Abundance of House Flies

As we venture in and out of buildings be might have a piggy-backer, the house fly (Musca domestica) joining us indoors. This fly is not only a big nuisance insect, but it can sometimes carry other organisms that can cause diseases in humans and domestic animals. This makes suppressing house fly populations very important.
House flies are ¼-inches in length, light grey in color and have four longitudinal black stripes on their thorax. They also have a pair of large, red-brown compound eyes and sponging mouthparts, so they are non-biting flies.
Adult house flies live up to three weeks and are active during warmer weather. The adult female flies deposit eggs in clusters of 50 to 100 within a variety of moist, decomposing organic substrates including animal manure, accumulated grass clippings, garbage, spilled food and animal feed. The eggs usually hatch into larvae within 12 hours. The larvae then feed on the decomposing organic material as they continue to grow in size. Then the larvae will stop feeding and migrate to drier substrates to pupate. Adult flies will emerge within three days to four weeks, depending on the temperature.

Some Suggestions for Control:

Non-Chemical Control Options:

Frequently clean surfaces and properly dispose of food and other organic materials within a sealed garbage bag. Garbage containers should be closed and placed away from doors to prevent fly breeding and entering buildings. The garbage container should be cleaned a couple of times a month with soap and water to decrease amount of accumulated organic matter. Make sure that windows screens and screen doors do not have holes in order to minimize house fly access. Retail buildings can install air curtains above exterior doors to make it harder for flies to enter. Several types of traps are available that do not contain toxic chemicals, such as sticky traps and ultra-violet light traps. All traps need to be placed at least 5 feet away from food processing areas to avoid contamination. Sticky traps need to be replaced frequently as they loose their effectiveness with time. In addition, a fly swatter can be used to kill the occasional invader!

Some Chemical Control Options:

Chemical control should not be the only control option used, since the overuse of insecticides may lead to secondary problems such as insecticide resistance and increased allergies and other health problems. Some house fly insecticides are sold as aerosol sprays or bait formulations and can be applied to such areas as dumpsters. Several insecticidal sprays labeled for house fly control in and around buildings contain permethrin, tetramethrin or resmethrin. Fly baits are usually sugar-based and contain a compound that attracts the adult flies. The flies that feed on these baits are then killed after injesting the insecticide.

Photo of house flies, Musca domestica Linnaeus (Diptera: Muscidae), mating. Photo by Dr. Bart Drees, Professor and Extension Entomologist.

Summer Means a Time for Fleas

The most common type of flea in Texas is the cat flea, Ctenocephalides felis (Bouché). However, there are other flea species in Texas, including the dog flea, Ctenocephalides canis (Curtis), and the oriental rat flea, Xenopsylla cheopis (Rothschild). All of these fleas are around 1/8 inches in length, dark brown in color and have a wingless, flattened body.
Flea eggs are laid on a furred host after consuming the host’s blood. The white round eggs fall off of the host onto the ground in the area where the host spends time and rests. Whitish, legless larvae hatch from eggs in 2 to 3 weeks. The larvae develop in 9 to 15 days under optimum conditions. Fully developed larvae will then pupate by spinning a cocoon of silk that becomes covered with soil particles and debris. This protects the pupa and makes them hard to detect. The pupal stage lasts from 7 days up to a year before the adults emerge. Under optimum temperature and humidity conditions, fleas can complete their lifecycle from egg to adult in 30 to 75 days.
Adult mouthparts are modified for piercing and sucking blood, so they can bite multiple times. Not only are flea bites irritating due to an itchy reaction, but fleas can also transmit diseases such as murine typhus.
Sometimes buildings can become infested with fleas even when there are no pets around. Other animals such as bats, roof rats, squirrels and raccoons commonly have fleas and may bring them into structures. The building should be inspected and all openings should be sealed so wildlife can not enter.

Some Non-Chemical Control Suggestions:
Change pet bedding regularly and vacuum thoroughly. Vacuum under furniture, cushions, chairs, beds, and along walls. Make sure to discard vacuum cleaner bags at least once a week, since fleas can continue to develop inside vacuum cleaner bags.

Some Chemical Control Suggestions:

Treat your pets. Treatments are available as sprays, spot-ons, pills or food additives for pets. With all products, read and follow label directions carefully. Products designed for use on adult dogs should not be used on puppies or cats, unless specified on the label.

Treating homes. The pet’s living area should be treated at the same time that the pet is treated. This will hopefully prevent re-infestation of the pet. Citrus sprays containing d-limonene is one suggestion that can be applied to rugs, carpeting and pet bedding. Also, insect growth regulators such as methoprene and pyriproxyfen can be used indoors. Methoprene is unstable in sunlight so it is an effective indoor treatment. However pyriproxyfen sprays, can be applied both indoors and outdoors. Outdoors, treat areas where pets spend most of their time, such as bedding areas or under shade trees.

****Remember to inspect your pet regularly for fleas and carefully follow the label directions on the insecticide products!



Lifecycle of a Flea. Photo by: Bart Drees, Professor and Extension Entomologist, Texas A&M University.

Tarantula Hawks On the Loose!

Tarantula hawks (Pepsis sp.) are most active in the summer, during the day, although they avoid the highest temperatures. They are one of the largest species of wasps in Texas. They are 1 ½ inches in length, metallic blue-black in color with red wings. Tarantula hawks are considered generally harmless to humans, since they seldom sting. However they can be provoked, so they should be left alone; their stings are considered to be the most painful of any North American insect.
Tarantula hawks get their common name since they use tarantulas as food for their immature stages. These wasps are found wherever tarantulas are found since tarantulas are needed for the continuation of the wasp’s lifecycle. The female wasps will either enter a tarantula burrow and push out the spider, or attack a male tarantula while he is searching for a mate. She will grab the spider by a leg, flip it over on its back and sting it, or she may approach it from the side to deliver a sting. Once the tarantula is stung, it becomes paralyzed within seconds.
If the female wasp expelled the tarantula from a burrow, she will drag it back into its own burrow and lay a single egg on the spider’s abdomen. Then the burrow will be sealed. If the female wasp stings a male tarantula in search of a mate, the female wasp will excavate a burrow and drag the paralyzed spider inside. Then she will lay her single egg and seal the chamber. Once the egg hatches, the wasp larvae begins to feed on the tarantula and develops within the burrow.
Male tarantula hawks usually perch on taller vegetation or high points, where they wait for newly emerged females, which may be receptive to mating. Both male and female tarantula hawks feed on nectar.

A tarantula hawk, Pepsis sp. (Hymenoptera: Pompilidae). Photo by Bart Drees, Professor and Extension Entomologist, Texas A&M University.

Reminder for Safe Pesticide Practices

It is always important to remind ourselves of proper safety when mixing and applying pesticides. Always keep in mind that just because a chemical may seem like a safe material, when concentrated it will not necessarily be safe or less toxic to humans or other animals! We must do our part to protect ourselves and our environment by reading and following the pesticide label directions!
Personal protection equipment depends on the job and the pesticide label, but some good suggestions are to wear a long sleeved shirt, long pants, waterproof gloves, a wide brimmed hat, waterproof boots, an approved respirator with the right cartridge when mixing dust or wettable powders and safety goggles when applying pesticides.
When mixing pesticides, weigh the material carefully, fill the tank with water until half full, and then add the concentrate while water is swirling. Remember to stand above the fill hole to prevent splashing onto face or eyes. After application, rinse the container three times and pour rinses into a mixing tank.
For application, wait until the pesticide needs to be applied, then read the entire label, and wear full coverage protection required by the label. DO NOT attempt to spray when there are gusting or heavy winds, if rainfall is imminent within 6 hours of spraying or if you are feeling angry and frustrated. Also do not smoke, eat or drink while applying any pesticides.
For pesticide disposal, buy only the amount of pesticide you need for the season. It is important to try to only mix the amount of material needed for the treatment. If there is too much, then apply excess material to labeled site or border row. The improper disposal of pesticide containers can lead to ground water contamination. To prevent ground water contamination, use returnable containers and take them back to the dealer when empty. If non-returnable containers are used, then triple-rinse the containers immediately after use (residue can be difficult to remove after it dries) and pour it into the spray tank. Puncture non-returnable containers and store them in a covered area until they can be taken to a container recycling program or a permitted landfill. Contact the Ag Container Recycling Council at http://www.acrecycle.org for more on a recycling program. If bags are used, shake them out, bind or wrap them to minimize dust, and then take them to a permitted landfill.
In case of spill, remove contaminated clothing and wash chemical from skin with soap and water. Launder contaminated clothing separately from other clothing. Follow recommended cleanup and sanitization procedures printed on the pesticide label. Contain spill with containment soil, soda, or absorbent materials. Use cat litter, clay sawdust, soda ash or absorbent cleaning compound to soak up excess pesticide. Always have someone with you as you apply pesticides, in case of an accident. If symptoms of poisoning arise, seek medical help and take the pesticide label or container with you to the hospital.

Photo of proper safety equipment. Photo by: Bart Drees, Professor and Extension Entomologist, Texas A&M University.

Excess Rain Means Pesky Mosquitoes!

Due to the all of the April and May rainfall in Texas, we are now experiencing a higher population of another pest insect, the mosquito. Mosquitoes are a diverse group of flies that are found worldwide, with about 85 species living in Texas.
Mosquitoes develop through complete metamorphosis with an egg, larva, pupa and adult stage. Mosquito eggs may be laid individually or in clusters on the surface of water or in dry locations that will periodically flood. The eggs hatch into larvae that eat bacteria, fungi and other organic debris in the water. The larvae will develop into pupae, which do not feed. The adult stage will emerge from the water to take flight.
Adult male and female mosquitoes feed on nectar, honeydew and fruit juices. The female mosquito will consume blood in order to develop her eggs. This causes the female mosquitoes to be the most DANGEROUS ANIMAL in the world, since they are capable of transmitting such diseases as Malaria, West Nile Virus, Eastern Equine Encephalitis, and Yellow Fever worldwide.
Some Control Options Outdoors:
The number one way to reduce mosquito populations in your yard is source reduction! Mosquitoes need as little as a bottle cap full of water to complete their lifecycle, so all areas where water collects needs to be emptied or changed weekly. If standing water is eliminated in your backyard, then the overall mosquito population in your area will be reduced.
1) Areas containing water should be changed or emptied weekly, such as wading pools, buckets, bird baths, pet dishes, ponds, boat covers, irrigation systems, and French drains.
2) Holes or depressions in trees should be filled with sand or mortar.
3) Leaky pipes and faucets should be repaired.
4) For standing water that can not be drained, one suggestion is to use mosquito dunks containing Bacillus thuringiensis israelensis (Bti) to kill the mosquito larvae.
Mow tall grasses and reduce the amount of foliage to reduce the resting sites for adult mosquitoes. Insecticides can be applied to trees and shrubs, such as those containing permethrin, in order to kill adult mosquitoes.
Some Options To Prevent Mosquito Bites:
1) Avoid wearing dark colors, since mosquitoes use visual cues to locate hosts.
2) Avoid exercising or yard work in the heat of the day, since mosquitoes are attracted to carbon dioxide and perspiration.
3) Avoid wearing fruity or floral fragrances in perfumes, deodorants, hair products, or sunscreens, since these scents are more attractive to mosquitoes.
4) Wear long, loose-fitting clothing to avoid mosquito bites.
5) Chemicals can be applied to the skin to prevent bites. DEET, has been an effective repellent that can be applied to the skin to repel mosquitoes. There are also other mosquito repellents on the market such as picaridin, oil of lemon eucalyptus, oil of eucalyptus, and soybean oil-based repellents that can be applied to the skin.

Asian tiger mosquito, Aedes albopictus (Skuse) (Diptera: Culicidae). Photo by Dr. Bart Drees, Professor and Extension Entomologist, Texas A&M Univeristy.

Swarms of Bees

Swarms of bees occur most commonly during the early spring when new queens decide to form a new nesting site. These bee swarms are less likely to be aggressive so we usually do not have to worry about stinging. However, these swarms tend to cause uproars in urban areas, if the nest settles in a backyard tree or on a porch. Also if the bees find a way to invade structures and take up residence in walls or attics, it could lead to a pretty expensive removal. If nests are not removed, the wax, honey and dead bees may produce odors that can attract other pests such as mice, ants, or cockroaches.
Some people prefer to leave their wild bee swarms alone. However if you wish to take action, the safest course is to hire a beekeeper to remove the swarm or hire a professional to eliminate it before they discover a way into structures. For more information about bees, please visit http://honeybee.tamu.edu.

An Outbreak of Sawflies!

An outbreak of pine sawflies defoliating pine trees in Lamar, Kaufman and Hunt counties have been reported, mainly on the loblolly pine. Although its identity has not been confirmed, it is likely one of the Neodiprion species of pine sawflies. Different species of sawflies cause periodic, widespread defoliation of pines throughout the southern states. The leaves (needles) of infested pines may be chewed down to the fascicles at the base of the needle bunches.

Sawflies are the only suborder of wasps, in the order Hymenoptera, that are plant feeders. They are greenish in color with dark longitudinal stripes and orange to black heads.

According to the Texas Forest Service entomologists, Joe Pase and Dr. Don Grossman, most affected trees should recover and re-leaf with no treatment. According to Pase, “The larvae feed mostly on 2nd year needles and leave the current year’s growth intact. The result is that few trees die from the defoliation. When tree mortality occurs, it is usually from attacks by pine engraver beetles (pine bark beetles) responding to stressed trees. Even then, few trees are attacked by pine beetles. Because the new growth on the trees this year has not progressed very far, the trees look especially bad, but I think most of them will come through OK – they just need a little time for the new growth to develop.”

If you feel that chemical treatment is needed, then applications of carbaryl or a pyrethroid insecticide such as bifenthrin or permethrin are suggested. Note that B.t. and spinosad are not effective against sawflies, since they are not true caterpillars.

There is usually more than one generation a year, so watch for additional feeding in late May or June. Trees that have been previously attacked may experience re-infestation by the 2nd generation. However, diseases and natural enemies usually keep later sawfly generations under natural control.

Sources: Joe Pase III, Entomologist, Texas Forest Service, jpase@tfs.tamu.edu and
Mike Merchant, Texas AgriLife Extension Entomologist, http://insectsinthecity.blogspot.com/.


Photo by: Pam Corder, Kaufman County Urban Forester.