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Backyard Mosquito Checklist

Mosquitoes need water to stand for at least five days to breed. A container as small as a bottle cap is enough! Reduce the number of areas where water may collect and then reduce the length of time water will sit.

Use the checklist below to start eliminating mosquito breeding sites at your home. For more tips, check out the video Don't Get Bitten: Avoid Breeding Mosquitoes in your Backyard by the Maryland Department of Agriculture. A printable version of the checklist is available here.

Mosquito Breeding Site Checklist

Potential Breeding Site

How to Correct

r  Roof gutters

Clean out leaves and debris frequently and make sure gutters are installed correctly to ensure water flows freely and does not accumulate.

r  Black corrugated pipes for downspout drainage

Grooves in plastic pipes can hold enough water to breed mosquitoes. Replace with smooth piping or treat with a larvicide.

r  Buckets, watering cans, drinking 
glasses, plastic cups, bottle caps or any trash that can hold water

Store indoors or turn over. If trash, recycle or throw away.

r  Can and containers

Throw away, store indoors, turn upside down, drill holes in the bottom, or empty after rain showers.

r  Old tires

Recycle/dispose or store where they won’t collect rainwater. For playground use, drill water drainage holes. Call 240-314-8568 for disposal information.

r  Bird baths

Change the water or flush out and scrub thoroughly at least once a week or treat with a mosquito dunk*.

r  Ornamental ponds

Stock with fish (fish eat mosquito larvae), filter/aerate the water with a recirculation pump or treat with a larvicide as needed. Do not apply larvicide to ponds that connect to a stream.

r  Potted plants with saucers

Remove or empty saucers and scrub thoroughly at least once a week.

r  Swimming pools

If unused or abandoned, treat with a mosquito dunk* or other larvicide once a month. Mosquitoes can’t breed in maintained swimming pools because of the chemicals used.

r  Tarps on woodpiles and garden equipment

Empty water that collects in folds and sagging areas. Tighten or straighten so water runs off.

r  Under decks, porches or outbuildings

Fill in depressions where water can collect. Remove any container that can collect water

r  Canoes, boats

Cover with a tight-fitting tarp or store upside down.

r  Dripping outdoor faucets and window air conditioners

If water puddles, repair faucet. Place rocks under window air conditioner to ensure water runoff.

r  Children’s toys

Store indoors or in a manner that prevents water accumulation. Note that some toys have inner compartments that can hold water.

r  Wheelbarrows

Turn over when not in use.

r  Garbage cans, recycle bins, other barrels

Keep covered or drill drainage holes in bottom. Place lids on garbage cans. Store bins and barrels to allow water runoff. 

r  Low spot in yard

Level with sand or dirt. Avoid over-watering of your yard.

r  Tree stumps and hollows

Fill tree stumps and hollow areas in trees with sand.

r  Rain barrels

Make sure rain barrels have a clean screen and tight fitting lid. Drain completely and scrub thoroughly at least once a week. Treat with mosquito dunks* or other larvicide once a month. 

*Mosquito dunks contain a bacterial larvicide that can kill other aquatic insects in addition to mosquito larvae. Therefore, they should only be used in small containers of water around residential properties, private rain gardens, rain barrels and other places that do not flow into streams, lakes or rivers.