Outside Lights Don’t Have to Attract Insects
By Chris Williams on March 24, 2011.
Q. Every spring and summer we have a problem with moths flying to our front porch lights, making a mess, and sometimes ending up inside. I don’t feel safe without outside lights on. Any advice?
A. Unfortunately, it’s not just moths that are attracted to lights. Midges, mosquitoes, certain beetles, wood cockroaches, crickets, mayflies, lacewings, and European hornets are just a few of the insects that collect around lights. Other creatures, like spiders, bats, and toads are then drawn to lights to feed on the insects collecting there.
In pest control, we use insects’ attraction to lights to our advantage. There are many types of light traps that are used to monitor or control mosquitoes, house flies, and moths. There are four things that determine whether an insect is attracted to a particular light source: its brightness, its UV (ultraviolet) output, its heat (infrared energy) output, and competition from other lights.
All is not lost! Utilizing as many of these measures as possible will reduce the number of insects flying to your outdoor (or indoor) lights.
• Replace high wattage bulbs with lower wattage (less bright) bulbs or with yellow insect bulbs.
• Use sodium vapor lamps or others with low UV output. Avoid bright white or bluish mercury vapor lamps and fluorescent lamps which have a high UV output. In general, yellowish, pinkish, or orange lights are less likely to attract insects.
• Replace bulbs that put out a high amount of heat like halogen lamps or incandescent floodlights.
• When possible, set lights so that they do not turn on until at least one hour after sunset to avoid attracting any insects that fly only at dusk.
• Use diluting curtains at windows so that bright inside lights do not attract insects to windows. Turn off lights near windows when not in use.
• Shield outside lights so that the light shines only where needed, like on a front step rather than illuminating a whole wall of the house. When possible, install lights 15 to 20 feet away from the entryway, but facing toward it, rather than placing lights directly above doorways