Mosquito Control
Updated November 6, 2026
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Safety
Keep children and pets off treated grass until it dries and follow any re-entry interval printed on the product label. Never pour pesticides or larvicide into storm drains, natural waterways, or ponds with fish, and avoid spraying flowering plants while pollinators are active. Store all products in original containers away from food and drinking water, and leave foggers, misting systems, and any application near vegetable gardens to a licensed professional.
Before the visit
Before a visit, dump or scrub anything holding water for more than a few days, including plant saucers, buckets, tarps, toys, and birdbaths. Mow tall grass, thin dense shrubs, clear clogged gutters, and bring pet bowls indoors. Keep gates unlocked, secure pets inside, cover fish ponds, and note where bites happen most so the technician can focus the inspection.
Repair vs replace
Re-treatment or corrective work makes sense when bites pick back up three to four weeks after a barrier spray, when larvae reappear in water that cannot be emptied, or after heavy rain creates new breeding spots. Torn window screens, worn door sweeps, and leaky outdoor faucets or irrigation heads should be repaired promptly, since dripping water and easy entry points undo treatment results.
When to replace
Replacement is the better route when larvicide tablets or dunks are past their expiration date, when misting-system nozzles clog or crack, when trap attractants and bulbs stop drawing mosquitoes, or when screens and door sweeps are too worn to patch. Old water-holding containers that cannot be cleaned should be swapped for ones with tight lids or drainage.
Common issues
| Symptom | Likely causes | Safe check | Stop when |
|---|---|---|---|
| Bites concentrated at dawn and dusk | Adult mosquitoes resting in shaded vegetation, under decks, and along fence lines during the day | Walk the yard at those hours in light clothing and note where biting is heaviest | Bites trigger significant swelling, hives, or breathing trouble, which calls for medical attention, or heavy biting continues after a week of dumping standing water |
| Standing water that lingers for days | Clogged gutters, low spots in the yard, plant saucers, tarps, unused pools, and blocked drainage | Empty and scrub containers weekly and refresh birdbaths, since scrubbing removes eggs attached to the sides | Water cannot be drained, such as septic leaks, retention areas, or large depressions, because these need professional larvicide rather than repeated dumping |
| Wriggling larvae in containers or rain barrels | Eggs laid in stagnant water that has sat undisturbed for roughly a week | Dip a white cup into the water and look for small wriggling larvae hanging at the surface | Larvae appear in rain barrels, ponds, or troughs used by animals, where only products labeled for those specific uses should be applied |
| Daytime biting or mosquitoes inside the home | Container-breeding species that feed during the day, plus gaps in screens, door sweeps, or vents | Inspect screens for tears, check door thresholds, and look for water-holding items close to entrances | Indoor biting continues with intact screens, which points to a breeding source right next to the structure |
| Mosquito clouds rising from shrubs or grass | Adults resting in dense, humid foliage and flushing out when disturbed | Gently brush shrubs with a stick and watch for adults taking flight, then trim overgrowth and thin crowded beds | Resting mosquitoes persist after trimming and irrigation schedules are adjusted, since a barrier treatment may be needed |
| Bite activity that surges after every rain or irrigation cycle | Floodwater species hatching from eggs in low spots, plus fresh water collecting in containers | Track bites for a few days after each rain and re-walk the property for new standing water | Surges repeat every cycle despite weekly water removal, or the source appears to be off-property such as storm drains or a neighboring lot, which calls for coordinated treatment |