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How to Control Breeding Sites#

Potential Breeding Site

How to Correct

Any container capable of holding water

Throw away, turn over, empty once a week or drill holes in the bottom.

Bird baths

Dump out once a week or flush out with garden hose

Pet water bowls

Rinse out once a week.

Potted plants with saucers

Empty saucers or flush out with garden hose once a week.

Buckets, watering cans, drinking glasses, styrofoam cups, bottle caps  foil, other trash that can hold water

Store inside or turn over.  If trash, throw away.

Tarps or other plastic covers, flexible sandbox covers

Drain water trapped in folds and arrange so that water runs off.

Clogged rain gutters

Clean so water runs freely.

Garbage cans, other barrels
Upturned garbage can lids

Keep can covered or drill holes in bottom.  Keep lid on can or turned so water runs off.  If collecting rain water, cover with screen.

Old tires

Dispose of at the Larimer County landfill or other recycling center.  If used for playground equipment, drill holes for water to run.  If on ground, be sure holes are not blocked by mulch.

Old playground equipment

Remove and dispose of.  If it must be stored, put under cover.  Be sure water drains off.

Children's toys, especially plastic toys, "Kiddie Coops," etc.

Store inside or turn so that places that can hold water are turned down. Some toys have compartments that hold water on both sides.

Wading pools, unused or abandoned swimming pools

Turn over kiddie pools when not in use.  Larvicide unused swimming pools with "mosquito dunks" once a month.  (Mosquitoes can't breed in maintained swimming pools because of the chemicals used.)

Wheelbarrow stored outside

Turn over when not in use.

Flat roofs

Inspect for water pools. 

Dripping outdoor faucets and window air conditioners

If puddling, repair faucet.  Place rocks under window air conditioner to ensure water runs off or fill hole with dirt.

Ornamental ponds without fish

Stock with fish, apply larvicide or filter/aerate water.  (Fish eat mosquito larvae.)

Boats, canoes

Pump out bilges.  Turn over canoes and small boats. If not possible to turn over, dump out after each rain.

Under decks, porches or outbuildings:  stored items, depressions in dirt or plastic ground linings

Fill in depressions.  Remove or turn over any stored items that hold water.

Pipes, plumbing supplies with elbows (corner joints)

Store under cover.  If they must be outside, arrange so openings point down, not up.

Drainage ditch, culvert or other low areas clogged by grass and weed clippings

Remove grass and weed clippings so water can flow and/or drain freely.

Flexible plastic pipe to take water away from downspout

Replace with smooth pipe.  The grooves can hold enough water to breed mosquitoes.

Base of patio umbrella or portable basketball stand

Fill with sand or, if filled with water, be sure to screw on plug.  Keep water out of depressions on stand also.

Outdoor grills

Keep covered.  Be sure vent is closed also.

Bromiliads (plants that hold water) holes in trees or cavities formed by multiple tree trunks

Turn plant over to dump water.  For trees or plants too large to turn over,  flush out cavities with garden hose once a week.

Outside drains

Cover with screening or larvicide with "mosquito dunks/pellets."

Sump pumps

Cover with screening


Cut down and regularly mow remaining “stumps” so they can’t hold water

Hollow fence posts without caps

Put caps on open chain link or plastic fence posts

Plastic in gardens to prevent weeds

Use landscape cloth that will allow water through instead of plastic sheets