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.

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.

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.

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.

March of the Millipedes!

Due to the cold weather, we might notice another animal crawling indoors, a millipede. The adult millipedes overwinter in protected areas, so we may see them inside structures, such as greenhouses or homes. Millipedes in Texas are typically brownish in color, but can vary from red to yellow to orange. Their bodies are rounded in shape and they have four legs per body segment. Most species are less than ½ inches in length, but the species in west Texas can be up to 4 inches in length. Another characteristic of millipedes is they curl into a spiral to protect themselves when disturbed.

In the spring, the millipedes become active and the females of some species will lay eggs in the soil, while other species will give birth to living young. The immature millipedes are smaller in size with fewer legs compared to the adults. Additional segments are produced after each molt, so the millipede grows in size. Millipedes usually develop into adulthood within 21 to 25 weeks.

Millipedes feed primarily on decaying organic matter so they are generally not regarded as a pest. However if there are large numbers of millipedes, they may attack roots and leaves of seedling plants. Millipedes, such as the garden millipede, can become a pest in the greenhouse and damage crops with their chewing mouthparts. If a structure becomes infested, then control measures are usually necessary.

In addition, millipedes can excrete an irritating fluid that can irritate eyes, blister the skin or cause allergic reactions to sensitive people so control measures may be needed.

Some Control Options:

Non- Chemical Controls:

Remove areas that provide harborage such as trash piles, rocks, boards, leaf piles, compost piles. If flower beds are mulched against structures, occasionally turn the mulch to allow it to dry out. Check around doors, windows and pipe penetrations for any points of access and then seal any accessible areas that may allow millipedes to crawl indoors.

Chemical Controls:

Perimeter sprays around the foundation of a structure may prevent millipedes from moving indoors. Some products such as those containing deltamethrin, permethrin, bifenthrin or cypermethrin as active ingredients can be used. If treatment inside structures is necessary, all cracks and crevices should be treated. Products such as those containing lambda-cyhalothrin, cypermethrin, permethrin, bifenthrin, or d-limonene can be used.

Photo of a millipede, (Diplopoda). Photo by Bart Drees, Professor and Extension Entomologist, Texas A&M University.

Inviting Thrips Indoors

As the cooler weather approaches, we will begin to move our potted plants indoors. One insect that may go undetected are western flower thrips. These insects are very tiny (almost microscopic) but can be a nuisance since their mouthparts are able to penetrate into human skin, causing a prickly sensation.

Female thrips lay eggs inside plant leaf tissue, using a serrated ovipositor to cut through the plant tissue. This allows the eggs and larvae to be well protected from insecticides and natural enemies. The immature thrips will feed on the plant tissue until it falls to the ground to pupate. Thrips undergo a prepupal and pupal stage before becoming an adult.
Thrips have rasping-sucking mouthparts that allow them to cut open epidermal cells to release the cell contents that are then ingested. This causes the cells to collapse due to absence of its contents. Their feeding also causes discoloration and deformities of leaves and petals.
As thrips feed, they inject salvia into the plant tissue which allows viruses to be transmitted, such as Tomato Spot Wilt Virus and Impatiens Necrotic Spot Virus.

Some Control Options:

Cultural Control Tactics:

1) Dispose of weeds, trash or debris to reduce the thrips population, since these areas may serve as overwintering sites for thrips.
2) Avoid planting thrips susceptible plants in areas close to wheat or rye fields. Wheat and rye are both good overwintering sites for some thrips species that can move over to feed on landscape plants.
3) Discard infested plant materials to avoid infesting other plants.

Biological Control Tactics:

Some natural enemies of thrips include the adult minute pirate bug (Orius sp.), which attacks both immature and adult thrips; Neoseiulus spp. predatory mites, which attacks the first instar thrips and the soil-dwelling predacious mite, Hypoaspsis spp., which attacks the prepupal and pupal stages of thrips in the soil. Also Beauveria bassiana, a fungus, is sold in biopesticide products and is effective at controlling thrips.

Some Chemical Control Tactics:

Some chemical control options include products containing abamectin,, chlorfenapyr, chlorpyrifos, dimethoate, fenoxycarb, methiocarb, novaluron, pyridalyl, and spinosad applied as foliar sprays or systemic products containing such chemicals as imidacloprid or acephate.

Aggregating Lady Beetles

This is a simple case of a “good” guy gone “bad!” The Multi-Colored Asian Lady Beetle is an introduced insect species from Asia that is used to control landscape insect pests in the United States. They have now established themselves in many areas of the U.S., where they reduce populations of aphids and scale insects. However, this lady beetle likes to congregate in large numbers around buildings when they overwinter. This causes them to sometimes move indoors into living areas. These beetles exude a yellowish liquid when disturbed (reflux bleeding), which can stain fabric and can cause skin irritation. They can also bite, which causes a welt to form on the skin!
Exclusion practices should be used to prevent these ladybeetles from entering the structure. All cracks and crevices, such as around windows, doors, air conditioners, and utility pipes should be sealed in late summer and fall. If beetles are spotted inside the home, then a vacuum should be used to remove them. Remember to dispose of the vacuum bag outside, so the beetles do not escape and re-invade the structure.













Multicolored Asian Ladybeetle. Photo by Mike Merchant, Professor and Extension Entomologist, Texas A&M University.