Utah Pests News Spring 2013


Spring Cleaning with an IPM Eye


Every year, nuisance pests are commonly submitted to the Utah Plant Pest Diagnostic Lab. Many of these pests, including boxelder bugs, hobo spiders, paper wasps, black widows, carpet beetles, Indian meal moths, clothes moths, carpenter ants, mice (the list goes on and on), can be eliminated or minimized by exclusion, sanitation, and cultural practices. While spring cleaning your home, take steps to minimize structure-infesting pests using integrated pest management (IPM).

House Exterior/Yard

Plugging holes in outdoor equipment, furniture and play structures can help minimize the presence of paper wasps and other pests.

IPM starts with prevention. Outside the home, inspect all screens, door sweeps, weather stripping, windows, foundation cracks, and other openings where pests may enter and repair the problem or seal the opening. It is also good practice to caulk or repair cracks in driveways, patios, and where hardscape meets the foundation. Seal gaps where electrical, cable, and gas or water lines enter the home.

Maintain a 2 to 3-foot buffer between the foundation and plants to prevent nuisance pests. Tree and shrub limbs that are close to the home can form bridges for ants and other pests to invade. Prune those close limbs so that there is at least a 1 foot gap to the house walls and roof. Pull mulch away from the house foundation 3 to 6 inches and minimize mulch depth to 3 inches to deter mice and ants. Make sure that mulch around plants is not touching the bark to prevent long-term plant health issues. Areas under decorative stones, yard gnomes, and other favorite lawn ornaments can provide quality sites for hobo spiders, ants, and other pests. Consider reducing yard clutter as much as possible.

To prevent paper wasps from building nests in unwanted areas, plug holes in lawn furniture, siding, play equipment, and fencing. Look for wasp nests and destroy immediately to keep them from becoming larger throughout the summer. In lawns, sandy areas are prime habitat for many solitary bees and wasps. If sandy areas and ground-nesting insects are an issue, consider replacing the sand or dirt with grass, or cover with horticultural fabric and mulch. Be wary of spiders and stinging/biting insects in water and electrical boxes.

Changing exterior lighting from the traditional bulbs to sodium vapor bulbs (the yellow ones) will go a long way to reduce insects attracted to the home at night, reducing insects coming into the home, and minimizing the presence of spiders which feed on those insects.

Carpenter ants and termites love wood. If you have a wood pile, make sure it is as far away from the home as possible. Ants, termites, and hobo spiders can live in wood piles and then invade the home. This is especially true of wood piles kept directly against outside walls. If you have stumps or dead or dying trees on the property, monitor them for pests and take action if necessary.

Clean out your gutters. Backed-up gutters can dam water during storms and create moisture issues in roofs. This can make otherwise undesirable wood material attractive to pests like carpenter ants.

Inside the Home


Indian meal moths (top) are one of Utah’s most common food-infesting pests. Various types of carpet beetles (bottom) can be found indoors infesting food or animal-based products. Improperly stored food is a common place for carpet beetle populations to grow and spread to other food items.

Pantry pests were common in 2012, especially carpet beetles, Indian meal moth, and clothes moths. When cleaning the pantry this spring, check all stored food for the presence of moths and beetles and their immature forms. Infested food should be discarded. Newly purchased food should be stored in air-tight, pest-proof containers made of clear plastic with locking lids. This will prevent access to food for many pests now, and in the future. Remember that some pests can chew right through packaging materials. Any improperly sealed food is susceptible to invasion.

Scrub the pantry while looking in hidden nooks and crannies for moths, beetles and larvae. Pantry shelving should ideally be made of metal, with the shelving composed of metal grates. This dissuades pests from hiding in shelving and from accessing food. If replacing shelving is not feasible, consider caulking small cracks and crevices in shelving to eliminate harborage sites.

Don’t forget about dog food, bird seed, and other possible food sources. Often, people store these items in the garage where they can become easily infested. Infestations from these items can spread into the home and pantry. Be sure to properly store bird seed and pet food in air-tight, lid-locking containers.

Some pests like to destroy items made of animal products, like wool sweaters, blankets, carpets, or animal mounts. Check all wool and animal-based items for the presence of insects. As with food, animal-based clothes should be stored in air-tight containers to prevent infestation. Animal mounts should be monitored on a regular basis for pests.

Vacuum and clean around baseboards where human and pet hair, dead insects, and other debris can accumulate. Other places to carefully clean are vents, window sills, sliding-door jams, couch cushions, and bathrooms. While cleaning, remember to keep an eye open for water leaks and repair as needed. Moisture in homes encourages and sustains infestations of many pests.

In general, keep clutter to a minimum, especially in the garage where widow spiders and many other pests like to hide. If clutter can’t be eliminated, try storing smaller items in larger, air-tight containers to reduce the complexity of the clutter.

Without applying any pesticides, the above techniques can go a long way to eliminate or minimize the presence of Utah’s most common structure-infesting pests. Even better than the short-term bandage of pesticides, integrated pest management practices will provide you with long-lasting and effective pest prevention well into the future. Happy spring cleaning!

-Ryan Davis, Arthropod Diagnostician