Mosquitos abound after Hurricane Florence

By: Shannon Newton - Extension agent
Courtesy photo Mosquito populations may decline at first as heavy rains and flooding can actually flush mosquito eggs and larvae out of many breeding sites. However, with warm early fall temperatures, mosquito populations may increase significantly in 10 to 14 days.

After a long hot summer, you would think mosquitoes would have gone into hibernation. But with the large amounts of rain and standing water from Hurricane Florence combined with the unusual hot temperatures, we are having huge populations of mosquito hatch.

Mosquito populations may decline at first as heavy rains and flooding can actually flush mosquito eggs and larvae out of many breeding sites. However, with warm early fall temperatures, mosquito populations may increase significantly in 10 to 14 days. Holes in the soil left by uprooted trees, as well as tire ruts and soil erosion caused by vehicles and heavy equipment will fill quickly with water that can stagnate over days.

If the weather stays clear, then many of these temporary water sources should dry up and reduce some mosquito problems. However, widespread flooding may create more persistent pockets of stagnant water which are likely to become mosquito breeding grounds.

Tip and toss

* Overturn or empty objects that have collected storm or rain water. Items such as bird baths, wading pools, cans and buckets, old tires, flower pots and wheelbarrows are examples of places water can stand. If you’re hauling debris to a landfill or trash collection center, now is a good time to get rid of some of these unwanted containers.

* Clear gutters and downspouts of debris so that rainwater drains properly. You can also check for previously unnoticed storm damage or wood-decay.

* Remove water that collects on sagging tarpaulins or other covers on your house or property.

* Clear silt and storm debris from drainage ditches and storm drains so that water will flow and not stagnate.

* Fill in holes left by uprooted trees, vehicles or heavy equipment.

* Larger water-filled objects, such as swimming pools that become stagnant from lack of maintenance can be treated with an insecticide containing the bacteria Bacillus thuringiensis israelensis (Bti) which does not pose a hazard to animals.

* In drier areas of the yard, spraying the shrubs where mosquitoes rest will reduce the mosquito population somewhat, but it is not likely to have a significant overall impact, particularly if your neighbors do not take any corrective action. Some mosquito species travel a 100 yards or less while others can fly one-quarter mile or more in search of blood meals. (Source: NCSU Department of Entomology)

Dunks

In pools of water you cannot empty, such as rain barrels, water gardens, swimming pools and tree cavities, treat with mosquito dunks. These doughnut shaped wafers contain a naturally occurring bacterium known as Bacillus thuringiensis israelensis that kills mosquito larvae before they are able to mature. Mosquito dunks containing this bacterium are effective for around 30 days and are not harmful to fish, birds, mammals or other wildlife.

Other species of Bacillus are used by organic gardeners to control caterpillars, Colorado potato beetles, and some plant diseases. All are readily available from local garden centers. Remember that large flooded fields are impractical to treat. Repellants and sprays will be helpful in protecting yourself from mosquitos.

Use insect repellent

Use EPA-registered insect repellents that contain at least 20% DEET (products include Cutter Backwoods and Off! Deep Woods) for protection against mosquitoes, ticks, and other bugs. Other repellents protect against mosquitoes but may not be effective against ticks or other bugs:

* Picaridin (also known as KBR 3023, Bayrepel, and icaridin)

* Oil of lemon eucalyptus (OLE) or para-menthane-diol (PMD)

* IR3535

* 2-undecanone (methyl nonyl ketone)

Find the EPA-registered insect repellent that is right for you. The effectiveness of insect repellents that are not registered with the EPA, including some natural repellents, is not known. For more information see EPA’s website.

When using insect repellent, follow the instructions on the package and reapply as directed.

* In general, higher percentages of the active ingredient provide longer-lasting protection. However, this increase in protection time maximizes at about 50% DEET.

* If you are also using sunscreen, apply it first, let it dry, and then apply repellent. Do not use products that contain both sunscreen and repellent.

* Do not spray repellent on the skin under clothing.

Cover exposed skin

As much as possible, wear long-sleeved shirts, long pants, socks, and a hat. Tuck your shirt into your pants, and tuck your pants into your socks for maximum protection. Some bugs, such as tsetse flies, can bite through thin fabric. (Source: US Centers for Disease Control and Prevention)

Mosquito control requires a community effort in order to be successful. If your community has severe mosquito populations, contact your municipal government or local Health Department to find out if any area-wide spraying has been planned. Remember to balance controlling mosquitoes with harming beneficial insects!

For more information, visit the following links …

— NC State Cooperative Extension: Pests Problems after Storms and other Disasters — https://entomology.ces.ncsu.edu/pest-problems-after-storms-and-other-disasters/

— NC State Cooperative Extension: Mosquito Control Around the Home and Community — https://www.ces.ncsu.edu/depts/ent/notes/Urban/mosquito.htm

— Centers for Disease Control and Prevention: Stop Mosquitos — http://www.cdc.gov/features/stopmosquitoes/

For information or questions about mosquitos contact Shannon Newton, Area Horticulture Extension Agent, by phone at 910-277-2422 or by e-mail at [email protected] For information about Extension visit http://scotland.ces.ncsu.edu.

Courtesy photo Mosquito populations may decline at first as heavy rains and flooding can actually flush mosquito eggs and larvae out of many breeding sites. However, with warm early fall temperatures, mosquito populations may increase significantly in 10 to 14 days.
https://www.laurinburgexchange.com/wp-content/uploads/2018/09/web1_CDC_Mosquito_050118.jpgCourtesy photo Mosquito populations may decline at first as heavy rains and flooding can actually flush mosquito eggs and larvae out of many breeding sites. However, with warm early fall temperatures, mosquito populations may increase significantly in 10 to 14 days.

Shannon Newton

Extension agent