Mosquito season is in full swing throughout the Commonwealth. Mosquitoes are a perennial nuisance for which there is no easy answer. As summer continues, there will be lots of information (both good and bad) about what works and what doesn't. The following measures can afford some relief.
Eliminate Breeding Sites
Mosquitoes need quiet, non-flowing water for their development and periodic summer storms provide just such conditions. Eliminating large sources of standing water may require community-wide effort. Nonetheless, homeowners can take steps to prevent mosquitoes from breeding on their property:
- Dispose of old tires, buckets, aluminum cans, plastic sheeting, or other refuse that can hold water. Empty accumulated water from trashcans, boats, wheelbarrows, pet dishes, and flowerpot bottoms, and if possible turn them over when not in use.
- Clean debris from rain gutters and unclog obstructed down spouts. Clogged or damaged rain gutters are one of the most overlooked mosquito breeding sites around homes (not to mention, associated water damage can lead to other pest problems such as termites or carpenter ants)
- Change water in birdbaths and wading pools at least weekly, and keep swimming pools clean, chlorinated, or covered when not in use. Ornamental pools can be aerated or stocked with mosquito-eating fish. Aeration and water movement helps because mosquitoes prefer quiet, non-flowing water for egg laying and development.
- Fill or drain ditches, swampy areas, and other soil depressions and remove, drain or fill tree holes and stumps with mortar to prevent water accumulation. Eliminate standing water and seepage around animal watering troughs, cisterns, and septic tanks. Be sure cistern screens are intact and access covers fit tightly.
Larval Control
Use of a mosquito larvicide can be beneficial when it is impractical to eliminate a breeding site. Larvicides are insecticides used to control immature mosquitoes before they have a chance to develop into biting adults. Most larvicides sold to homeowners contain either the ingredient methoprene or the bacterium Bacillus thuringiensis israelensis (Bti). Neither active ingredient is harmful to fish, waterfowl, pets, or humans when used according to label directions.
Homeowners can purchase the methoprene-based larvicide, PreStrike. Several products containing the mosquito- specific bacterium, Bti, are also sold to homeowners, such as Mosquito Dunks and Quick Kill Mosquito Granules. These products can typically be found at local hardware stores or online. When using any insecticidal product, always read and follow directions on the label.
Adult Control
Adult mosquitoes prefer to rest in moist, shady areas, such as dense vegetation, during the daytime. Consequently, homeowners should remove tall weeds and overgrown vegetation from their yards. To further reduce intolerable levels of biting adult mosquitoes, residual insecticides can be applied to shrubs, hedges, and other shaded areas, such as under decks and along foundations. Residual mosquito sprays are often best applied by professional pest control firms, with the training and experience to safely and effectively apply these pesticides. When applied incorrectly, these products can be dangerous to the applicator and ineffective at controlling mosquitoes.
Exclusion
Mosquitoes can be kept out of homes by securely screening windows, doors, and porches. The occasional mosquito found indoors can be eliminated with a fly swatter. Aerosol-type insecticides labeled for mosquitoes, gnats, and other flying insects seldom provide much relief.
Topically-Applied Repellents
Repellents will help prevent bites when spending time outdoors. Traditionally, the most effective mosquito repellents contained the active ingredient diethyltoluamide (DEET) ranging from 5% to 40%. Higher percentages of DEET in the ingredients provide longer protection. Low -percentage formulations (10% or less) are suitable for shorter periods outdoors (e.g., a few hours), and are recommended for use with young children.
Two additional mosquito repellent ingredients are also available, specifically Picaridin and lemon eucalyptus oil (30% Repel Lemon Eucalyptus). Unlike DEET-based repellents, Picaridin is essentially odorless and lemon eucalyptus oil has a lemon scent. For many people, these DEET-alternative have a more pleasing feel on the skin. Always read and follow directions on the container.
Other Control Possibilities
Many consumer products claim to attract, repel, capture. or kill mosquitoes. Most of these devices do not appreciably reduce mosquito abundance or incidence of bites, or else their claims are unproven.
- Electrocuting devices or "bug zappers" using ultraviolet light as an attractant are generally ineffective in reducing outdoor populations of mosquitoes and their biting activity. Studies indicate that mosquitoes make up only a tiny percentage of the insects captured in such traps. The majority are moths, beetles and other harmless night flying insects.
- Mosquito traps utilize carbon dioxide, warmth, light, and various chemicals (e.g. octenol) as attractants and claim to capture tremendous numbers of adult mosquitoes. Such devices can be quite expensive. Performance claims to the contrary, such traps seldom have been shown to reduce populations of biting mosquitoes on one's property, or the frequency of bites. In some situations, they could even attract more mosquitoes into the area they were meant to protect.
- Portable electronic devices using high frequency, ultrasonic sound routinely appear in advertisements, claiming to keep mosquitoes and other pests at bay. Some supposedly repel mosquitoes by mimicking the wing beat frequency of a hungry dragonfly. Scientific studies have repeatedly shown these devices to be of negligible benefit in deterring mosquitoes and reducing bites. Save your money, as these devices seldom, if ever, provide any appreciable measure of protection.
- Citronella oil does have mosquito-repelling properties and the scented candles can provide some protection. For maximum effect, use multiple candles placed close (within a few feet) of where people are sitting. A single candle located at the center or edge of a picnic blanket probably will not provide much benefit other than atmosphere. Mosquito-repellent plants, garlic, and other oft-advertised botanical products generally are ineffective.
- Bats and certain types of birds (e.g. purple martins) are often cited as effective natural agents for managing outdoor mosquitoes. Conservation groups and nature magazines often suggest building bat and birdhouses on one's property to promote nesting and to protect against mosquitoes. Although insectivorous bats and birds do eat mosquitoes, they make up only a very small portion of their natural diet. - Much like the mechanical "bug zappers," bats and birds capture all manner of other flying insects also. Efforts to colonize and conserve these animals should not be done with the primary intent of diminishing biting mosquitoes.
When it comes to managing mosquitoes, a good rule of thumb is: if the approach or device sounds too good to be true -- it probably is.
Categories: Kentucky, Rural Lifestyle