Keeping Bugs Out With Fewer Chemicals

Most household pests come indoors for three things: food, water and shelter. Pest control professionals use an approach called integrated pest management, which focuses first on removing those attractions and blocking entry points, and uses pesticides only when needed and in targeted ways. It is effective, often cheaper than repeated spraying, and reduces chemical use around children and pets. The guide below covers the general steps, then specific pests.

The general steps

• Seal entry points. Caulk gaps around windows, pipes and cables, fit door sweeps, repair torn screens and seal cracks in foundations.
• Remove food sources. Store dry food in airtight containers, wipe counters, sweep crumbs, rinse recycling and empty kitchen bins regularly. Don't leave pet food out overnight.
• Fix moisture. Repair leaky taps and pipes, use extractor fans, and keep basements and crawl spaces dry. Many pests need water more than food.
• Reduce hiding places. Declutter, especially cardboard boxes, which attract cockroaches and silverfish, and keep firewood and mulch away from the walls of the house.
• Monitor. Sticky traps in kitchens, basements and garages show which pests you have and where they are coming from.

Ants

Ants follow scent trails to food. Wipe trails with soapy water or a vinegar solution to remove the scent, and find and seal where they are entering. Baits are usually more effective than sprays, because worker ants carry the bait back to the nest and the colony, while sprays only kill the ants you see. Place baits along trails, out of reach of children and pets, and be patient for a week or two. Carpenter ants, large black ants found in wood, can signal moisture damage and may need professional attention.

Cockroaches

Cockroaches thrive in warm, damp places with food scraps. Sanitation and fixing leaks are essential. Gel baits placed in cracks and crevices near where roaches hide, along with sticky traps for monitoring, are effective and lower risk than broad spraying. Boric acid dust applied in thin layers in wall voids and under appliances is a long-used option, but it must be kept away from children and pets. Heavy infestations, especially in apartment buildings, usually need professional and building-wide treatment.

Flies

House flies breed in garbage and decaying organic matter, so keep bins sealed and cleaned, and clean up pet waste promptly. Fruit flies breed in overripe fruit and in drains. Store ripe fruit in the fridge, clean drains and use a simple trap of apple cider vinegar with a drop of dish soap in a small container. Fly screens on windows and doors keep most flies out.

Mosquitoes

Mosquitoes lay eggs in standing water, and some species need only a small amount. Once a week, empty or scrub plant saucers, buckets, toys, birdbaths and clogged gutters. Repair window screens. For personal protection outdoors, the US Environmental Protection Agency and the CDC recommend EPA-registered repellents containing DEET, picaridin, IR3535, oil of lemon eucalyptus or 2-undecanone. Oil of lemon eucalyptus should not be used on children under three. Fans on a patio also help, since mosquitoes are weak fliers.

Pantry moths and beetles

Small moths flying in the kitchen or webbing in flour and grains signal pantry pests. Throw out infested food, vacuum shelves, especially corners and cracks, and wipe them down. Store grains, flour, nuts and dried fruit in airtight glass or hard plastic containers. Pheromone traps help monitor for moths. Freezing newly bought flour for a few days is a precaution some people use.

Spiders

Most house spiders are harmless and eat other insects. Reducing clutter, vacuuming webs and sealing gaps keeps numbers down. Outdoor lights attract insects that spiders feed on, so yellow bug lights or motion-sensor lights can help. In regions with medically significant species, such as black widows and brown recluses, take extra care in garages and storage areas and wear gloves when moving stored items.

Bed bugs

Bed bugs hide in mattress seams, bed frames and furniture near beds, and spread through luggage and secondhand furniture. Do-it-yourself treatments rarely eliminate an infestation, and foggers or "bug bombs" are ineffective against them. Contact a professional, who may use heat treatment or targeted products. When traveling, inspect hotel mattress seams, keep luggage on racks rather than the floor, and wash and dry clothes on high heat when you get home.

Seasonal checklist

Spring: check screens, seal gaps that opened over winter, and clear gutters and standing water before mosquito season. Summer: keep fruit in the fridge, empty outdoor water containers weekly and trim plants touching the house. Autumn: seal entry points before insects and rodents look for warm shelter, and store firewood away from walls. Winter: inspect basements, attics and stored boxes for signs of pests sheltering indoors.

A note on natural remedies

"Natural" does not always mean safe or effective. Many essential oils have limited evidence as pest repellents, and some, including tea tree, eucalyptus and peppermint oils, can be toxic to cats and dogs, especially when concentrated or diffused. Diatomaceous earth can help against crawling insects when kept dry, but the fine dust can irritate the lungs, so apply it carefully and use food-grade products in small amounts. Always follow label directions for any pest product, natural or not.

Rodents

Mice and rats are not insects, but they are among the most common household pests and follow the same rules. A mouse can squeeze through a gap about the width of a pencil, so seal holes around pipes and vents with steel wool and caulk or metal mesh. Store food, including pet food and birdseed, in sealed containers. Snap traps baited with peanut butter and placed along walls are effective. Avoid glue traps, which cause prolonged suffering, and keep any baits and traps away from children and pets.

When to call a professional

Bed bugs, termites, large or persistent cockroach infestations, wasp nests near doors, and any pests that are damaging the structure of your home are usually best handled by a licensed pest control professional. Ask about integrated pest management and how they minimize chemical use.