In the pest control business, we refer to cockroaches that live their entire lives inside homes or buildings as domestic cockroaches. The German cockroach is a prime example. Those that live both inside and outside or that move in only occasionally are called peridomestic cockroaches. The main peridomestic species are the American cockroach, oriental cockroach, smokybrown cockroach, Australian cockroach and various wood cockroaches. Peridomestic cockroaches often move indoors when the weather outside becomes too hot, wet, dry or cold, or when the population gets so large that the outside harborage can no longer contain them.

Some peridomestic species, like the Pennsylvania wood cockroach, don’t survive well inside and will die quickly. Others though, like American and oriental cockroaches, can survive and breed successfully indoors if they can find an area with enough moisture.

When peridomestic cockroaches become a problem inside, pest management professionals should check for outside sources of the infestation. Unless they can find and eliminate outside harborage sites and pest-proof openings, more cockroaches will find their way inside. They often can find these roaches hiding during the day in cracks and crevices on the building. The best time to inspect is just after sunset when the cockroaches become active. To successfully address peridomestic cockroach problems in an account, consider the following inspection tips:

Check the building exterior. Inspect cracks and crevices on outside walls. Look under siding and check weep holes in brick. Check openings around pipes, wire and cables where they enter the building. Inspect around garbage cans and Dumpster areas.

Check landscaping. Peridomestic cockroaches like moist and shady areas under trees and shrubs that have lots of leaf litter or mulch. Also, check rotting stumps or logs on the ground, wood piles and tree holes. Inspect compost or debris piles. Check planters and pots near the foundation of the building. (In indoor malls and building lobbies, check the planter beds.) Some species live in palm trees, palmettos or under the loose bark of other trees. Stone fences are another common harborage site for peridomestic cockroaches.

Check sewers (see related story on page 94). The American cockroach, in particular, often lives and breeds in sewers and can invade buildings directly from the sewer system. Check sewer vaults (with the help of the local sewer authority) and unused floor drains. Make sure that there is water in floor drains.

Check beneath the building. Crawlspaces, subbasements and storage voids can serve as harborage sites for peridomestic cockroaches. Also, it’s always a good practice to look under decks.

Check above, too. These cockroaches also can be found under roof overhangs and in roof gutters where they live and feed on collected leaves and debris. Check damaged soffits.

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Controlling Cockroaches in Sewers
American cockroaches are one of the largest pest cockroaches and they also have the longest life cycle. There is only one generation produced each year. It takes the nymphs more than a year to become adults, but each American cockroach can live for more than two years.

Unlike the German cockroach which reproduces year round, there is a certain seasonality to the American cockroach’s reproductive cycle. Females deposit their egg case — containing 13 to 18 eggs — at the same time of year, usually in April and May. Nymphs hatch from these cases in early June. This means that American cockroach populations are at their highest in late summer and fall because both older adults and new nymphs are present. In the fall, the new crop of American cockroach nymphs often migrate, looking for food and overwintering sites.

American cockroaches are the most common cockroach infesting sewers and storm drains. When the nymphs leave these sites, they often end up in buildings. American cockroaches are usually found on the lower floors of a building in warm, dark, moist areas like boiler rooms, steam tunnels, garbage rooms, storage areas, basements and greenhouses. They’re generally more common in commercial accounts than in homes.

One of the ways American cockroaches get into buildings is through floor drains. If the trap becomes dry, the roaches will travel up through the sewer pipes. Your customers should flush the drain every week or two to recharge the trap. One way to keep floor drains from drying out is to add about a tablespoon of mineral oil to the water inside the floor drain. The oil floats on top of the water and keeps it from evaporating.

American cockroaches also end up inside a building when a primary sewer line backs up, flushing roaches into businesses or homes. An unnoticed break in a sewer pipe can continuously feed cockroaches into a building. Look for little-used drains, dried-up traps or sump pumps. Ask about any drains that might have been covered by new flooring or renovations without first being plugged.
Eliminating the nymphs at the appropriate time is the best way to prevent problems in the coming year. Action should be taken before the weather turns cold because at that time the cockroaches will find hiding places, will not move around much and will not feed, and will be much more difficult to control. Bait, both outdoors and indoors, is a good choice for control of these roaches in the fall because they are competing for food and will feed on almost anything. Also, apply a perimeter insecticide treatment around the structure, especially on the sides closest to the problem sewers. Thick ground cover around the perimeter of a building provides hiding places for American cockroaches and may need to be removed or trimmed to make control easier. Use a residual insecticide in indoor infested sites. Crawlspaces also may be infested and may require treatment.

In some instances, American cockroach problems can become so bad that populations in sewers will need to be controlled, but this can be a complicated “political” issue because the sewers are generally owned by a sewer authority and not by the property owner, so only the sewer authority has the legal right (and responsibility) to control cockroaches in the sewers. Sewer authorities also will be concerned about the effect of pesticides on their treatment plants and rivers or lakes downstream. Remember, do not enter a manhole or sewer for inspection or treatment unless you have been specially trained in a “Confined Spaces” program and have the proper safety equipment and then only with a properly signed entry permit.

While the American cockroach is the primary roach in sewers, in some parts of the country other roaches occupy this space. In the Southeast, the smokybrown cockroach is often found in sewers. In the West and Southwest, the oriental cockroach is a sewer inhabitant. The Pennsylvania wood roach is also found in sewers. Therefore, proper identification is essential before embarking on a treatment program. — Larry Pinto

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CONTROL RECOMMENDATIONS. A number of Integrated Pest Management techniques are useful when developing a treatment strategy for peridomestic cockroaches. The key to successful control is to treat and seal harborage sites. Consider the following six-step program:

• When cockroaches are found on the exterior, treat the cracks and crevices where they are hiding with a residual insecticide. Use liquid insecticides or granular insecticides in infested sites around the foundation, especially around windows, doors and other entry points. Treat infested voids with a liquid residual or dust.
• Make sure the harborage cracks and crevices are then caulked or sealed. Seal openings around windows, doors, vents, pipes and electrical conduits.
• Install door sweeps, thresholds and weather seals on doors, especially garage doors.
• Have your customer reduce outside lighting and/or use yellow bulbs instead.
• Have your customers move stacks of firewood, lumber, stones, etc., away from the foundation, clean gutters and avoid heavy mulching around the foundation. Dead tree stumps should be removed. Debris piles that can’t be moved can be treated with granular bait.
• Applying a regular perimeter barrier treatment can keep peridomestic cockroaches from moving into the building.

Editor’s note: This article was adapted from Techletter, a biweekly publication from Pinto & Associates, Mechanicsville, Md. To subscribe, visit www.techletter.com, or call 301/884-3020.

So, as the days got shorter and the weather turned cooler, some of the overwintering pests such as boxelder bugs, brown marmorated stink bugs, cluster flies, multi-colored Asian lady beetles (ladybugs) and kudzu bugs (presently found as far north as northern Virginia) invaded your customer’s building as a cozy place to spend the winter. And, your customer’s solution has been to have someone suck them up with a vacuum cleaner ever since.

Now, on warmer days they’ve become a major aggravation, especially on the sunny side of the building (rooms on the south and adjoining portions of the east and west walls). The complaints are ever increasing in frequency. Although these pests have been active all winter long on sunny days that warm up the sunny side of the building, their presence is becoming more common and frequent as spring approaches. So, what can you do?
 

Reinvasion Prevention.

Concentrate your efforts on the affected rooms located on the warm side of the structure, typically the south wall and the southern portions of the adjoining east and west walls.

• Suggest to clients that they first remove the pests with a shop vacuum (not for stink bugs) and immediately empty the vacuum into a plastic bag, seal the bag and dispose of it in an outside trash can. If there are literally hundreds of pests in a room or they are stink bugs, they should call a pest management professional and have the room treated. After the pests are dead, vacuum them up without stepping on or crushing any because that could cause stains on carpeting. After the pests have been removed, the only procedure that should be done to prevent their re-entry into the inside of the structure is to seal their possible routes of entry.
• Use caulk and/or foam to seal cracks and crevices. For the smaller cracks and crevices, use caulk, but be sure to use the kind that is flexible and that can be painted, or use clear, flexible caulk if you are sealing naturally finished wood or other surfaces that will not be painted. Expandable foam can be used to seal the larger cracks and crevices that are hidden from view, such as those around electrical boxes hidden by cover plates.
   

Areas to be sealed include:

• Window and door frames. Seal around the outside of the frame where the frame meets the wall.
• If your customers have double-hung windows that have window pulleys, seal the pulley holes with tape or stuff them with fabric (tie the end piece of fabric around the cord so that you can easily retrieve and remove the fabric in the spring).
• For electrical outlets and switch boxes, first be sure that the electricity is turned off, and then remove the cover plate, close the gap between the box and the wall, and replace the cover.
• For heating duct and air-return vents, remove the grate, close the gap between the duct and the wall/floor, and replace the cover.
• For light fixtures and ceiling fans, first be sure that the electricity is turned off, and then remove the fixture to the electrical box behind its base plate, seal the gap between the box and the wall, and then replace the fixture.
• For canister lights, remove the decorative trim/plate and seal the fixture-to-ceiling junction, but do not seal the air vents on canister lights (they are required to allow heat from the bulb to safely escape).
• For skylights, seal the junction of the skylight box or its trim with the ceiling.
• For baseboards, seal the junction of the baseboard to the wall and floor.
  
   

Entryway Door Prevention.

Pests coming in through the doors? Here are some tips.

• Door-to-doorframe gaps. Be sure no air is coming in around the door (use weather stripping to close any gaps). You can either use your hand to go over the door-to-frame junction to feel for colder air coming in and/or at night, with the inside lights on and the outside lights off, go outside and look for any light escaping to the outside indicating a gap to close.
• Thresholds. Close any gaps at the junction of the bottom of the door to the frame or step. Use a tight-fitting (no gaps) threshold plate and/or flexible seal for a tight fit; door sweeps can be used but don’t seal as tightly. Again, at night, no light should escape to the outside.
  
   

What Not To Do.

Tell your customers that no attempt should be made to kill these insects in wall voids at any time! Why? The bodies of dead insects attract dermestid beetles (carpet beetles, larder beetles, etc.) because they are a favorite food of their larvae (immature stages). Dermestid larvae wander and will readily enter the work space, causing frustration and concerns.

Dermestids are very difficult and sometimes impossible to eliminate in the exterior perimeter walls because the insulation present usually prevents pesticide from reaching them.

Suggest to the client that they be patient and wait until it gets warm in the spring, then they will leave your building on their own. And no, overwintering pests do not reproduce while overwintering, they wait until they leave the building for such activities.
 

What About Next Year?

Here are some tips to help sell your pest prevention services later this year. In June, seal the sunny side(s) of the building. Tips include:

• Several of these pests orient towards contrasting colors on these walls (light-colored walls with dark trim or shadows), so concentrate efforts here.
• They also like joints where structural elements meet, such as siding to foundation wall, siding elements, fascia-board junctions with masonry grooves, etc.
• Note any unsealed utility pipe wall penetrations, unscreened ventilation openings, weep holes, etc.
  
   

Added Bonus.

Think long-term. Doing the sealing as outlined previously will reduce the entrance of colder air into your customer’s building in the winter and the loss of cooler air to the outside during the warmer months of the year. This will increase the energy efficiency of their building and save energy costs.

Eric Smith is director of technical services/staff entomologist, Dodson Bros., Lynchburg, Va. He earned his undergraduate degree from Miami (Ohio) University in botany and his master’s (Purdue) and doctorate (Ohio State) degrees in entomology. He has 30+ years experience in pest management, is past president and member of Pi Chi Omega, chair of the Copesan Technical Committee, a BCE and senior author of the NPMA Field Guide to Structural Pests.

Copesan is an alliance of pest management companies with locations throughout North America. To learn more, visit www.copesan.com.

Perimeter pest services are changing. Sir Winston Churchill once said, “To improve is to change; to be perfect is to change often.” None of us are perfect (except maybe my grandkids), but we can all get better by embracing change. With change comes innovation and often a better way of doing things. Now is a great time to take a critical look at your perimeter pest management program and make it better.
 

What's changing?

After years of focusing on the safety of indoor insecticide applications, attention has shifted to insecticides applied in the outdoor environment. Several studies have confirmed the presence of pyrethroid residues in the sediment of urban streams. Pyrethroids also have been detected in water from street runoff. These residues occur at levels toxic to a small shrimp-like organism called Hyallella azteca that is killed at concentrations as low as 2 parts per trillion. This very small concentration is the equivalent of 2 drops of water in 20 Olympic-size swimming pools. Because of their widespread use and toxicity to aquatic organisms, pyrethroid insecticides are in the crosshairs of regulators — but other chemical classes are and will be scrutinized too.

To minimize runoff and drift concerns, the U.S. EPA established the pyrethroid and pyrethrin labeling initiative. Two sections of the labels are affected — “Directions for Use” and “Environmental Hazards Statements.” Manufacturers of these insecticides were notified in 2009 that revisions in label language were needed. Outdoor applications of pyrethroid and pyrethrins to impervious surfaces were limited to spot or crack and crevice treatments. Application sites on structures also were limited and no applications were to be made during rain. A transition period allowed for the change over to the new label directions. In 2013, after feedback from industry professionals, the agency made additional revisions to the labels. To better serve customers with overwintering pest problems, treatment areas were expanded to allow for broadcast applications to sites not over impervious surfaces. (Author’s note: See Nagro [2012] and the websites listed in Table 1 below for more information on pyrethroid regulations.)

Further restrictions for perimeter insecticide applications are coming in 2014. Insecticide manufacturers of certain neonicotinoid insecticides (clothianidin, dinotefuran, imidacloprid and thiamethoxam) are required to add a bee advisory box on the product’s labels in an effort to protect bee health. The new label language will apply to products with foliar applications that may result in exposure to bees. (Author’s note: For a recent review of bee health issues see Nagro [2013] and visit www.pctonline.com/pollinators.aspx for more references.)

This article addresses four topics that can help you and clients deal with changes in perimeter services. They include:

• Practical inspections for better pest management decisions.
• Tips on when to use insecticide formulations for more targeted applications.
• Pyrethroid alternatives.
• Targeted applications based on use pattern.
   

Inspections for Better Decisions.

Time invested in inspection provides many advantages. An effective inspection helps professionals identify conditions that are conducive to pests, sensitive areas around the outside of structures and pests and their possible routes of entry (see Table 2 below). For best results, gather and record this information for each service. Soon a pattern of pest activity will be evident and you will be better prepared to take on the pests as they appear.
 

Consider these practical inspection tips in your perimeter service:

Step 1: Check in with clients in person or by phone prior to service. Inquire if they have seen pests or have concerns. Has anything changed since your last visit? Inform the client about pests that are now active in the area and ensure them that you will take extra care to manage these pests around their property.

Step 2: Walk around the structure and inspect for conducive conditions, sensitive areas and possible routes of entry. Be sure to look high and low on the structure for pest problems. Move pet food and children’s toys out of the area where insecticides may be applied. While inspecting, remove spider webs with the de-webber.

Step 3: Return to a fully secured service vehicle and gather equipment and products needed to complete the service. To increase your chances of observing pest problems, conduct your service by moving in the opposite direction around the property. Take care not to walk through treated areas.

Step 4: Document results and share information with clients. Ask for their cooperation in solving pest problems.
 
 

Targeted Applications with Insecticide Formulations.

After an effective inspection you will understand the pest problems and the areas that require treatment. Weather conditions may further influence your treatment options. For targeted applications and to maximize effectiveness, take care to select the best formulation(s) for the treatment site and pests.

Liquid Sprays. Multiple insecticide formulations are available for use as liquid sprays around the perimeter of structures. Common formulations include suspension concentrates (SCs), wettable powders (WPs), capsule suspensions or microencapsulated formulations (CSs), and water soluble granules (WSGs). When should you use liquid sprays?

• When wind is calm and chance for drift is low.
• When direct contact to pests is possible. If insect nests are found, treat the nest directly.
• For residual control on surfaces likely to be contacted by pests:
  • Extend residual by applying to protected areas.
  • Liquid sprays will not penetrate dense mulch or vegetation.

Granular Insecticides. Not to be confused with granular baits, granular insecticides are ready-to-use and contain the active ingredient on a carrier like clay, ground walnut shells, sand or ground corn cobs. They kill insects as they contact the insecticide. When should you use granules?

• To treat heavy mulch and in and around vegetation. Most granules are dense and likely to penetrate and reach targeted pests.
• When wind prevents use of liquid sprays. Granules are less likely to drift than liquid sprays.
• Avoid granule use on fully exposed areas where they may be visible and create exposure to people and pets. Take care to remove from sidewalks and driveways as runoff of insecticide is more likely from these surfaces.

Dusts. Dust deposits are readily picked up by crawling insect pests. Most dusts are long lasting, especially when placed in protected voids. When should you use dusts?

• Apply in wall voids as another line of defense against perimeter pests.
• To treat pests in hollow trees and voids in landscape timbers or block walls.
• To treat nests of flying insect pests. Best done in the evening when pests have returned to the nest.
• Avoid applying excess dust as it repels pests.
• Do not apply dusts in exposed areas.
   

Baits. Various non-repellent insecticide active ingredients (i.e., boron compounds, neonicotinoids, hydramethylnon, fipronil, abamectin and indoxacarb) are available in bait formulations. They are not subject to regulations affecting pyrethroid insecticides. Baits may be applied around building perimeters as granular baits, gels and ready-to-use bait stations. When should you use baits?

• When the source of the pest problem is difficult to find. Place baits near pest activity for best results.
• To treat sensitive areas. Baits can be placed only where needed and removed when pests are controlled.
• Do not contaminate baits with other insecticides.

Pyrethroid Alternatives. You may be looking for alternatives to pyrethroids, especially during the rainy season. Unfortunately, none of the current alternatives match the favorable characteristics of pyrethroids for perimeter pest management (see Table 3 on the right). Few products are as effective as pyrethroids against spiders and as fast acting against invading pests. But there are options.

Bait formulations can be an excellent alternative since they do not contain pyrethroids or pyrethrins. Products containing active ingredients like boron compounds, fipronil, indoxacarb and plant essential oils may be used. They tend to be more selective in their activity against pests and some have other restrictions on their use. Check with your manufacturer or distributor representatives for more information. Refer to product labels for specific use directions.
 
 

Applications by Use Pattern.

Pyrethroid/pyrethrin regulations require professionals to make more direct placement of insecticides around building perimeters. Broadcast applications (other than for overwintering pests) are replaced with crack and crevice or spot applications. The size of the band treatment around perimeters is also limited.

The good news is the effectiveness of perimeter applications appears to be maintained with these more targeted applications. Professionals are getting the job done. Studies against Argentine ants in California have shown that less insecticide and more target-specific applications can effectively control these difficult ants (Klotz et al. 2009). In similar studies, Greenberg et al. (2010) found that targeted applications against Argentine ants were effective and also reduced the amount of insecticide runoff.
 
 

Wrap Up.

In this article, suggestions were presented to help you better deal with changes in perimeter pest management. Recent regulatory actions are driving changes in the way perimeter pest management services are delivered. Further restrictions on insecticide use are likely if ongoing monitoring continues to detect insecticide runoff and drift. Bee kills with possible links to insecticide use add additional pressure leading to tighter insecticide regulation. I encourage you to take a close look at your perimeter pest management program and specifically how insecticides are applied.

The author is owner of Yosemite Environmental Services, Fresno, Calif. Contact him at gbraness@giemedia.com.

References

Greenberg, L., M.K. Rust, J.H. Klotz, D. Haver, J.K. Kabashima, S. Bondarenko and J. Gan. 2010. Impact of ant control technologies on insecticide runoff and efficacy. Pest Manag. Sci. (66): 980-87.

Klotz, J.H., M.K. Rust, H.C. Field, L. Greenberg and K. Kupfer. 2009. Low impact directed sprays and liquid baits to control Argentine ants (Hymenoptera: Formicidae). Sociobiology. 54 (1): 1-8.

Nagro, A. 2012. Pyrethroids under pressure. Pest Control Tech. 40 (4): 70-92.

Nagro, A. 2013. Pollinator primer: Why bee health matters. Pest Control Tech. 41 (10): 32, 33, 36-38, 40-42, 44, 46, 47.