Mosquito Control

The breeding site is almost always in the yard

A blocked gutter, a saucer under a plant pot, a tarp with a dip in it, a corrugated extension on a downspout, a toy left upside down, the fold of an unused wheelbarrow. Each of those holds enough water for a generation, and a generation takes little more than a week in warm weather.

A treatment that does not deal with the water is a treatment that gets repeated. A technician walks the yard before spraying anything, and part of the visit is telling you which containers to empty.

What a barrier treatment does and how long it lasts

A barrier treatment goes on the surfaces where mosquitoes rest during the day — the underside of leaves, dense shrubs, the shaded side of a fence, under a deck. It is not a spray over open lawn and it is not a fog that clears the air for an evening.

It lasts weeks, not a season, and it is reduced by heavy rain. Anyone quoting a permanent result is quoting something that does not exist.

What to say when you call

• How big the yard is and how much of it is shaded or planted.
• Whether there is standing water you already know about — a pond, a rain barrel, a low spot that stays wet.
• What time of day they are worst.
• Whether there is an event coming up, because timing the visit matters more here than for most work.