Icky Silverfish are Generally Harmless

Source(s): Jim Howell, Ph.D., Entomologist, The University of Georgia

Silverfish. Sounds like something you’d buy in the frozen foods section at a health food store. But in reality, these little insect pests can become a significant nuisance for homeowners, if populations get out of hand.

As their name implies, silverfish are usually silver to gray in color, and their bodies are flat and wingless. The color comes from the tiny silver scales that give the body a metallic sheen. Their bodies are 1/2 to 3/4 inch long and taper carrot-like from head to tail. Two long antennae extend from the head and usually wrap around the body, while from the tail three long, slender “bristles” extend to the rear.

Firebrats are similar insects but lack the silvery sheen. They are brown to gray, with dark spots that give a mottled appearance.


Development time for silverfish from egg to adult varies from three months to three years. Firebrats usually take about four months. Adults may live three more years and will molt throughout their lives, sometimes more than 30 times a year.

Depending on the species, adults lay five to fifty eggs in clutches, in cracks and crevices near food sources. The nymphs look almost identical to adults except they are smaller and white. Because their populations increase very slowly, large numbers indicate there is a longtime infestation.

Silverfish are found almost anywhere in the house but favor moist, warm locations, especially around sinks and other plumbing, and undisturbed storage areas where the humidity is high. They are frequently found in sinks or bathtubs because they fall in while seeking moisture and cannot climb out. Homeowners often see them when they move storage boxes or open a cabinet door.

Firebrats prefer areas of high temperature (90 degrees and above) and high humidity. They are more common in attics and around ovens, furnances, water heaters and hot water pipes. Both silverfish and firebrats are most active at night, and move swiftly, often stopping for short intervals before scurrying on. They move with a wriggling motion like that of swimming fish.

Both silverfish and firebrats are often initially brought into the home in paper, books, food, starched clothing or furniture.


These insects are considered pests primarily because they are a nuisance. They feed on a wide variety of materials, including bookbindings, starch in clothing, linen, dried organic ornaments, wallpaper, paste and glue. Damage is significant, however, only in large infestations over long periods.


Sanitation is a major step in controlling these pests. When storing items, especially fabrics, be sure they are clean and starch-free. Store them in tight-fitting containers and reduce the moisture as much as posibble. Because these pests often reside in wall cavities, keep storage boxes a few inches away from walls and raised off the floor.

Chemical Control

If sanitation alone is not sufficient, various pesticides may be useful in eliminating or reducing these pests. Sprays for ants and roaches in pump sprayers or aerosol cans are usually effective. Recommended pesticides include cyfluthrin, cypermethrin, esfenvalerate and permethrin. Also, boric acid can be puffed into cracks and crevices and loosely around storage areas. It has the advantage of being very low in toxicity and very long-lasting if applied in dry voids where it will remain undisturbed.

Control may not be necessary if populations are low and limited to small areas and if no damage is noticed.

Center Publication Number: 166

Menacing Mice

Source(s): Jim Howell, Ph.D., Entomologist, The University of Georgia

House mice are one of the most troublesome and economically important pests in the United States. They consume food meant for human beings, pets and other animals; contaminate areas with their feces and urine; cause considerable damage to structures and property; and spread numerous diseases.


The house mouse (Mus musculus) is a small, slender, grayish-to-brown rodent having large ears, small black eyes and a slightly pointed nose. A house mouse weighs 1/2 to 4/5 ounce and is approximately 5 to 7 inches long, including the 3- to 4-inch tail. A house mouse lives about one year and reaches sexual maturity in 6 weeks.


House mice are found in and around homes and commercial structures as well as in open fields and agricultural lands. They came to the United States with the early Colonists and rapidly spread across the entire country.

They are generalist feeders but prefer seeds and grain. They also love foods high in fats, sugar and proteins, like bacon, chocolate candies and butter.

Mice are nibblers and though they may eat only about 3 grams of food a day, they destroy much more food than they consume. A single female may have up to five to ten litters a year, each litter having about five to six young. With that in mind, a single fertilized female can result in a large indoor population in a relatively short period of time.

Nests consist of fibrous material like cloth, rags or paper, usually in the form of a ball about 4 to 6 inches in diameter.

Mice are found in virtually any sheltered location. Indoors, they may be in a hole in the woodwork, or beneath some protective cover. Outside, they may nest in animal burrows, in collected plant material or beneath debris. When mice are present in significant numbers, their infestation is announced by a characteristic musty odor.

They are nocturnal and aren’t often seen by the homeowner, but their droppings, black pellets about 1/8 to 1/4 inch long and tapering on both ends, is a sure indication of their presence.


The house mouse is considered one of the most irksome and economically important pests in the United States. It gnaws on electrical wiring and may cause fires or failure to appliances; it pollutes clothes, food, furniture and other items with its droppings and urine; and it can spread disease when its waste products contaminate our food.


The homeowner has a few options, including traps, rodenticides (poisons), and calling a licensed pest control company.

When populations are small, traps are the preferred method. They are less of a hazard for pets and children. and the mice can be removed promptly without the accompanying odor of animals dying in wall spaces and other inaccessible places. Snap traps are readily available at most grocery and hardware stores. Baiting with bacon or peanut butter gives excellent results.

Rodenticides should be used as a last resort because of hazards to children and pets. Extreme care should be taken to position these products in areas inaccessible to other animals and children.

Center Publication Number: 243

Opossum Damage and Control

Source(s): Jim Howell, Ph.D., Entomologist, The University of Georgia

Opossums are found throughout much of the United States and north into parts of Canada. Although these animals are interesting and beneficial in the wild, they can become a nuisance when seeking food or shelter in our homes or other buildings.


The common opossum is a grayish-white animal with a scaly, hairless tail, a triangular shaped head with a pointed snout, and is about the size of a house cat. Males reach a length of 3 feet, including the tail, and average 6 to 12 pounds. Females are smaller and weigh about 4 to 6 pounds. Their frequent “grin” shows 50 sharp teeth, more than any other North American mammal. The opossum is the only marsupial in North America, and females, like kangaroos and koalas, carry their young in a pouch located on the front of the abdomen.


Opossums thrive east of the Rocky Mountains. They are common from Maine to Florida and have been introduced into California. Opossums, like other marsupials, give birth to relatively undeveloped young which climb into the mother’s marsupial pouch. They spend the next two months feeding on mother’s milk before emerging. There are up to three litters a year from January to July, with about six to eight young per litter. When the female leaves the den, the young opossums often ride along on her back. Opossums eat a wide range of foods, including but not limited to carrion (popularly known as road kill), grass, fruits and vegetables, insects, garbage, pet foods, snakes, chickens, and eggs.

Although their first line of defense is to hiss and bare their teeth, as a last resort they may play dead. The popular term “playing possum” comes from the opossum’s habit of dropping to the ground, opening its mouth and remaining motionless for several minutes. Many predators won’t attack a dead animal and will walk away when an opossum plays dead.

Because of their range and dietary preferences, they are sometimes a nuisance to homeowners. Because they readily eat pet foods and cultivated plants, and rumage through garbage cans, they often come into contact with humans and will readily enter dwellings through vent systems or torn screens. They may adopt a household because of the availability of food and will take up residence behind stored items in carports or beneath houses, leaving unsightly droppings along with an unpleasant odor.


Live traps can be used to capture opossums. Cat food, apples or sardines make good bait. Once captured, a problem arises: what to do with the critter? Relocation may work if you are sure you are not creating another problem in the release area. Local ordinances should be checked for restrictions on capture and release efforts. Most counties recognize these creatures as game animals, but local regulations should be consulted before treating them as such.

Center Publication Number: 235

Pesky Fruit Flies

Source(s): Jim Howell, Ph.D., Entomologist, The University of Georgia

If you see small flies or gnats in your kitchen, they are probably fruit flies. Fruit flies can be a problem year round, but are especially common during summer and fall when they are more likely to be attracted to ripe or fermenting fruits and vegetables.

fruit flyIdentification

Fruit flies are small, red-eyed insects about 1/8 inch long, usually tan in front with a black behind. They’re easily identified by their erratic aerial stagger in the vicinity of ripe fruit.


Fruit flies are very common in restaurants, markets and other places, including our homes, where food is allowed to decay and ferment. They are often brought into our homes on previously infested produce but may also fly in through poorly screened windows and open doors. Females deposit eggs on fermenting foods, especially fruits and vegetables, and the developing larvae continue to feed near the surface.

The reproductive potential of these insects is incredible. If left undisturbed, a single female can lay 500 eggs, and the offspring can go from egg to adult in about a week. They have a special affinity for the rapidly fermenting fruits and vegetables, including apples, bananas, peaches squash and melons. However, they may breed in drains, garbage disposals, trash containers and empty cans. There is even a report they can reproduce in a wet mop! All they need is a moist film on a fermenting substance.


Fruit flies may have the ability to contaminate foods with bacteria and other disease producing organisms, and their presence in large numbers can be a major nuisance for the homeowner. The dancing plume of fruit flies that rises up from a bowl of ripening fruit is not a sight you want to see when entertaining guests.


As with many food and pantry-infesting pests, the most important thing is to find the source. Locate all breeding areas and eliminate them. Simply put, throw out the infested fruit or produce. Fail to do so, and the problem will continue and increase, regardless of how many adults that you may kill. After removal of the infested products, remaining fruit flies can be killed with a pyrethrin-based aerosol or other insecticide labeled for indoor use in controlling fruit flies.


The best way to prevent fruit flies is not to allow an infestation to develop. Be aware of fermenting fruits and vegetables. Ripe fruit should be eaten, throw away or refrigerated. Damaged pieces should be discarded. A single piece of fruit left in the back of the closet or fruit juice spilled beneath a cabinet or refrigerator, may be the source for thousands of fruit flies. Also, windows and doors should have tight-fitting screens to keep adult fruit flies from entering the home.

Center Publication Number: 246

Eastern Tent Caterpillar

Source(s): Jim Howell, Ph.D., Entomologist, The University of Georgia

Ah, the harbingers of Spring have arrived! The Atlanta Braves are playing ball, azaleas and dogwoods are blooming, robins are on the windowsill – and tent caterpillar nests are appearing in our wild cherry trees.

Eastern tent caterpillar eggs are timed to hatch when the cherry buds unfurl, and their rapidly growing silken nests make them an excellent sign for the warming that is just around the corner.


Older larvae are generally black, with long brown hair and a white stripe down the middle of their backs. Along the midline is a row of blue spots with brown and yellow lines. At maturity, the caterpillars may reach a length of 2 1/2 inches. Adults are reddish-brown, with two white oblique stripes on each forewing.


Adult moths emerge in May and early June and lay egg masses that resemble chocolate-colored collars that encircle the smaller limbs of their host. Each egg mass is about 1 inch long. Eggs overwinter and hatch in mid-March of the following year, at the same time the cherry buds unfurl. The appearance of new, tender leaves is like the ringing of a dinner bell.

From each case, several hundred tiny feeding machines emerge, and for four to six weeks they hungrily strip the trees of their leaves. The larvae are gregarious and upon hatching they gather in the forks of the limbs. Usually one of these tents or “colonies” is made of insects hatching from several different egg masses.

From this mass of silk, the developing larvae move outward to feed on developing leaves. They produce a fine thread of silk that is laid down wherever they crawl, and in a few days, well-defined pathways can be seen leading from the nest to various feeding sites in the tree.

Most of the larvae return to the tent at night or during rainy weather and the nest gradually becomes larger and larger as silk accumulates. Most of the leaf is consumed, leaving only the mid-vein.

About three weeks later, the adult moths emerge, mate and lay their eggs, which stay on the trees until the following spring, when the process begins again.

Though the nests are most commonly seen in the forks of wild cherries, this pest can be found in other ornamental, shade and fruit trees, especially apples. While not a serious pest in the natural forest, this insect can be a blight to homeowners because the infestations reduce the beauty and esthetic value of shade trees and other hardwoods in the landscape.


The large silken masses are unsightly in the forks of trees. In addition, about four to six weeks after hatching, full-grown larvae will crawl away from their nests and accumulate on the sides of homes, on driveways and sidewalks and on various woody ornamentals in search of pupation sites.

At this time, homeowners express concern about possible damage to other plants. But by now, the larvae are finished with their feeding and will do no damage to plants on which they are found. Their white cocoons are usually spun on tree trunks or nearby objects.

The caterpillars are primarily a nuisance and do not usually pose a danger to the overall health of larger, well-established tree. Young fruit and ornamental trees may be damaged, however.

The larvae finish their feeding at a time of vigorous leafing activity, and though the trees are often stripped of their leaves, they usually produce a new flush of foliage within two or three weeks.


Usually, no controls are necessary. But should caterpillars attack young trees and for aesthetic preservation, the nests, along with their accompanying larvae, can be removed and destroyed. In addition, the egg masses can be clipped from the limbs in late June to prevent nests from developing the following spring. For chemical controls, explore the “Georgia Pest Management Handbook“.

Center Publication Number: 176

Don’t Move Mealybugs Inside

Source(s): Jim Howell, Ph.D., Entomologist, The University of Georgia

Citrus Mealybugs

Winter approaches, and with the onset of cooler temperatures, we can finally forget about insect pests until next year. Right? Time for the bugs to either die from the cold, or find some protected retreat until Spring. Or is it?

Don't Move Mealybugs Inside

Some insects thrive indoors and love to take up residence in our homes during the winter months. When we bring our frost-sensitive plants inside, we often times bring in insect pests as well. These insect pests are more than ready to enjoy the protection that our homes provide. One of the most common plant hitchhikers is the citrus mealybug.


Adult female citrus mealybugs are oval, segmented and about 1/5 inch long, with white, waxy secretions, giving the insects a “mealy” appearance as if covered with fine flour. They also have waxy lateral and terminal filaments of various lengths. Under a hand lens these little sapsuckers look like they’re freshly battered, rolled in flour and ready for the skillet! This “mealy” covering protects the insects from excessive heat and water loss. Mealybugs are usually mobile and may move around very slowly on the stems and leaves of their host plants.

Life History

Citrus mealybugs lay their eggs in a white powdery/waxy mass. An individual may deposit 300 to 600 eggs in this mass and will die soon after the eggs are laid. Time to hatch will vary with temperature, but indoors in a warm environment, the eggs may hatch in as little as one to two weeks. Immature stages develop their powdery covering soon after hatching. They move around on the plant before settling down and are especially active in warm, dry weather. Then, they insert their mouthparts and suck plant juices from their host plant. Population size varies, but under proper conditions, mealybugs can accumulate in large numbers and may kill the plant. This species thrives on a variety of hosts, including but not limited to, African violets, amaryllis, begonias, citrus, coleus, cyclamen, dahlias, dracaenas, ferns, ficus, poinsettias and philodendrons.


Mealybugs damage their host plants in several ways. Removing sap, or plant juices, weakens the host plant, and the injection of a toxin found in the mealy bug’s saliva is responsible for distortion and yellowing, as well as flower and fruit drop. Mealybugs also produce large amounts of honeydew – a sugary excrement that coats leaves, stems, flowers and fruit. This sugary coating may cause formation of a black sooty mold that degrades the plant’s appearance, and in large quantities can inhibit photosynthesis.


Mealybugs are difficult to control. On houseplants, remove mealybugs with a cotton swab dipped in alcohol or fingernail polish remover. Also, you can wash the insects off in a steady stream of water or wipe them away with a wet cloth. Monitor your plants for a few weeks in case some were missed. Recommended insecticides can also be used to eliminate mealybug infestations; however, heavily infested plants should be discarded.

Resource(s): Insect Pests of Ornamental Plants

Center Publication Number: 231

Raccoon Damage and Control

Source(s): Jim Howell, Ph.D., Entomologist, The University of Georgia

Many areas considered to be in the “country” just a few years ago are now more urban. Because of this transition in land use, raccoons and other animals once called wildlife may now be considered backyard pests.



Raccoons are stocky, 2 to 3 feet long and usually 10 to 30 pounds. They are grizzled gray, with a bushy tail marked by alternating gray and black rings. The black “mask” across the face is the trademark feature by which most of us know them.



Though raccoons prefer a wooded habitat that includes water – lakes, rivers, marshes – they are amazingly adaptable, and many have found a relatively easy life in the urban and suburban environments of our cities and towns. In more forested areas, raccoons commonly den in hollowed trees, ground burrows or under brush piles. But in the urban environment, they have moved into our chimneys, attics and wall spaces.

Raccoons are omnivores, eating both plant and animal foods. Plant foods include berries, corn, fruit, nuts and vegetables. They are opportunistic hunters and feed on insects, grubs, crayfish, frogs, fish, bird eggs, nestlings, squirrels, rats and other small animals they can catch. They are most active at night, but sometimes they forage for food during the day.

Raccoons usually breed in February and March and bear one annual litter of three to five kits in April and May, though late matings can result in births as late as August. The home range varies from one to 20 square miles, depending on food or mate availability. They do not hibernate but may “hole up” in severe weather.


Raccoons can be a serious nuisance problem when they decide to enter our homes, using chimneys, attics or wall spaces as a replacement den instead of a hollow tree. For their size they are powerful animals and can rip off boards and shingles in search of a retreat. Raccoons are amazingly dexterous, too. In urban areas, they routinely open garbage cans and dump the contents in search of food. They often dig up sod in search of insects and earthworms, thus damaging our lawns. They may feast on unpicked vegetables as well, thereby destroying our gardens. Raccoons can even injure pets sometimes, such as cats and small dogs. Lastly, raccoons are a major wildlife reservoir for rabies in the United States.


First of all, do not feed wild animals. Depending on your location, this may even be a crime. This activity encourages the animals to stay in the area and often results in their invading our homes. Bring pet foods in at night and store in a garage or other secure place. Place garbage in metal cans with tops that can be secured until pickup. Sprinkle soap flakes on the lawn and water in to help deter raccoons from digging up the lawn. Sprinkle diluted Tobasco over the vegetables in your garden to help deter raccoons from damaging your plants.

Inside Nuisance

If a raccoon has entered through a pet door, close off all other doors to the house. The animal may leave the same way it came in. If you hear noises in your chimney – whines, snarls, whimpers, etc., especially in February and May, it may well be a nest of raccoons. Do not start a fire in the fireplace in hopes of driving them out. The female will leave and the young will be left. The young raccoons can not escape. For chimney, attic or wall space removal, contact a licensed professional. Racccoons are considered game animals in many states and trapping them is illegal, if out of season and without proper permits. After the animal has been safely removed, take immediate steps to seal any possible entry sites.

Center Publication Number: 233

The Hercules Beetle, A Real Bruiser of a Bug

Source(s): Jim Howell, Ph.D., Entomologist, The University of Georgia

What do the words elephant, rhinoceros, ox and Hercules have in common? Of course, they are all terms for something bulky and powerful. They’re also common names for a group of large, robust beetles in the family Scarabiidae.



Rhinoceros beetles include the largest beetles in the world, and they’re aptly named, because males have a characteristic horn (females have no horn) that extends forward from its pronotum (the body section behind the head). The gargantuan Hercules beetle – Dynastes hercules, from the rain forests of South America – can reach a length of 8 inches. Its been estimated that some species can lift 850 times their own weight – truly a Herculean feat.

Georgia has several species, but the most common is the eastern Hercules beetle, Dynastes tityus. Specimens range from 1.5 to 2.5 inches long and are usually olive green to tan, with black splotches on the back. The large pronotal horn that extends forward in the males almost meets another horn projecting upward from the head. Adults of this species are the largest beetles in the eastern United States.

Biology and Distribution

The eastern Hercules beetle ranges from southeastern New York to Florida and from Illinois and Indiana to the Gulf of Mexico. Egg laying occurs in the summer, and development may take two to three years. Adults emerge in June and July. Adults are thought to feed mostly on rotten fruits and sap, and the larvae on rotting wood, but relatively little is known of their habits.

This species emits a foul odor to discourage predators but often falls prey to larger insectivores like crows and owls. Adult beetles are attracted to light and are often seen at night around streetlights and the large mercury vapor lamps in shopping centers.


Rhinoceros beetles do little or no economic damage. They are, instead, a lovely sight to see in our gardens (remember, beauty is in the eye of the beholder). Though these insects may appear foreboding and perhaps even terrifying, they are completely harmless and cannot bite or sting – and, unlike their African namesakes, they cannot gouge you with their horns.

Center Publication Number: 210

Cats and Allergies

Source(s): Jim Howell, Ph.D., Entomologist, The University of Georgia

Cat allergy is by far the most common pet allergy. Five percent to 10% of the general population have a distinct cat allergy and up to 40% of asthmatics are sensitive to cats.


Contrary to popular belief, the allergy-causing substance from cats is not cat hair. Although individual cats may produce varying amounts of allergen, there is no relationship between the pet’s hair length and allergen production, and although some will argue the point, there is no such thing as a nonallergic breed.

The cat allergen is found primarily in flakes of cat skin and salivia. Male cats produce more of the allergen than females. It is produced in the animal’s salivary glands and the sebaceous glands in the skin, and because cats love to groom, they deposit this protein on their fur when they lick themselves.

These microscopic allergen particles can remain airborne for a long time. They can be easily inhaled into the nose and lungs, producing an allergic response. Mattresses, sofas and carpets can contain significant allergen particles up to six months after the animal has been removed. These particles also accumulate on walls.


People suffering a serious cat allergy will exhibit almost immediate rhinoconjunctivitis and wheezing upon entering a room that contains a cat. Cat allergy is a common trigger for atopic eczema, an itching , scaling or thickening of the skin. Perennial allergic rhinitis – chronic or recurent sneezing and/or runny nose – is like having year-round hay fever or a permanent cold. It’s important to know that allergies have an immediate (within one hour) and delayed (two hours or longer) component. An asthmatic, for example, might notice a worsening of his or her condition the day after exposure. An asthmatic may sometimes get no acute flareup and will assume he or she doesn’t have a cat allergy. But it is very possible there is ongoing chronic inflammation in the lungs due to ongoing cat exposure.

What To Do

If you have a cat allergy, the best thing to do, of course, is to remove the cat. But many allergic cat owners would rather suffer the consequences than get rid of their pet. If so, try the following:

  • Remove airborne particles as much as possible. Use an air purifier with a HEPA filter.
  • Keep cats out of bedrooms or other spaces where you spend a lot of time, such as a home office.
  • Vinyl or hardwood floors are preferable to carpets because they hold far less cat allergens.
  • Air out the house. Opening windows and using exhaust fans can increase air exchange and decrease airborne allergens.
  • Use a damp cloth to clean walls and furniture.
  • Use a dust or face mask when brushing or cleaning your cat.


  • Lynwood Blackmon, CEA – DeKalb County.
  • Bobby Wilson, CEA – DeKalb/Fulton Counties, The University of Georgia College of Agricultural and Environmental Sciences.

Center Publication Number: 240

Brown Bats

Source(s): Jim Howell, Ph.D., Entomologist, The University of Georgia

Bats are very beneficial creatures that feed on a wide variety of insects, including mosquitoes. Nonetheless, we as homeowners do not want them to establish residence in our attics or the walls of our homes.



Sixteen bat species call Georgia home and all of them are insectivores. The big brown bat is the most common house-infesting species in the Atlanta area and is one of the few that will remain throughout the year. Other species migrate south in the fall.

The big brown bat has broad black ears and thick black wings and is chocolate brown on its back and sides, lighter on its belly, and reaches a length of about 4 to 5 inches. Another species, the Brazilian free-tailed bat, is common in the southern part of the state and forms huge colonies in deserted buildings, sometimes numbering in the thousands.


Big brown bats mate in the fall, and their young are born the following May or June. During that time, about 40 to 100 pregnant females roost together in nursery colonies. The young are capable of flying in three to four weeks. This species is largely crepuscular, feeding on mosquitoes and other insects. After an initial evening foray, the bats return to their roost. They feed again later in the night before moving back to the roost, where they will remain during the day. Predators of the big brown bat include rat snakes, the barn owl and the great horned owl.


Bats often roost in attics or other hollow spaces in homes. Bat droppings can build up over time, creating unpleasant odors. They also harbor bat bugs, which can be a problem for humans, especially after the bats have been removed.


The favored method of bat control is exclusion. To be certain all bats are outside the structure, this should be done in the fall, when there are no young. It should also be done after dark, when the bats are out foraging for food. Bat valves are also available that will allow bats to leave, but not to enter.

Building bat boxes is a good way to keep bats out of your house but to keep them in the area.

Center Publication Number:227