Thursday, July 27, 2017

Chalcid wasps in homes

After identifying an unusual insect for a homeowner today, the thank you email ended with a bang. Because I was able to quickly identify her pest, which her PMP had incorrectly insisted was a "bee", she concluded, "[I guess] it's best I change pest control companies."

Brachymeria podagrica on window screen
Could you identify this insect from this picture? Brachymeria
podagrica
 is a chalcid wasp parasitoid that attacks filth flies,
like those that feed on carrion.
Ouch... I hate to hear that.

Admittedly the insect was an obscure critter. I'm guessing that not one in 100 PMPs has ever heard of a chalcid (CHAL sid) wasp before. But chalcid wasps are common natural enemies of many insect pests. Identified by their small size and giant hind femurs, the Chalcididae family makes up one of the dozen or so "parasitoid" wasp families within the bee/wasp/ant order Hymenoptera.

Parasitoid wasps are certainly one of the most fascinating and wonderful, yet horrifying, of all creatures.  So seemingly cruel in its behavior that theologians and biologists argued over the last 200 years whether the mere existence of insects like the ichneumon wasp (a cousin of the chalcid wasp) served as proof against the Christian belief in a loving Creator-God.*

Parasitoids are parasite-like predators. Like a parasite, they grow up feeding on or in a single host. But unlike true parasites, which weaken but rarely kill, parasitoids invariably kill their hosts. Parasitoids begin their lives as an egg laid by their mother on a soft part of a host's anatomy. Upon hatching the parasitoid larva burrows into the body cavity of its host and begins feeding. The larva knows instinctively to begin with the non-essential parts, prolonging the life of its victim as long as possible. Eaten alive from the inside, ultimately the host dies. Ugh.

It does sound cruel, but parasitoids are also one of nature's most effective population control agents. Without them, crops would vanish under billions of caterpillars.  Flies would breed unchecked. Even spiders would be more abundant than they already are.  Parasitoid wasps possess some of the world's sharpest "noses" (actually antennae), able to sniff out prey even when the prey are vanishingly rare. They are also smart, with some species recently being trained to sniff out illicit drugs and even bombs on the battlefield. Gardeners and farmers, especially, reap the benefits of parasitoid services every day.

The key to identifying chalcid wasps is their tiny size (this is one 
of  the larger chalcids at 5 mm), reduced veination in the wings, 
and swollen hind femurs. This Brachymeria podagrica is further 
identified by its distinctive markings. Photo courtesy Graham
Montgomery via Bugguide.net.
Admittedly we in structural pest control don't have many chances to encounter parasitic insects in our daily work.  Most parasitoid wasps live peacefully out of sight in the natural world, ill at ease in our indoor environments. Occasionally, though, parasitoid wasps make an appearance in a home or business. For this reason, it's a good idea for PMPs to know something about these insects.

The species of chalcid wasp my homeowner encountered "swarming" in her attic this spring appeared identical to other similar wasp pictures I've received recently.  These turned out to be Brachymeria podagricaa parasitoid (primarily) of flies.  Their presence indoors suggests that the source could have been a dead animal full of fly larvae somewhere in the home--a theory backed up in this case by the homeowner's report of a foul stench several days before the little wasps appeared in the attic. Likely they were drawn to the smell of the carcass in search of their blow fly hosts.

When one, or a few, unusual insects show up overnight in a structure, they are often called "accidental invaders". Accidental invaders are chance occurrences, when an insect or spider accidentally enters through an open door or window, or unsealed crack. Such accidental entries occur on a regular basis in residential accounts, but usually with a variety of arthropods.  But when several (or dozens) of the same kind of insect appear inside a home, or when the same insects show up over many days, it usually means something is afoot. Insects always have a story to tell, and they never lie.

Chalcid wasps are not likely to enter an account over and over by accident. If you find chalcids indoors, get a sample and have them identified. Brachymeria podagrica suggests the possibility of wildlife or rodents; however other species of Brachymeria and other species of chalcids are known to parasitize beetle or moth larvae, and might be evidence of a stored product pest infestation.

And remember, if you're ever unsure of the identification of an insect, don't hesitate to bring it to your in-house entomologist (if you have one), or send to your state university or other reputable insect ID authority. And don't just call something strange a "bee" unless you know for sure that it is.

* An interesting discussion of the ichneumon wasp controversy can be found in Stephen Jay Gould's essay on Non-moral Nature in the book Hen's Teeth and Horse's Toes

Wednesday, July 26, 2017

Asian tiger mosquito a focus of last week's training


Keith Haas demonstrates use of a handheld ULV applicator
for treating adult mosquitoes hiding in dense vegetation.
For which important urban insect pest did 70% of pest control companies get more calls last year? For which pest are 88% of pest management professionals (PMPs) confident that control options are better than they were five years ago?  For what pest do nearly 2/3 of companies have callback rates of 4% or less?

According to a 2017 report by MGK® Co., the repeated answer is "mosquitoes". It appears that pest control customers increasingly want to fight pesky mosquitoes in their backyards, and are willing to pay for it. 

Ultimately, this increased interest in mosquitoes is what brought 15 interested PMPs to the "Practical Mosquito Control" course last week at IPM Experience House. And, as students learned, the driving force for this demand may just be the tiny Asian tiger mosquito (ATM), Aedes albopictus, and its slightly less common cousin the yellow fever mosquito, Aedes aegypti.

A fast and opportunistic biter, tiger mosquitoes are relatively new pests, having arrived from Japan only about 30 years ago. When people complain that, "the mosquitoes are terrible this time of year", chances are they're talking about the day-flying ATM. But ironically, despite it's irritating bite, ATM is not currently a public health threat in most areas.

"The one good thing about ATM", said Scott Sawlis, county entomologist for Dallas County Health and Human Services, "is that it reminds people that they need to wear repellent, and thereby protect themselves from the more dangerous disease-carrying species."  In the Dallas area that would be Culex quinquefasciatus, the stealthier, nighttime-flying, southern house mosquito.  Even though folks don't tend to notice the house mosquito as much, it's the one to carry West Nile virus, our most serious mosquito-borne disease. 

Sawlis and fellow instructors (myself and Dr. Sonja Swiger with Texas A&M AgriLife, and Keith Haas, with Central Life Sciences), spent the day explaining to class attendees about the need for mosquito control, and some of the differences between the target species.  At the end of the day we got to practice what we learned in class by conducting an outdoor inspection and spending some workout time on microscopes looking at these tiniest of pests at a bug eye level. 

During our inspection we discovered mosquitoes breeding (naturally) just a few feet from where class took place.  Afterwards, students got to see fresh-caught mosquito eggs and watch mosquito larvae wriggle through murky breeding media.  Haas demonstrated the ability of a ULV generator to go through and around landscape vegetation, and Sawlis demonstrated proper use of a dipper when trying to determine whether mosquitoes might be breeding in a water source.

Although ATM may be one of the best things to happen to the pest control business in the past few years, it does have a darker side. The ATM is very difficult to control from city spray trucks and even from the air.  And it remains ready to transmit the viruses for Zika and dengue fever, should these diseases arrive in our area like Zika did last summer in Miami, FL and Brownsville, TX.  

One of the most effective tools, our class learned, for fighting tiger mosquitoes is the PMP. While county and city mosquito control staff must patrol streets with sprayers that treat city-blocks at a time (a technique that works well for the house mosquito), only the PMP walks backyards, identifies and treats ground-level breeding sites, and precisely targets sprays to ATM resting sites. This puts the pest control technician in an important role to reduce the most frequent mosquito bites, and to fight Zika and other Aedes-borne illnesses, should they arise here.

If you missed last week's class, and would like to learn more about control of ATM and its biting cousins, several regional training classes will be offered over the next few months.  Stay tuned here for more information.  


Wednesday, July 12, 2017

Three new Experience House Trainings

Are you looking for pest control training using a practical approach? Do you have a new employee that you'd like to provide with some of the best training available?  Then you might be interested in the three new hands-on classes being offered this summer through the new IPM Experience House in Dallas.  Here are this summer's classes with information on how to register:
IPM Experience House provides a real world
environment where technicians learn by doing.
  • Practical Mosquito Control for PMPs (next week!) July 20, 8:30 am - 3:30 pm. This class provides an introduction to mosquitoes and mosquito biology. We’ll go through some of the basics of mosquito adult and larval identification, learn how to identify mosquito risk zones around the home and how to communicate with customers about risks from mosquito-borne disease. Different insecticide application methods and equipment will be demonstrated. Training will include both classroom, and hands-on and outdoor training at IPM Experience House. Cost for the course is only $20 thanks to partial funding by the Centers for Disease Control. If you are interested, you'll have to hurry. Click here for an agenda and information on how to register today.
  • Introduction to termite control for new technicians. August 2, 8:30 am - 3:30 pm.  This class is designed to orient new termite technicians to the art and science of termite control. Termite control expert, Dr. Bob Davis, will be demonstrating practical field skills for setting up and executing a termite job. He is joined by Dr. Mike Merchant in the classroom to provide some of the basic biology of termites you need to know if you are to be on the top of your game. This is a great opportunity to train new or old employees in the field of termite control. Half of this class will be held in the classroom, and half will be outdoors, conducting a termite estimate and treatment. Cost for the course is $40, includes snacks and water. Click here for an agenda and registration information. 
  • General Household Pest Category Training. August 23, 8:30 am - 5:00 pm. This first-time offering provides the necessary Pest category training for new apprentices and an introduction to general pest control for new technicians. Topics to be covered include: introduction to entomology and the general orders of insects; general insect pests; mosquitoes; rodents and other animal pests; introduction to IPM and pesticides; and equipment used in pest control. This is a great opportunity to train new or old employees in the field of termite control. Half of this class will be held in the classroom, and half will be in the field, conducting pest control inspections at the new IPM Experience House, looking at specimens, and getting some introductory experience with monitoring and treatments. Cost for the course is $50, includes lunch, snacks and water. Click here for agenda and registration information. 
If you've not yet visited IPM Experience House, we are a new training facility designed to provide hands-on training experiences for pest management professionals doing structural pest control in Texas. We are located at 17360 Coit Road, Dallas, TX 75252.  Classes will meet in the Building E classroom (Whitehurst Education Building), and walking to the IPM Experience House for part of the training.  For a campus map, click here.  Additional questions can be directed to Sharon Harris at 972-952-9201.

IPM Experience House is made possible through the redesign of a former dormitory on the Texas A&M AgriLife Dallas campus, the facility is financially supported by Texas A&M AgriLife Extension and the Texas pest control industry.  This summer will be a great time to check us out.

Tuesday, July 11, 2017

The things we do for You

Lab-reared cockroaches being released into a
previously pristine cabinet in the restaurant zone at
IPM Experience House.  Infestation for a good cause!
Last month I did the unthinkable. I purposefully infested a home with cockroaches.

My actions, though, were not criminal and will not harm any homeowner or renter. And the newly infested house is absolutely a good cause.

The cockroach apocalypse took place at IPM Experience House--our new, Texas A&M AgriLife-hosted, training facility for pest management professionals. IPM house is a 1000 sq foot facility with simulated kitchens, nursing home room, hotel room, pantry, restaurant, and attic.  Our vision at IPM House is to pest control trainees a with a safe place to learn their trade (think jet flight simulator for PMPs!).

But how to do this? One idea that has always intrigued me is having live cockroaches (or at least realistic signs of cockroaches) as part of the IPM House experience.

So last week my research technician and I released a hundred or so Blatella germanica in two locations at the House: a kitchen cupboard and a cabinet housing our new soft drink dispenser.  The cockroaches were provided by Doug VanGundy, my friend at Zoecon Labs, a branch of Central Life Sciences.  Zoecon maintains cultures of several key insect pests as part of their research labs in Dallas and generously agreed to provide three ice cream containers full of live cockroaches for our house.

By all appearances, the disgusting little guys we released today were more than happy to escape the confines of their sterile lab culture. Within ten minutes a few of the more adventurous had traveled a dozen feet or more from their release point.

Don't get me wrong. IPM House will not be a yucky place, full of cockroach allergens and creepy roaches. Our plan is to release the cockroaches and let them get comfortable just long enough to leave their telltale signs around the simulated residential kitchen and restaurant zones.  Once we've had enough of them, we'll pursue the infestation with state of the art control tools like dusts and baits.

I figure we've already got these little guys where we want them.  IPM House is pretty clean, and holds little food apart from which we are purposefully providing. Because of its relatively sparse furnishings, there are fewer natural harborages at IPM House compared to the average home. So I'm optimistic the cleanup operation will proceed quickly.  And if a few cockroaches manage to escape our insecticide blitzkrieg, I guess we'll just have a little more realistic classroom.

We want you and your employees to experience IPM House first hand.  Our first General Household Pest technician training is scheduled for August 23. So if you have some new employees who want their first jet simulator ride, have them sign up today. Class size is limited.

CLICK HERE TO REGISTER ONLINE