Friday, February 27, 2009

Be On The Lookout For Crane Flies

Now is the time when we begin to see nuisance crane flies enter into buildings. Sometimes these flies are called “mosquito hawks” but unlike mosquitoes, these adult flies do not feed. These flies are large in size with long legs and they are only alive long enough to mate and lay more eggs for the next generation. Even though crane flies are not medically important, they are a nuisance when they enter homes and other buildings in large numbers.
The larvae of crane flies are gray in color and cylindrical in shape. These larvae are usually found in layers of decomposing leaves or in compost piles from December to January. The larvae of the crane fly have chewing mouthparts and feed on organic matter. They are beneficial, since they are decomposers.
Usually no control is needed since the adults are only here for a couple of weeks out of the year. Just remember to keep doors and windows closed as much as possible to prevent them from entering buildings!

Photo of a crane fly (Diptera: Tipulidae). Photo by Bart Drees, Professor and Extension Entomologist, Texas A&M University.

Tuesday, February 17, 2009

Subterranean Termite Swarming Season Begins

There are two subterranean termite genera that cause most of the structural damage in Texas. One genus, Reticulitermes, may become more noticeable as the reproductives begin swarming during the day in the months of February through May. Subterranean termites live in colonies underground, in order to avoid sunshine and outside air. They are social insects and have a caste system consisting of workers, soldiers, and reproductives. Each caste member within a termite colony has distinct physical and behavioral characteristics. The workers build shelter tubes or mud tubes from tiny pieces of soil, wood, and debris that are glued together using secretions and fecal material. Termites tend to have an extensive tunneling systems underground that allows them to carry food resources back into the colony.
Termites feed on any cellulose material, such as roots, paper, and cardboard. They are important to our ecosystem, since they decompose cellulose. However, subterranean termites become economic pests when they invade human dwellings and structures. Termite damage may be detected by the presence of mud tubes, damaged wood, and the swarming of winged reproductive termites. Termite damage may also be apparent on door frames or window sills or dead termites might be visible along window sills or baseboards.

Some Preventative Practices:
1) Stumps, scrap wood, grade stakes, foam boards, cardboard boxes, and newspapers found around structures should be removed.
2) Firewood, landscape timbers, and compost piles should not be stored around foundations of structures.
3) Minimize moist areas by grading the soil and installing gutters to allow water to drain away from the building.
4) Do not allow shrubs, vines, tall grasses and other dense vegetation to grow against structures. Thick vegetation makes it hard to inspect for termite activity and these plants tend to trap moisture.
5) Use mulch sparingly and do not allow the mulch to contact wood siding or framing of the doors and windows around structures.

Some Chemical Approaches to Termite Control:
If termites are found around structures some measures can be taken, such as applying liquid termiticides and/or installing baiting systems. When soil termiticides are applied, they provide a continuous chemical barrier around the structure. Termiticides should be applied in such areas as under slabs, by drilling and injecting vertically through the slab, or treating horizontally through the foundation from the exterior. There are both repellent and non-repellant liquid termiticides that can be applied around structures. The termites attempting to tunnel into the chemically treated area will either be killed or repelled, which will prevent them from entering the structure. Termite baiting systems can also be installed around structures and in conducive conditions within the area. The stations will initially contain a piece of untreated wood until termite activity is detected. Once termite activity is observed, then the untreated wood is replaced with a plastic tube containing a termiticide within a cellulose matrix. The worker termites feed on the cellulose matrix and then exchange this material with other members of the colony. This results in death of the colony members.

A winged reproductive termite, Reticulitermes spp. (Isoptera: Rhinotermitidae). Photo by J. Hamer, Texas A&M University.

Monday, February 9, 2009

Bed Bug Registry

Bed bugs are increasingly becoming a problem within homes, apartments, hotels, motel, dormitories and shelters. The common adult bed bugs, Cimex lectularius, are about 3/16 inches in length, reddish-brown in color, wingless and flattened. Female bed bugs lay their eggs in secluded areas and can deposit 1 or more eggs per day (hundreds during a lifetime). The eggs are tiny and are usually hard to see without magnification. Bed bugs usually complete their lifecycle from egg to adult in a month.
Bed bugs prefer feeding on humans, but they will also bite other warm-blooded animals, such as dogs, cats, birds and rodents. Bed bugs are active mainly at night so they feed at night. Bed bugs tend to feed on any skin exposed while sleeping, such as the face, neck, shoulders, arms and legs. Engorgement takes about three to 10minutes. Symptoms after being bitten vary. Many people develop an itchy red welt or localized swelling within a day after the bite, while other people have little or no reaction.
The welts and itching are often attributed to fleas or mosquitoes, so infestations may go a long time unnoticed. However, the likelihood of bed bug infestations increases if the affected individual has been traveling or has acquired used beds or furnishings before symptoms started to appear. Confirmation requires finding and identifying the bugs themselves, which often requires the help of a professional.
A common concern with bed bugs is whether they transmit diseases. Although bed bugs can harbor pathogens in and on their bodies, transmission to humans is considered unlikely. Even though they are not known to carry diseases, bed bugs can severely reduce quality of life by causing discomfort, sleeplessness and embarrassment.
Bed bugs are challenging insect pests to control, since they hide in small spaces. However, experienced companies know where to look for bed bugs. Assistance is required for treatment, so excess clutter should be removed. In some cases, infested mattresses and box springs will also need to be discarded. Since bed bugs can disperse throughout a building, it also may be necessary to inspect adjoining rooms and apartments.
There is now a Bedbug Registry (http://bedbugregistry.com)to give travelers and renters a way to post bed bug sightings and find out information about encounters from past guests at apartments, hotels and motels. No one is confirming these sightings so just beware.

Friday, January 30, 2009

Prevention of Larger Animals Entering Homes This Season

As we approach into colder weather, wild animals may move closer to or into our homes. They are ultimately in search of warmth and may invade under homes or in attics. It is always easier to prevent invasion than to remove them. This makes EXCLUSION the key to the prevention of wildlife invaders. Exclusion is the best way to prevent entry. Remember that rats and mice can fit through holes as small as ¼ inch in diameter, so be sure to seal all areas where sunlight can be seen. Exclusion can be accomplished by using steel mesh in the attic to close off possible entry points. The steel mesh can be stapled or nailed around whirly birds, vents and other openings in the attic. Weep holes and cracks and crevices can be sealed using steel wool. If the outside brick is light colored, then non-rust copper steel can be used. Both steel wool and steel mesh can be found at hardware stores. Trees should also be trimmed away from structures. When tree limbs are touching houses, it becomes a perfect bridge for the animals to enter homes.
Also proper sanitation is important to prevent animals from approaching homes. All food containers should be cleaned and properly contained in closed bins, in order to avoid animals entering garbage or recycle containers. Bird seed and other food items should be stored in a sealed container. Clothes, blankets and fleece should also be stored in sealed container, in order to avoid rats and other animals nesting in the materials.
If wild animals are living in or near your home, you must first figure out what animal it is before control should be taken. Mice and rats can be trapped using sticky or snap traps. These traps should be placed perpendicular to the wall, in areas where you see droppings, gnawing, urine stains, or scratch marks.
Call the city or wildlife department if larger animals are believed to be living in homes/structures. Most departments will donate a live cage trap for a period of time and most cities will pick up the trapped animals when they are caged.

Wednesday, January 21, 2009

Using Biological Control to Control Pests

Biological control is an appealing choice to control pests, since there is no persistence of insecticides in the environment or the development of pesticide resistance. The release of natural enemies such as predators, parasites and pathogens to control pests is a type of biological control called augmentation. However, the act of purchasing and releasing natural enemies for the control of insect and mite pests can be disappointing, due to level of the control achieved. Natural enemies are living organisms, so their behavior under different environmental conditions can influence the degree of pest control achieved.
When multiple pests occur within an area, then sometimes natural enemies are needed for each pest. Commercial products available for use to control insects and mites include bacteria, fungi, viruses, nematodes, parasites and predators. Timing of the release of natural enemies is critical, since most require some time to affect the pest populations. Releases of these natural enemies at low pest densities are more effective than releases conducted to reduce high pest densities. Environmental conditions can change dramatically and outdoor releases of natural enemies can be negatively affected by high winds, rain, hot or cold weather and other insects in the ecosystem. In addition, many natural enemies attack only certain life stages, such as egg or larval stage of the pest so multiple releases may be necessary.
Companies selling natural enemies should provide consumers with directions on how to use their products and provide claims of product performance. Also, the purchaser of natural enemies must be aware of legal and biological limitations of augmentive biological control methods.
Sometimes by simply restricting the use of broad-spectrum insecticides will allow naturally occurring beneficial organisms to survive and control the pest. Remember that when insecticides are used, the residues can remain on the crop or site or insecticide drift from adjacent areas can remain toxic to natural enemies long after the insecticide was applied.

Sunday, January 11, 2009

Shore Flies Indoors


Picture of adult shore fly. Photo on: http://mrec.ifas.ufl.edu/lso/fungusgnats.htm

Shore flies are usually found in greenhouses, since they are attracted to algae growing on potting soil and under greenhouse benches. However, they can be found living on many house plants as well. Shore flies are frequently confused with fungus gnats, since they are usually found together. However shore flies have short antennae, a large head with red eyes, and smokey gray wings with 5 white spots on each wing. Also shore flies are stronger fliers than fungus gnats.
Female shore flies will lay eggs singly on the surface of algae. The eggs will hatch in about 2 to 3 days. The larvae will be found on the top layer of potting soil, feeding on the algae. Shore fly larvae are 1/8 inches in length, with a brownish-yellow, legless body. The larvae do not have a distinct head capsule, but their dark mouthparts and internal organs may be visible. The larvae mature in 3 to 6 days and then pupate. The pupae are also found close to the soil surface. The adult fly will emerge 4 to 5 days later and it will feed on the same materials as the larvae. The adult fly usually stays close to the breeding sites.
Eventhough the shore fly adults and larvae do not feed on plants, they still can present problems. Adults can be a problem, since they can transmit plant pathogens, such as Pythium and other root disease organisms. Also the shore flies’ excrement can land on foliage and leave unsightly black specks.

Some Control Options:

Some Non-chemical Control Options:

1) Avoid over watering and limit fertilizer run-off. Allow soil to dry before watering again.
2) Algae should be removed from under and on benches, walls, and floors.
3) Compost should be aerated often and relocated away from doors and windows.
4) Pasteurized container mix should be used or treat potting soil with heat or steam before using it.
5) Remove standing water and eliminate any plumbing or irrigation system leaks.

Some Chemical Control Options:

Some chemical control options include using such active ingredients as bifenthrin, permethrin to control adults and azadirachtin, kinoprene, diflubenuron, or cyromazine to control larvae.

Saturday, January 3, 2009

Fungus Gnats Fluttering Around


Picture of fungus gnat. Photo found at Texas A&M University: http://hortipm.tamu.edu/pestprofiles/other/fungnatd/fungnatd.html


Bringing plants indoors could result in another flying insect fluttering around inside, since these plants could have become infested with fungus gnats during the warmer weather. Adult fungus gnats are small, 1/8 to 1/10 inches in length, grayish black in color, have a slender body with long legs and antennae. They also are identified by the Y-shaped wing vein. Fungus gnats are usually weak fliers, so they tend to rest on foliage or growing media.
The female fungus gnats will lay tiny, oval semi-transparent eggs in moist organic debris. The fungus gnat eggs hatch into legless larvae that are white to clear in color, with shiny black heads. They eat organic mulch, compost, root hairs, and fungi. The larvae can damage roots of plants, which causes wilting, poor growth and loss of foliage. The flies then pupate in the soil within silk-like cocoons. The complete lifecycle from egg to adult occurs in around 4 weeks.

Some Suggestions for Control Measures:

Prevention
1) Inspect plants before purchasing and use sterile potting soil.
2) Allow soil to dry for several days to kill some larvae, since over watering, poor drainage and water leaks can result in a large population of fungus gnats. If the top layer of the soil becomes dry, then the larvae will likely die and the females will be less likely to lay eggs in the soil.
3) Discard heavily infested plants to avoid infesting other plants.

Biological Control
1) Some predators of fungus gnat larvae include Steinernema spp. nematodes and Hypoaspis spp. mites that can be applied to the soil.
2) Bacillus thuringiensis israelensis (Bti) can be applied to the soil to control fungus gnat larvae.


Some Chemical Control Options
Larvae can be controlled by many chemicals, such as those containing azadirachtin and imidacloprid. Adult fungus gnats can be controlled by foliar treatments, such as those containing bifenthrin, permethrin, resmethrin, and neem oils.