area.

However, in rare cases winged ants are seen moving into the house. In some cases it is likely that an established colony exists within the home and may need to be treated. Carpenter ants and pharaoh ants are two species that can produce a nest within a building.

Other ants, such as the field ants, commonly nest outdoors next to foundations and may incidentally swarm indoors, working their way indoors through foundation cracks. And harvester ants in the midst of hilltopping behavior may fall down chimneys. In these cases there is not risk of permanent household infestation.

Odorous Ants

Odorous house ants is a native species found throughout the United States. They produce a foul odor when crushed. It smells like a “rotten coconut”.

Odorous house ants workers are about 1/16-1/8″ (2.4-3.25mm)long There body is brown to black.
The antennae have 12 segments.

Females in the odorous house ants nest lays one egg daily. It takes an average of 24 days for the young to reach adulthood. The nest colonies range from 100 to 10,000 ants, but can be driven away by invading Argentine ants.

Odorous house ants forage day and night The nests can occur in a great variety of situations. Inside, odorous house ants usually construct their nests in wall voids especially around hot water pipes and heaters, in crevices in sinks, cupboards, etc. Outside, they are found in exposed soil, usually shallow, often located beneath a board, brick, stone walk, etc.Odorous house ants are most likely to enter buildings when their honeydew supply or sweet supply of food is reduced such as during rainy weather or with leaf fall in the autumn.

Odorous house ants can feed on anything…insects, honeydew, seeds,
plant secretions, but they do prefer sweets. Odorous house ants are extremely fond of honeydew and attend such honeydew-excreting insects as plntlice(aphids), scale insects, mealybugs, etc.


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Insects are very difficult to manage and eradicate on your own. If you need help removing Insects from your home or business, contact Mountain Pest Control, we’re here to help.