Winter has its own pest problems

Paper wasps are common throughout Texas, frequently nesting
in windows and under house eaves. With the advent of cold
weather, many of these wasps will head indoors.

Years ago, a friend described a memorable pest control experience that still makes me chuckle. It was winter, and she had noticed a few wasps flying around her immaculate home. So naturally she called her pest control company. Her technician arrived and noticed a wasp on the fireplace. When he opened the chimney flue to investigate, to his (and her) horror a large ball of paper wasps fell from the flue into his lap. He turned to my friend, fear in his eyes, and yelled, “LADY, GRAB YOUR BABY AND GET OUT OF THE HOUSE!”

I don’t recall how long it took them both to recover their wits and clear out the wasps; but if the PMP had known a little more about paper wasp biology and behavior he could have displayed more finesse and saved his customer an unnecessary fright.

Paper wasps are one of many insects that enter homes and other buildings during the fall and winter. Like paper wasps, many insects protect themselves from cold by instinctively seeking shelter in trees, natural rock formations and (in towns) buildings. This leads to a number of insects that are seen indoors only during the winter months. It’s important to realize what’s going on and how to recognize these often-interesting invaders when they show up in your account.

Polistes wasps 

Take my friend’s wasps. Paper wasps are the most common form of wasp in most Texas towns. The come in different colors and go by different names (e.g., red wasps, hornets, umbrella wasps); but all belong to the same wasp genus, Polistes. During summer months they can be recognized by their umbrella-like, paper nests that hang under eaves of houses, in sheds, and in trees. Polistes wasps do not enclose their nests with a paper envelope like hornets or yellowjackets; but they will sting anyone who gets too close or disturbs their nest. Every fall they exchange their paper nests for locations where they will be protected from ice and winter storms. Preferred sites are high points like chimneys, multifloored office buildings and towers.

Box elder bugs may enter homes in late
summer by the hundreds. 

Unlike summer-active wasps, overwintering paper wasps show little or no aggression. Without a nest to defend, wasps simply lack the instinct to sting. A fly swatter or vacuum are all that is needed to dispatch wasps safely. If my friend’s PMP had calmly put down his lapful of wasps and asked for the vacuum cleaner, no babies need have been evacuated.

Box Elder and Red-Shouldered Bugs 

Box elder and red-shouldered bugs (Boisea trivittata and Jadera haematoloma) are true bugs that feed on seeds of certain trees. They often become pests in later summer and fall when they seek protection from cold weather. To them, buildings must resemble big hollow trees, similar to what they would use for shelter in the woods. Control these insects by sealing doors and making sure window screens are tight and in good repair. Neither insect is damaging to the trees they feed on and they are mainly nuisances when they come indoors. During the summer box elder bugs will be found on box elder and maple trees. Red-shouldered bugs are feeders on soapberry, Chinaberry, golden raintree and other trees in the soapberry family.

Nipplegall Makers 

The hackberry nipplegall maker (Pachypsylla
celtidismamma) is common in homes, especially
where there is a nearby hackberry tree. 

Hackberry nipplegall makers are common wherever hackberry trees grow throughout Texas. These tiny (2 mm-long) insects are small enough to get through most window screens and any small openings in buildings. In the summer these insects form nipple-shaped galls on the leaves of hackberry and sugarberry trees. When they emerge by the thousands from their leafy homes in late summer they are commonly found indoors and especially around windowsills. The good news is that hackberry nipple-gall insects are pretty harmless. They do not bite, do not eat clothes and are a pest only because we don’t like little bugs in our homes.

Multicolored Asian Lady Beetles 

The multicolored Asian lady beetle
(Harmonia axyridis) has become a common
fall indoor pest in Texas homes.

One of the most annoying of the fall invader insects are multicolored Asian lady beetles. These large lady beetles are natives to China and have been causing homeowners headaches since the early 1990s when they first appeared in Texas. In their native Asian home, these lady beetles move into crevices in limestone bluffs in the fall. In the U.S. they are more likely to move into light-colored homes and buildings in wooded areas where the beetles feast on aphids during the summer. Caulking and sealing along roof lines and vacuuming up the (sometimes large) aggregations of beetles where they cluster indoors or in attics is the best solution.

Cricket Hunter Wasps 

The Texas cricket hunter wasp may be
one of the least well-known household
pests in Texas. 

Maybe the least widely recognized fall invader is what I call the Texas cricket hunter wasp. These medium-sized (1/2 inch), black wasps with dark wings can be found year-round but are most common indoors during warm days in the winter and spring. They are commonly seen actively climbing up and down walls of bathrooms and other living areas. So, what are these wasps doing in homes? In nature, female cricket-hunter wasps establish nest sites in holes in the ground, such as rodent burrows, and provision those holes with fresh crickets for their offspring. In urban areas the wasps substitute weep holes and cracks in soil under building foundations for nest sites. Hundreds or possibly thousands of crickets may be stashed under homes or in walls. During periods of warm weather, the wasps’ offspring that have fed on these dead crickets can emerge indoors in large numbers. For more information on these wasps, and how to deal with infestations, check out my online factsheet.

Wintertime may be slower for the pest control business in Texas, but there are still plenty of pests out there. It’s a sign of a true pest control professional to be familiar with the less commonly encountered pests--don’t be caught off-guard when that next winter pest challenge drops in your lap.

Highlights of NCUE

Albuquerque, NM was a beautiful (and tasty)
location for this year's NCUE meeting.

One of the first professional meetings I attended as a newly minted PhD entomologist was the National Conference of Urban Entomology. Held that year in College Park, Maryland, the meeting was a revelation.  Finally, I thought to myself, a gathering of people who understand what I do for a living--like a Cheers bar for entomologists!

We've all been to parties and been asked what we do for a living. Answer that you're "an entomologist who specializes in structural insect pests", and if you're lucky you'll get a wan smile. Rarely does anyone get it. Not so at the National Conference of Urban Entomology. The NCUE is a gathering of very friendly, slightly nerdy, science-oriented people who love to talk about urban insects and pest control.  No one in this group needs bother with common names when discussing Periplaneta americana, or Coptotermes formosanus. Talks like "Gut bacteria mediate aggregation in the German cockroach" are guaranteed to draw a crowd.

This year's NCUE meeting was held in Albuquerque, NM, and it did not disappoint.  Besides a short, but packed agenda of buggy stuff, Albuquerque was a wonderful place to meet.  Not a whiff of Breaking Bad drug labs, but lots of clear skies, mountain and desert views, and great New Mexican cuisine. (Oh, and The Donald was even in town one night!)

To give you an idea about what all of us bug scientists talked about in the sessions and hallways this week, here are some of my notes to self:

• Pest exclusion was the dominant topic for one session and was revisited throughout the meeting.  Imagine if homes and offices could be designed to keep pests out, or at least make them uncomfortable.  Dr. Jody Gangloff-Kaufman from the New York State IPM Program talked about two relatively new working groups dedicated to promoting better building standards to resist pests.  They call their project SCOPE (Scientific Coalition of Pest Exclusion), and the two groups focus on residential and commercial buildings, respectively.  The group has been meeting for approximately 2 years and has about 120 members.  Goals are to assemble a database of literature that supports pest exclusion (PE) concepts, and to provide checklists for builders and architects to promote better PE. A bit of controversy arose when a session speaker suggested that perhaps the typical pest control business model would not willingly embrace pest-resistant buildings. A PMP participant objected saying that offering pest proofing was an important part of their business model and how their company remained competitive.
• Dr. Chris Geiger, with the City of San Francisco, spoke about how IPM and PE principles have influenced the LEED (Leadership in Energy and Environmental Design) program. LEED remains one of the most influential and successful certification programs ever, contributing $80.6 billion to GDP between 2011-2014 and changing the way architects design modern buildings. Dr. Geiger noted that 59% of LEED-for-existing-buildings applications take advantage of points for having an IPM program in place.
       Although LEED recognizes the importance of IPM to environmentally sound construction and maintenance of buildings, it has not provided strong leadership on pest exclusion. Consequently, in 2013 Geiger led a group to produce a guidance document for architects and builders to provide specific examples of how to make buildings more pest resistant.  These guidelines are being put to work in some major public housing renovations in San Francisco, and have been offered to builders as a standard to reference when trying to achieve IPM points in LEED projects.
       Dr. Geiger hopes to update these guidelines this year, and is actively seeking experts in pest control, engineering, entomology, and architecture to be a part of the process.  If you are interested in joining his group, go to this web form to add yourself to the list of participants.
• Dr. Tim Husen with Rollins Corporation suggested that PMPs needing fast access to a listing of low toxicity products acceptable to LEED certifiers can use a mobile phone app called PestSmart, available through the Pesticide Research Institute. I found and downloaded this free app quickly on the App Store for my iPhone.  The listing is based on criteria used by the City of San Francisco in their (now extinct) Tier III list of low toxicity pesticides.  This famed list is no longer supported or updated by the City of SF, but is still sometimes referenced by architects, especially under the now dated, V3 (2009) LEED credits.  Keep in mind that the PestSmart app provides an assessment of likely toxicity, but does not take into account risk of exposure, an important component of hazard (toxicity X exposure = hazard).  
• Famed "rodentologist," Dr. Bobby Corrigan, also spoke on rat exclusion, and provided a case history from the National Park Service's African Burial Ground Monument.  A highly sensitive, historically significant site in New York City, the property was heavily rodent infested prior to Corrigan's consultation.  Xcluder Geo Mesh was installed under sod at the site, and burrows were gassed with dry ice (2 lbs per burrow system) to successfully rid the property of these "diabolically clever" pests, as Corrigan described them. Though initially more expensive, Corrigan believes the use of CO2 and advanced mesh barriers like this could be very useful for eradicating rodents from sensitive locations.
• Not surprisingly, mosquitoes were a hot topic of discussion this year. PMPs are beginning to shift their company business models to include mosquito control. Orkin's Dr. Ron Harrison noted that mosquitoes are his company's number 1 annual service offering. Rick Bell, with Arrow Exterminating, reported that his company's mosquito revenue has gone from $39,000 in 2004 to $6.5 million in 2015, all with little reliance on automated backyard mosquito misting systems.  He noted that Arrow's mosquito control customers are among their most loyal, with a 92% annual retention rate. 
• Dr. Joe Barile of Bayer Environmental Science cautioned the industry about how mosquito control is marketed. He recommended use of the term "nuisance abatement" rather than any language that implied disease elimination or protection from mosquito borne disease.
• Dr. Grayson Brown from the University of Kentucky summarized some of the latest promising technologies for residential mosquito control. He reported that the Innovative Vector Control Consortium (IVCC), a group founded over 10 years ago to seek solutions to mosquito borne disease, is currently evaluating 9 new classes of active ingredients for vector control. If even a few of these insecticides prove safe and effective, it could revolutionize adult mosquito control. He also noted that essential oils are also receiving more study as insecticides, repellents and excitatory agents to enhance the effectiveness of other products.
• Although it appears that most pest control companies rely largely on barrier sprays as a core of their mosquito control programs, pollinator and beneficial insect concerns are an issue. Consequently, there is much interest in alternatives to backyard sprays for mosquito control. Among the promising alternatives, according to Brown, are autocidal gravid oviposition (AGO) traps.  These are artificial breeding sites for Aedes mosquitoes which trap, kill, contaminate or sterilize any female mosquito lured in to lay eggs.  In one study in Puerto Rico, 3-4 large AGO sticky traps per yard were sufficient to reduce Aedes mosquito populations 53-70% and prevented mosquito outbreaks following rain in 81% of homes. 
• Pyriproxyfen, the insect growth regulator in Archer® and Nygard® insecticides, is also being tested as an active ingredient in some autocidal traps.  Research suggests that besides killing their mosquito offspring before they emerge from treated water or cups, pyriproxyfen residues in these traps transfer via the mosquito herself to other breeding sites through a process called auto-dissemination. This is one of the coolest and most selective mosquito controls I've heard of.  If proven in the field, a PMP or homeowner, could put a few gravid traps out in the yard for minimal cost and get season long mosquito suppression with no risk to bees, butterflies or other beneficial insects.  In combination with sprays and other control methods, it might be possible to achieve a high level of control and reclaim mosquito infested backyards with minimal harm to good bugs. Currently few lethal ovitraps are commercially available; but watch for new products to enter the market soon.
• No gathering of urban entomologists would be complete without a few papers on bed bugs. Though the number of bed bug papers was down this year, those presented were oriented towards the practical.  Three papers came from Virginia Tech.  Dr. Dini Miller presented on bed bug vacuums. She found that all the battery powered vacuums she tested (several Black and Decker, and Dyson models) were surprisingly effective at removing adults, nymphs, exuviae and eggs. Besides offering a cleaner and more allergen free environment, it is notable that vacuums remove the exuvia (cast skins) of bed bugs.  This is important for control, she noted, as cast skins may be used by bed bug nymphs as a refuge from sprays.  She also recommended using disposable, knee high, nylon stockings over the mouth of your vacuum (which she colorfully called "condoms for your vacuum") to isolate your catches and reduce the risk of bringing bed bugs back to the office.
• Katlyn Amos, graduate student at VT, tested two multi-action insecticides against pyrethroid resistant bed bugs.  Both Tandem and Crossfire, a new product from MGK, performed well against these resistant bugs. 
• Molly Stedfast reported on mattress encasements for bed bugs.  One of her most important findings was that not all bed bug encasements were bite-proof. After stretching encasement fabric over the mouths of glass jars filled with bed bugs, and applying the fabric-covered mouths to the arms and legs of volunteers, many of the bed bugs were able to successfully feed. But as Stedfast noted, bite resistance is not an issue for box springs.  Nor may it be that critical for bed mattresses either.  Bed bug mouthparts are only about 1 mm long, so once covered with a mattress protector and sheet, the average sleeper should be well protected from any bed bugs trapped in a tight encasement.  Tight zippers and rip resistance are probably more important features when selecting an encasement. 
• In the category of really-interesting-science-that-may-not-have-an-immediate-application, Dr. Rachel Adams, University of California-Berkeley, talked about the microbial diversity of homes.  The ability of science now to take DNA swabs and identify 40 microbes from one's forehead has rapidly progressed from my college microbiology class where "cutting edge" meant plating out and isolating a few microbe colonies on Petri dishes. This new technology means we can now isolate hundreds or thousands of fungi and bacterial DNA from the average home. The challenge we have today is understanding what these microbes are doing.  Are they reproducing, or just there because they floated in from outdoors?  And what are their human health impacts, if any? We know that microbes can positively or negatively affect our health, allergies and possibly ability to ward off disease.  One example Dr. Adams gave was the so-called 'farm effect', where children who grow up exposed to bacteria associated with cows and manure have asthma rates as much as 4X lower than urban-raised children. Insects may play a role in delivery of some of these microbes, good or bad, into homes.
• Finally,  Dr. Coby Schal, one of the most interesting and creative urban entomology researchers in the country today, spoke about the gut bacteria in German cockroaches (Blatella germanica to us entomologists!). His research has shown that it may be bacteria that are responsible for much of cockroach aggregation behavior.  Cockroaches with their full gut bacterial complement grew up faster, reproduced faster, found mates faster, and were more efficient foragers compared to cockroaches without their gut microbes.  In addition, cockroaches were more attracted to the poop of other cockroaches with buggy guts, suggesting that these microbes might hold the key to developing a better cockroach attractant for trapping and control purposes. And you might be surprised how much cockroach feces humans are exposed to. A colony of 1,000 German cockroaches (a moderate infestation in some restaurants and apartments) produces an estimated 5 grams of feces per night, or nearly 2 Kg (4 lbs) of feces a year. These same feces contain 7.5 million units of Bla-g antigens, which can cause allergies or asthma in humans in amounts as little as 8 units.

Now you know what urban entomologists talk about when they get together. The subject matter may be boring, humorous or even distasteful to the average person; but be thankful that someone is interested in this stuff.  As for me, I'm glad there's at least one place where everyone knows my name. Cheers!

Pest Prevention by Design

Imagine a community where the newest buildings were pest resistant. It would be a place where architects and engineers worked hand in hand with pest management experts to take pests into consideration during building design and construction. Foundations of these new buildings would be reinforced with termite barriers, kitchen walls could be opened easily for inspection and treatment, access points to electric utility chases would be easily reachable, exterior doors and utility penetrations would be rodent-proof, and birds would find few easily accessible perches or nesting holes. Now imagine schools and government buildings, homes and shopping centers with features that greatly simplified pest control and reduce the need for pesticides.

That's the idea behind the new Pest Prevention by Design Guidelines published this month by San Francisco Environment, a department of the city and county of San Francisco, CA. The principal author and leader of this effort is Dr. Chris Geiger, a trained entomologist and Urban Pest Management Program Manager for the City and County of San Francisco's Department of the Environment. I love Chris' up-front and down-to-earth admission in the report:

"The world is blessed with many charming, pleasurable, glamorous and enticing subjects on which to ponder. Pest management is not one of these."

How true. But of course a world without pest management would be unlivable too.

The format of the report is clean and easy
to follow. The recommendations are based
around 18 building features, and cite technical
references for the guidelines where they exist.

The new publication was and is a team effort, involving a Technical Advisory Committee that included pest management experts, PMPs, architects, and engineers. Universities in the mix included Cornell, Penn State, Texas A&M, UC Davis and Riverside, and the NJ Institute of Technology. The National Pest Management Association was involved, as well as several pest control companies.  My point is, this is not just the wild imaginings of some California tree-huggers (apologies Chris), but a serious effort to start a dialogue between us in the pest control industry and the folks who build both green and not-so-green buildings. The project was funded by the Centers for Disease Control.

I think anyone with an interest in the subject of pest proofing, owes it to themselves to take a look at the report. The authors limited the scope of the document to commercial buildings, and it is far from a perfect or complete document, as the writers will admit. But it's a start.

Looking forward there are several hopes for this project. First, we intended it (yes, I was involved too) to serve as a starting point for better dialogue with architects and engineers--two groups that historically have not been very interested in pest control.  With the current interest in green or sustainable buildings (IPM is actually a part of today's LEED green points rating system) it appears that the time may be ripe to entice these folks to take pest control more seriously. Consider that built-in pest control should mean longer useful lives for buildings, more pleasant and livable indoor environments, cleaner air and less need for pesticides--all admirable green goals.

Second, we hope that the guidelines will be referenced by green building advocates, builders of schools, those in the apartment and hospitality industries, and government officials wanting to reduce the long term maintenance costs of public buildings.  After all, pests are  frequent contributors to building decay and decline--an expensive problem for all.

Last, we intend these guidelines to be a living document. Ultimately it is intended to reside as an editable database, where suggestions and revisions can be made over time. Once a suitable web home is found, it will be easy to update and improve. If, as you read through the document, you see things that can be added or improved, we want to know about it.

I can hear grumbling by some that "if we build pest proof buildings there won't be any work left for PMPs". That I seriously doubt. It's my personal belief that as long as there are people living in buildings, there will be plenty of pests. I think that what this effort does is raise the status and profile of pest management into more of a science and less of a fire station mentality (constantly putting out preventable fires). There will be a need for PMPs to get involved with the building planning and execution process. Yes, if this concept catches on, there might be less for PMPs to do in these newer and greener buildings; but the lost jobs will be the kinds of problems that no one wants anyway--those institutionalized, chronic pest problems that seem to never go away because of filthy conditions or rundown facilities.

As for me, I know I'd rather live in a condominium or apartment, or stay at a hotel, or eat at a restaurant that was built with IPM in mind. Wouldn't you? And that's what pest prevention by design is all about.

Wanted: Buildings that build pests out

Anyone who's worked long enough in pest control has come up with bright ideas about how to do pest control better. It's called building a better mousetrap.

My current mousetrap idea is that we need to figure out how to get some of our brightest architects, engineers and code enforcement professionals to sit down together and come up with better ways to build a truly pest-proof building. Furthermore, if we were really smart, we'd market the ideas as part of the current green building movement.

And why not? Once you have a building that is either (1) very difficult for pests to get in, or (2) extremely uncomfortable for the pests that do get in, you should find yourself needing far fewer pesticides (cleaner air) and the cost of building maintenance should go down. Both clean air and reduced building maintenance costs are important to the goals of green design.

So why don't we do this? It's not because of a lack of ideas or know-how.

To pick just one pest challenge, we know a lot about ways to termite-proof a building. A quick Google search reveals, for example, that NCSU entomologist, Mike Waldvogel has a nice online guide to termite proofing a home. Building code experts have struggled with termite-proofing issues for years. The Florida Department of Agriculture and Consumer Services’ Bureau of Entomology and Pest Control has a publication about Florida's code requirements for new construction to prevent termite damage. The National Institute of Building Sciences has an interesting website on a concept they call whole building design. This group secured government funding to develop a web portal on the concept, including information on termite proofing.

The concept should apply as well to all sorts of pests including rodents, cockroaches, a variety of crawling insects, birds, bats and other wildlife.

So why don't we do the things we know work well to save the consumer or business money, and reduce our need for pesticides? I think there are many reasons that pest proofing has not gained greater acceptance in the field of building design. For one, building a pest proof building is not as sexy or high profile as an avant-garde design, or a building with high energy efficiency or even one built using recycled materials.

Another important reason is that there is currently no good venues for pest management specialists and architects and engineers to sit down and talk with each another. Entomologists and pest management specialists traditionally have their meetings, and architects and engineers have their separate meetings. Rarely do paths cross.

Last February our office held a meeting with folks from around the country to discuss some of these issues. About 40 experts in pest management, architecture and engineering participated in a three-day seminar to share ideas on designing pest-proof public and commercial buildings. We discussed how integrated pest management concepts could be blended with green-building designs. Lots of good ideas were shared, but, unfortunately, comparatively few architects and engineers were able to participate.

We hope to try again next year at the 6th International Symposium on IPM, to be held in Portland, OR. If you know of anyone with a special interest in this area, you can tell me about it through the comment button on this post. I am especially interested in connecting with people who have expertise in building engineering, architecture and building codes. It can be a long process to build a better mousetrap, but it's one that's worth pursuing.