A thorough inspection is key to solving any pest problem, and this is especially true when it comes to mosquitoes. With all due respect to Sir Arthur Conan Doyle, are you a ‘sure lock’ at investigating mosquito problems and providing reliable solutions to your customers? Read on for some valuable information and tips for battling these thirsty bloodsuckers.

NECESSARY TOOLS. All mosquitoes require water to complete their life cycle so most of your inspection will involve looking for and sampling water sources. At a minimum, have a mosquito dipper (available from most biological supply companies); a plastic turkey baster for getting into small areas; plastic, resealable bags for samples; a small metal or plastic pan for examining samples; and a good flashlight. The tools will not take up much room on your truck and they are very inexpensive.

INTERVIEW THE CUSTOMER. On your initial visit, interview the customer if possible. Ask about standing water sources on the property. Are people bitten mostly during the day, in the evening or both? Are there certain areas of the yard where mosquito biting is more intense? Are they bitten inside the house? Do they have an irrigation/sprinkler system? This interview will provide valuable information to help guide your inspection and subsequent treatments. Also, look around the yard for evidence of mosquito repellents, candles, torches and other things a customer may be using to ward off mosquitoes.

top breeding spots. Mosquitoes will breed in almost anything that can hold water, from a large, neglected swimming pool to something as small as a bottle cap, so take your time and examine the premises thoroughly. A partial list of common mosquito breeding sites includes tires, outdoor sinks, buckets, pet dishes, bird baths, bottles and cans, children’s toys, flower pots and drain saucers, tarps, leaky faucets, wheelbarrows, low spots holding water, decorative fountains that aren’t maintained and kiddie pools.

Not all mosquito breeding sites are obvious. Be sure to look for water-holding plants such as bromeliads. Although these may only hold a small amount of water, they can produce enormous numbers of mosquitoes! Open and examine any in-ground drains for sprinkler and irrigation systems. Check corrugated plastic tubes used to draw water away from downspouts — frequently the ends of these tip up or curl and hold water. And don’t forget to look up during your inspection! Clogged gutters and tree holes are often the culprits. Also, while you are inspecting the premises, take note of any mosquitoes that may be attempting to bite you!

TAKE SAMPLES. Sometimes, mosquito larvae and pupae (the immature stages) can be easily seen where they are breeding, such as in a bucket or plastic bottle. Other times they may not be so obvious. For larger bodies of water, use the plastic dipper for sampling, focusing on the surface of the water. For smaller spaces such as tree holes or plants, use the turkey baster to suck the water out. Dump the water into your plastic or metal pan (a light background works best) and look for the wigglers and tumblers. Tapping the side of the pan with your baster or finger will cause the mosquitoes to move around, making them easier to see. If you choose to preserve any samples, simply dump the water and mosquitoes into one of the resealable bags.

Be advised that mosquito larvae and pupae are very sensitive to shadows and vibrations. If you cast a shadow over the breeding site or disturb it prior to sampling, the mosquitoes will dive below the surface of the water, where they can remain for a minute or so. Therefore, you may have to wait a short time before taking your sample.

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SHOW THE CUSTOMER. One of the most effective tools in your arsenal can be to show the customer the mosquitoes that you found as well as the breeding sites. Explain why the site is producing mosquitoes, what the different mosquito life stages are, and what, if anything, the customer can do about it. If you plan to treat any sites with larvicide or an insect growth regulator (IGR), explain that as well. Frequently, the customer may say something like ‘so, THAT’S what they look like. I always wondered what those were’ and they may then lead you to other breeding sites on the property that you didn’t find.

DON’T FORGET EXCLUSiON. Examine the structure(s) for mosquito entry points, especially if people are being bitten indoors. Look for torn or missing screens, broken windows, and doors that may be left open, propped open or don’t fit tightly. Mosquitoes will find their way inside buildings through the smallest of spaces! Also, some kinds of mosquitoes are highly attracted to light, so a change in lighting scheme may help.

INSPECT ON EVERY VISIT. Under ideal conditions, mosquitoes can complete their life cycle in as little as 5-7 days. Therefore, if you only visit the property every 30 days or so, you may encounter several new or previously undetected breeding sites and there may be adult mosquitoes on the loose. Hopefully, if you have properly educated your customer, some of these sites will be emptied before you arrive. Regardless, take the time on every visit to do another thorough inspection of the property.

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IN SUMMARY. Now that you have successfully found the breeding sites on your customer’s property, you can make decisions on which sources to dump or drain and which ones may need to be treated. However, do not dump or drain any water without first asking the customer, and always read and follow the label on any product you choose to use. It can also be useful to make a quick map of the property, showing where the breeding sites and any conducive conditions were for future reference.

What if you can’t find any mosquito breeding on the customer’s property, yet they are still having a mosquito problem? This is common due to the fact that some kinds of mosquitoes will fly significant distances, up to perhaps 40 miles, from their breeding sites before they feed. So, you may not be able to do anything about the breeding sites but you can offer a service to control the adult mosquitoes. And, it is always a good idea to explain situations like this to the customer.

Finally, remember that without a thorough inspection for mosquito breeding sites on each visit, your mosquito control service is likely to fail, resulting in callbacks, unhappy customers and cancellations. So, look hard and look often!

The author is vice president of technical products and services at AP&G (Catchmaster), and can be contacted at scope@catchmaster.com.

Recent attention focused on the risks associated with Zika virus and mosquito vectors, combined with demonstrated customer satisfaction for PMP mosquito service offerings, likely will increase the number of PMP barrier treatments applied in the U.S. suburban landscape (Grard et al. 2014, PCT 2015, Zanluca et al. 2015, Armstrong et al. 2016).

We, researchers at the University of Georgia, undertook three complementary studies examining PMP barrier treatments in suburban landscapes. Mosquitoes were sampled before and after treatments in field trials, including properties serviced by PMPs and research personnel. We also treated hedgerows in a nonresidential setting for further evaluation of efficacy related to residual activity. We hypothesized mosquito barrier treatments using backpack sprayers would result in a lower number of adult mosquitoes compared to untreated controls.

MATERIALS & METHODS. Our research was comprised of a variety of methodologies.

Property Owner Survey. A total of 53 property owners were given a survey inquiring about the time of day they were most likely to be outside, the amount of time they spent outside and their tolerance for mosquitoes. The survey results divided properties into categories with homeowners who reported a low tolerance for mosquitoes in their yard and those who had a higher tolerance.

Mosquito Sampling. There were three field experiments. Mosquito collection in all trials was conducted using a hand-held, commercially available vacuum device. The device was a LSWV36 Black & Decker 36V Lithium Hard Surface Sweeper Vac modified with a collection sleeve (60-cm x 60-cm; Mosquito Curtains Heavy Mosquito Curtain Netting) held in place with a rubber band (88-mm x 6-mm). The vacuum was slowly moved in and around all foliage from ground level to 6 feet in height on each property. All insects collected were confined in a collection sleeve, labeled by property and date, and the sleeve placed on ice. Upon return to the laboratory, samples were placed in a -20°C freezer for 15 minutes and emptied onto a white VERSI-DRY lab soaker paper (100-cm x 100-cm). Adult mosquitoes were identified to species and gender using dichotomous keys (Darsie and Ward 2005, Burkett-Cadena 2013).

Barrier Treatment Shadowing Study (PMP). We sampled 47 residences in this portion of the study, including 23 PMP-treated properties and 24 (2014 and 2015 respectively) control, untreated properties in the same neighborhoods. Solicitation of participants included a permission letter explaining the study. Properties were included only after obtaining a signed consent form. All residences were sampled twice a month for adult mosquitoes using the vacuum device along with visual examination of larval breeding sites and presence of larvae from July-October 2014 and May-October 2015.

We sampled mosquitoes on residential properties serviced by two pest management firms; one in Atlanta and one in Athens, Ga. Company 1 used bifenthrin and one technician treated all their residential properties sampled in 2014-15. Company 2 used a mixture of esfenvalerate, prallethrin, piperonyl butoxide and pyriproxyfen in 2014, while they used bifenthrin and a different technician to service the shadowed accounts in 2015.

Barrier treatments were applied monthly using a backpack mist blower (Stihl Model #SR420, Stihl Corp., Virginia Beach, Va.) according to protocols established by each company. Both companies applied 1.5% methoprene to obvious mosquito breeding sites including: catch basins, temporary pools and flower pot saucers. The amount of pesticide applied, property dimensions and weather data were recorded by treatment date for each company — and are available upon request from the authors.

Residential Treatments Conducted by Research Program Laboratory. We conducted a field trial complementing the PMP study. The previously described PMP-shadowing sampling protocol was employed at 9 and 15 residential structures in 2014 and 2015, respectively. Treatments in 2014 were replicated three times. They included a water-only control and two pyrethroid formulations, bifenthrin and deltamethrin, applied at the highest label rate (7.81mL/L and 11.72 mL/L per 92.9 m2, respectively). In 2015, two 25b products: one containing garlic oil and one containing an oil blend, were added to the list of treatments. Treatments were conducted using separate backpack mist blowers (Stihl Model # SR450, Stihl Corp., Virginia Beach, Va., or Solo Model #451, Solo Corp., Newport News, Va.) for each treatment. Pretreatment sampling was performed starting in July 2014 and May 2015. Treatments were applied in August. Post-treatment sampling was conducted one day after treatment and twice a month until November of both years.

Non-Residential Treatments Conducted by the Household and Structural Entomology Research Program Laboratory (hedgerow). The residual efficacy of foliar applications was further tested in experiments using 21 hedgerow sites bordering parking areas on the University of Georgia, Athens, campus. Artificial breeding sites consisting of black plastic oil pans filled three-fourths full of hay infusion were set out in April, inspected, refilled and the amount of larvae was recorded on a weekly basis. We sampled a greater number of replicates in 2015, thus, a greater amount of mosquitoes were caught that year. The five treatments included bifenthrin, deltamethrin, solutions of two 25b products — sodium lauryl sulfate, soybean oil and corn oil (oil blend), and garlic oil — plus a water-only control.

RESULTS. Researchers caught a variety of mosquitoes at a variety of sites.

Survey. The survey showed the outdoor activities of property owners were similar between the treated and untreated households (T-test P > 0.05). The majority stated they were outside in the evening (97% and 79%, treated and controls respectively) and spent more than two hours outdoors on a daily basis. Homeowners of treated properties expressed a significantly lower tolerance of mosquitoes (T-test P > 0.01) than control property owners. The majority of the treatment group (90%) stated zero mosquito bites was their tolerance limit, while 42% of the controls stated a limit of 100 bites and 46% stated greater than 20 bites. Ten percent of the treated property owners stated they will always have their yard treated, while 13% of control property owners stated they would never have their yard treated.

Barrier Treatment Shadowing Study (PMP). One hundred sixty-four mosquitoes were caught at residences during the two-year PMP shadowing study. Eighty mosquitoes were caught in 2014, with five Culex pipiens complex, one Culex restuans and 74 Aedes albopictus. All 84 mosquitoes caught in 2015 were Ae. albopictus. August provided the peak number of mosquitoes; 34 and 29, in 2014 and 2015, respectively.

The number of residences with potential mosquito breeding sites varied by year because, for example, three properties completed landscape changes in late 2014 that removed breeding sites. We caught mosquitoes at most control houses where we identified breeding sites. There were 47 control properties, if we consider each year separately, and 12 had visible breeding sites. We consistently caught mosquitoes at 13 structures in that timeframe. Therefore, 100% of properties with visible breeding sites provided adult mosquitoes, while one property without a visible breeding site provided adults. In 2014, we caught mosquitoes at eight control properties as opposed to 2015 when we caught mosquitoes at five controls. The data illustrate adult mosquitoes were usually found where larval breeding sites were present, and the amount of adults present decreased after the sites were treated.

Residential Treatments Conducted by the Household and Structural Entomology Research Program Laboratory (HSERP). We caught 162 mosquitoes at 18 properties over a two year-study period, with 113 mosquitoes in 2014 from nine properties with (98%) representing Ae. albopictus (n=111), 1 Cx. pipiens complex and 1 Cx. restuans. Despite the addition of six properties, the number of mosquitoes collected in 2015 was lower (n=45) with Ae. albopictus representing 91% and the remaining 9% were Aedes vexans (n=4).

These experiments and the PMP shadowing study showed two general trends. First, properties where we caught mosquitoes were likely to have mosquitoes on additional sampling dates, and a greater number of mosquitoes were caught in 2014 than 2015. Properties we treated with bifenthrin had fewer mosquitoes than properties with the other treatments (see Table 2). The bifenthrin and deltamethrin treatments also provided significantly fewer mosquitoes than the control, garlic oil and oil blend treatments (Nguyen 2016).

Non-Residential Treatments Conducted by the Household and Structural Entomology Research Program Laboratory (hedgerow). We caught 426 mosquitoes during the two-year study with Ae. albopictus comprising more than 93% of all mosquitoes caught in both years. We also caught three Cx. pipiens complex and two Cx. restuans in 2014, and 17 Ae. vexans and 2 Aedes j. japonicus in 2015.

The hedgerow data is indicative of the clumped distribution of Ae. albopictus populations we sampled throughout these trials. Despite providing and not treating larval breeding sites in this study, only 13 of 21 sites consistently provided adult mosquitoes. Three control sites had mosquitoes the day after treatment; the garlic oil and oil blend (25b) treatments had one day of no mosquitoes, while deltamethrin sites provided at least one week and bifenthrin two weeks.

DISCUSSION. Ae. albopictus, a potential vector of several human diseases, made up most of the mosquitoes caught in the three field trials and are the main human-biting pest species found in the Georgia Piedmont (Farajollahi and Nelder 2009, Sawabe et al. 2010, Faraji et al. 2014). We, however, also collected two other potential vectors: Cx. pipiens complex and Cx. restuans (Kilpatrick et al. 2005, Ciota and Kramer 2013). The sampling data highlight and validate concerns that often drive property owners to secure PMP mosquito control services, but this work has applicability only to backpack mist blower applied barrier treatments against Asian Tiger mosquito in a suburban setting (PCT 2015). The property owner survey clearly shows that the industry services customers who have a very low tolerance to being bitten by mosquitoes while people with a high tolerance will never contract for such service.

Barrier treatments as a PMP service offering for residential accounts have a reputation for customer satisfaction (PCT 2015). Data from our field trials indicate barrier sprays with pyrethroid insecticides impact the number of adult mosquitoes on residential properties (see Table 2 and Table 3). The PMP shadowing study showed properties that hired a monthly professional service using pyrethroid insecticide barrier treatments combined with insect growth regulator (IGR) applications to potential breeding sites were less likely to have adult mosquitoes than nearby properties without such service (see Table 3). A single adulticide application to hedgerows provided support for two to four weeks’ residual efficacy for the two pyrethroid products, but not the 25b products we tested. The hedgerow and residential properties treated by the research personnel did not provide evidence for more than one-week relief from adult mosquitoes because larval breeding sites were not treated (see Table 2).

Barrier spray treatments target adult mosquitoes. We purposely did not treat known larval breeding sites at the properties or hedgerows sprayed by the research personnel where we caught mosquitoes within a week of treatment (see Table 2 and Table 3). Those data reflect the two PMP-treated properties where we caught mosquitoes in 2014, but not in 2015 when serviced by a different technician (T-V Nguyen Personal Communication). Our data convey the importance of an Integrated Pest Management (IPM) approach to residential mosquito control, especially the need to identify the mosquito species and target potential larval mosquito breeding sites with appropriate interventions (American Mosquito Control Association 2009). Our data on potential breeding sites showed treatment and control properties had similar numbers, but we caught more adult mosquitoes at control than treatment properties. This supports recommendations that interventions involving breeding sites in addition to adulticiding are essential for effective control of Ae. albopictus that do not fly great distances (Pant 1979, Laird and Miles 1983, Bonizzoni et al. 2013).

An unexpected theme in our data was the proportion of residences where no mosquitoes were caught. The PMP-treated properties provided the highest proportion of 97% (58/60) properties with no mosquitoes over the course of the two-year study. The proportion of not-treated single-family suburban properties with no mosquitoes over the same time frame was 72% (34/47). Sixty-two percent of the properties treated by the research program did not have mosquitoes. In contrast, 29% of the hedgerows provided with breeding sites did not have mosquitoes. This point has implications for designing and evaluating residential mosquito management practices. We can state 60% of suburban residential properties in north Georgia do not have significant Ae. albopictus populations, with the caveat that our sampling technique was suitable to identify pestiferous mosquito populations (Nguyen 2016).

Our work supports previous studies showing barrier treatments with bifenthrin can significantly reduce adult Ae. albopictus populations and lends support to employing an IPM approach to backyard mosquito management (Cilek and Hallmon 2006, Doyle et al. 2009, Faraji et al. 2014). Technicians should inspect, identify and treat breeding sites on each visit followed by monthly monitoring for adult mosquitoes with a vacuum device. Adulticide barrier sprays should be performed on an as-needed basis, when sampling is positive or when the homeowner reports mosquitoes. Vacuum sampling is a consistent, real-time way of assessing the presence or absence of resting mosquitoes, and can be an integral part in validating an insecticide spray program. A best practices protocol using inspections and interventions aimed at reducing on-property breeding sites combined with a vacuum sampling regime to determine the need for foliar sprays on a presence/absence action threshold would allow PMPs to address their customers’ concerns, assuage environmental concerns about pesticide over-use and perhaps reduce costs by lowering insecticide use and time on site.

Works Cited

American Mosquito Control Association. 2009. Best Management Practices for Integrated Mosquito Managements.

Armstrong, P., M. Hennessey, M. Adams, C. Cherry, S. Chiu, A. Harrist, N. Kwit, L. Lewis, D. O. McGuire, T. Oduyebo, K. Russell, P. Talley, M. Tanner, and C. Williams. 2016. Travel-Associated Zika Virus Disease Cases Among U.S. Residents - United States, January 2015-February 2016. MMWR: Morbidity & Mortality Weekly Report 65: 286-289.

Bonizzoni, M., Gasperi, G., Chen, X., & James, A. A. (2013). The invasive mosquito species Aedes albopictus: current knowledge and future perspectives. Trends in Parasitology.

Burkett-Cadena, N. D. 2013. Mosquitoes of the southeastern United States, University of Alabama Press.

Cilek, J. E., and C. F. Hallmon. 2006. Residual effectiveness of pyrethroid-treated foliage against adult Aedes albopictus and Culex quinquefasciatus in screened field cages. Journal Of The American Mosquito Control Association 22: 725-731.

Ciota, A. T., and L. D. Kramer. 2013. Vector-Virus Interactions and Transmission Dynamics of West Nile Virus. Viruses (1999-4915) 5: 3021-3047.

Darsie, R. F., and R. A. Ward. 2005. Identification and Geographical Distribution of the mosquitoes of North America, North of Mexico, University Press of Florida.

Doyle, M. A., D. L. Kline, S. A. Allan, and P. E. Kaufman. 2009. Efficacy of residual bifenthrin applied to landscape vegetation against Aedes albopictus. Journal of the American Mosquito Control Association 25: 179-183.

Faraji, A., A. Egizi, D. M. Fonseca, I. Unlu, T. Crepeau, S. P. Healy, and R. Gaugler. 2014. Comparative Host Feeding Patterns of the Asian Tiger Mosquito, Aedes albopictus, in Urban and Suburban Northeastern USA and Implications for Disease Transmission. PLoS Neglected Tropical Diseases 8: 1-11.

Farajollahi, A., and M. P. Nelder. 2009. Changes in Aedes albopictus (Diptera: Culicidae) Populations in New Jersey and Implications for Arbovirus Transmission [electronic resource]. Journal of medical entomology 46: 1220-1224.

Grard, G., M. Caron, I. M. Mombo, D. Nkoghe, S. M. Ondo, D. Jiolle, D. Fontenille, C. Paupy, and E. M. Leroy. 2014. Zika virus in Gabon (Central Africa) - 2007: a new threat from Aedes albopictus? PLoS Neglected Tropical Diseases 8: e2681-e2681.

Kilpatrick, A. M., L. D. Kramer, S. R. Campbell, E. O. Alleyne, A. P. Dobson, and P. Daszak. 2005. West Nile Virus Risk Assessment and the Bridge Vector Paradigm. Emerging Infectious Diseases 11: 425-429.

Laird, M., and J. W. Miles. 1983. Residual Insecticides in Vector Control, pp. 49-81, Integrated mosquito control methodologies. Vol. 1. Academic Press Inc.(London) Ltd.

Pant, C. 1979. Control of vectors of Japanese encephalitis. WHOIVBCI79 733.

PCT. 2015. State of the Mosquito Market Survey, pp. 1-12, Pest Control Technology. GIE Media Inc., Cleveland; USA.

Sawabe, K., I. Nishiumi, Y. Tsuda, N. Hisai, M. Kobayashi, S. Hamao, S. Kasai, K. Hoshino, H. Isawa, T. Sasaki, Y. Higa, and S. Roychoudhury. 2010. Host-Feeding Habits of Culex pipiens and Aedes albopictus (Diptera: Culicidae) Collected at the Urban and Suburban Residential Areas of Japan [electronic resource]. Journal of medical entomology 47: 442-450.

Zanluca, C., V. C. A. d. Melo, A. L. P. Mosimann, G. I. V. d. Santos, C. N. D. d. Santos, and K. Luz. 2015. First report of autochthonous transmission of Zika virus in Brazil. Memórias do Instituto Oswaldo Cruz 110: 569-572.

Nguyen is an entomologist with the Georgia Department of Public Health’s Vector-Borne & Zoonotic Diseases team. Mayes is an undergraduate entomology research associate at the University of Georgia. Forschler is an entomology professor at the University of Georgia.

Editor’s note: In May, pest control companies from Pennsylvania (Tri-County Pest Control, Inc.) and Delaware (The Bug Guy), with products donated by BASF, volunteered their time and labor to treat the training facility for the Veterans Watchmaker Initiative, a program in which war veterans — especially disabled veterans — are taught the highly skilled art of watchmaking so they can find employment in this field. Jean Taylor, president of The Bug Guy, Dover, Del., and Jim Murphy, president of Tri-County Pest Control, Inc., Aston, Pa., shared this experience in the following article.

In our industry, every now and again we are offered an opportunity to be a part of an amazing adventure. The recent collaborative efforts of Tri-County Pest Control, Inc., The Bug Guy and BASF Pest Control Solutions was one such journey.

Few people know of the amazing horology program that is happening in the small town of Odessa, Del. A very humble gentleman, Sam Cannan, has started a world-class training program called the Veterans Watchmaker Initiative. He now oversees the school and provides watchmaking training and support to honorably discharged, combat wounded and disabled veterans. These men and women learn skills that will allow them to be financially independent and all training is done at no cost to the veteran. Unfortunately, many disabled veterans struggle to find employment, so providing a viable career opportunity for our honored veterans is one of the most important things that can be done to offset this national tragedy.

The program is going exceptionally well. The school has been receiving donations from all over the world from others in the field of horology; they recognize the incredible contribution this school will make and the various lives that will be touched and changed by the mission of the Veterans Watchmaker Initiative.

In April, it was discovered that termites were beginning to surface in various parts of the training facility. The school did not have the funds to deal with this issue, so Jim Murphy, president of Tri-County Pest Control, Inc., recognized the opportunity to assist. He reached out to Ralph and Jean Taylor of The Bug Guy, Dover, Del., as a show of unity between the Pennsylvania company (Tri-County) and the Delaware company (The Bug Guy). The two companies made a plan to move forward and offer the Veterans Watchmaker Initiative a gratis termite treatment as a way to show appreciation and support to this awesome organization. BASF Pest Control Solutions was pleased to assist by supplying the two companies with Termidor HE, a premium termiticide, to accomplish the job.

Each company chose a portion of the facility to provide the necessary treatment, ensuring that no areas were left unprotected. A full exterior treatment of the structure was performed; drilling and trenching were done where necessary. The interior hot-spots were drilled and treated, and certain areas, such as partition walls, were foamed between wall studs to relieve the necessity of drilling newly tiled and carpeted floors.

The two companies, previously unknown to each other, showed that amazing accomplishments can happen when the willingness and desire to help others in need takes precedent. It was a great day of collaboration and professional unity as the two companies teamed up together to assist this awesome group. What a pleasure, and honor, to share in dignity of purpose!

Last summer, my wife and I purchased a home in the country. For the next eight months, we worked on remodeling the new house and getting the old house ready for sale. We moved in fully in April. For my wife, house hunting was a trying experience as I look at houses differently than normal folks. I remember pulling up to a few homes and telling my wife we wouldn’t be buying the house even before we fully exited the car. “Why not?” she’d ask. I would then point out various water issues and construction issues that you could see from the curb.

As a structural entomologist, I always look for pests and, of course, I’m pretty good at locating potential pest issues in any house. In one house I saw a rat in the attic; I pointed out to my wife the little doggie door downstairs. “Hey look, a rat door!” She didn’t laugh (at least not out loud).

After a long hunt, we found the house that fulfilled most all our desires with the small downside that it contained a decent number of brown recluse spiders. Brown recluse spiders in my own home? Challenge accepted!

When remodeling, one gets well acquainted with every nook and cranny of a house. I found that I had even more pressing issues than recluses. During the course of two to three PCT articles, I will relate the issues I’ve found in my home and how I’ve addressed or remediated them. In a year or so I will provide a status report on how things worked.

START WITH THE FOUNDATION. During the initial viewing of the house, I found that the 2,500+ square foot crawlspace was fairly damp — it had no plastic vapor barrier and the vents were all blocked off. The humidity was at 95 percent and many floor joists had surface molds present. The previous owners were unaware that proper crawlspace ventilation is critical to a healthy home. Also found in the crawl was a section of old wood rot related to a corner gutter leaking issue somewhere in the past, and also the accumulation of water along the foundation due to how the downspouts were situated. Old evidence of termites was also present both in the crawl and in a couple of spots inside the house. All damage was minor, however.

The first order of business after closing on the house was to remedy the moist crawl. I purchased rolls of 6 ml plastic and Temp-Vents. The house has 16 foundation vents covering all four sides of the house potentially providing excellent cross ventilation...if the old owners hadn’t blocked all the vents with metal and wood blocks.

The vapor was spread over the crawlspace floor and an open area was left about 12 inches from the walls to help prevent the crawl from drying out too fast. The metal sheets and wood blocks covering the vents were replaced with the Temp-Vents from inside the crawl (the outside has decorative metal vent covers). At the time this work was done, the humidity was at 98 percent in the crawl — two weeks later it had dropped by 20 percent. With good cross ventilation, the humidity will fluctuate during the year, which is good for helping to deter pest activity.

To treat the mold that had appeared on the floor joists and sills, I used Bora-Care with Mold-Care from Nisus. This product is specially designed for treatment of wood that has surface molds and other fungi. It works best when conducive conditions (e.g., lack of vapor barrier and adequate ventilation in my crawl) are corrected.

ATTIC SPACES. The house has two open attics — one quite large — and this is where most of the recluse spiders are located. Sticky traps placed for several weeks last summer collected a couple dozen spiders of various sizes. Visual inspections also uncovered signs of recluses such as caste skins from molting and the telltale wispy webs in cracks.

The attic has plenty of soffit vents and adequate ventilation that will be improved eventually with installation of a ridge vent. The presence of bird carcasses, wasp and mud dauber nests, and dead lady bugs in the attic indicated that large and numerous entry points into the attic from outside existed. As suspected, the gutters on the house were installed without the gutter apron flashing that should always be installed when gutters are secured to the fascia boards around a house.

Probably the key spot that is overlooked for pest, rodent and bird entry into a home is the gap that is present just under the shingles, at the edge of the roof by the fascia. The roof decking is never extended all the way to the fascia and a gap from 1 to several inches is present. L-shaped, metal flashing should be installed from the front of the flashing, sliding up under the shingles over the roof decking. With a gutter apron, it covers from inside the gutter and back up onto the roof decking. Not only does the gutter apron exclude pests and animals, it helps prevent rainwater from wicking around and into the soffit and is critical to the functioning of gutters. Keeping the soffits dry is key to stopping wood rot and deterring moisture-loving pests such as carpenter or acrobat ants, or silverfish from setting up shop there. Once a gutter apron (or other flashing) is installed around the roof line, you still need to close off any openings where the flashing meets at corners or edges of the roof line. I used Xcluder brand exclusion material to fill in most gaps or pieces of metal flashing and silicone sealant to make the roof line as tight as possible against pest intrusion.

DRAINAGE ISSUES. One thing I noted after heavy rains was how the rainwater exiting the downspouts accumulated along the foundation. I took the time to dig the trenches and install drainage pipes hooked up to each downspout and directed into my pond. Directing the water coming off the roof away from the foundation was another link in keeping the crawlspace as dry as possible.

TERMITE PROTECTION. Every structure here in the southeast U.S. (I live in West Tennessee) should be protected from termites. Since my new home already has evidence of a previous infestation that has been treated, I decided I wanted to continue that protection. I installed BASF’s Trelona ATBS Annual Termite Bait system around the house and I’m checking the stations for activity on a prescribed basis. To date, I have yet to have activity in any station but they’ve only been in the ground a few months.

SUMMARY. Many of the previously described efforts are atypical of services provided by many pest companies, though most in the termite business install vapor barriers and foundation vents. All of the steps mentioned, however, are important to long-term pest control as they focus on correcting conducive conditions and limiting pests’ access to moisture or access.

The author is with Stoy Pest Consulting.