Wednesday, July 29, 2020

Tubular flying insects

With the proliferation of nighttime security cameras, homeowners are seeing all sorts of wildlife activity on the driveway and porch.  This week I had an inquiry about a mysterious "tubular flying insect" that had me puzzled at first.

The inquiry went like this:

Him: "My backyard camera catches images of these tubular flying insects every night. What are they?"

Me: "Does not look like an insect. Possibly a seed or catkin from nearby tree?"

Him: [Frowning] "Theoretically possible, but unlikely given the flight pattern. I have video, but can’t upload here. These two shots are in light rain."


Me: [Lights coming on] "If your camera has a slow shutter speed this could be a flight track of a small moth over several wing beats. There is no insect shaped like the image itself though."

Him: [Still not convinced] "I suppose that could be it. This is a night vision camera. I will continue to wonder."


Me: [Now more sure of myself] "Pretty sure these are flight tracks of moths. Note the antenna on the [right] picture. Also, see https://www.thisiscolossal.com/2012/08/moth-trails-at-night/ "

Him: [Begrudgingly, for someone who realizes he has NOT just discovered an organism new to science] That makes sense. Thank you very much for your help.

After sharing this exchange with some colleagues, one of them said, "That guy sent me the same pictures a couple of years ago.  I told him they were probably moths then."

Another colleague received a similar picture several years ago and told the lady it was a moth.  She insisted, however, it must be an angel, and would he verify it so she could post (with authority of AgriLife Extension behind her, I guess) on social media?

People are funny. Welcome to the world of urban entomology and pest control.  I hope you are now prepared to be a genius to one of your customers with puzzling security camera video.

 


Friday, July 17, 2020

Bargain sale on Mallis Handbook

This post is essentially an updated reprint of a post from 2014 about a (then) sale on the Mallis Handbook of Pest Control.  A new sale, announced today, is even better than the one six years ago.

I am frequently asked (especially by prospective ACEs studying for their certification exam) what reference books I recommend. There are many of course, but one of the essential resources for any pest control company is "Mallis".

Arnold Mallis passed away in 1984, but the book he pioneered and first published in 1945 continues to get updated and republished by the Mallis Handbook Company and GIE publishing. Many PMPs today don't realize what shaky ground, scientifically speaking, PMPs were on prior to giants like Arnold Mallis and Walter Ebeling and a few university leaders who saw the need for good, science-based information for the industry. Mallis remains one of the standard sources to go to for scientifially sound information about structural insect pests and pest management.

Don't get me wrong. At 1600 pages, this is not pleasure reading... unless you're looking for a book to help you fall asleep at night. But as a reference book, the Handbook of Pest Control is excellent. I think every pest control company should have a copy.

The reason I decided to say a few words about the Mallis Handbook is that Pest Control Technology just announced an amazing sale. If you don't have a copy of this book, for a limited time you can buy a copy for $59, less than half the regular price of $149. Why the sale? An 11th edition is on the way, but you will have to wait more than a year for that one to come out. If I didn't have this one already, I would jump on it.

A wise professor of mine once told me that the savviest professionals aren't the ones who know it all; they're the ones who know where to find the answer. And believe it or not, not all the best information can be found online. Sometimes nothing beats having a good, old-fashioned book at your fingertips.

Tuesday, July 7, 2020

Flea and ant training classes

This year's ant ID class will be more physically distant than
last year's class; but will offer the same hands-on opportunities
to become an ant identification pro.
I am happy to announce two new training opportunities this summer.  The IPM Experience House is hosting a real, in-person (physically distanced) ant identification class on July 16.  Enrollment is limited to 15 and registration information can be found at https://agriliferegister.tamu.edu/productListingDetails/3150

This is the first post COVID-19 class we've offered at the Dallas Center.  We will be following university guidelines that require us to take all reasonable precautions to keep everyone safe.  Every student will have their own microscope and supplies, class size is limited and everyone will be kept at least 6 feet apart.  We ask that you bring your own mask. Disinfectant will be provided.

Now that we've covered all the essential safety information, this is a great class.  It is our goal to offer it once a year to anyone wanting to improve their ant identification skills.  The class is a mix of lecture, ant identification using microscopes, and outdoor demonstration. Our principal instructor is Dr. Robert Puckett, urban Extension entomologist from College Station. We hope to see you there.

The second opportunity I'm especially pleased to tell you about is a new online class called Flea and Tick Biology and Control.  This class can be taken on your own time, any day of the week.  Cost is only $25 for CEU credit with both Structural and Ag CEUs.  No face masks required! To learn more and to register, click here.

This course will help you identify fleas and important tick species.  It goes into the biology of these important parasites, and provides practical advice on control strategies and personal protection. Best of all, the class is designed to move quickly and keep you engaged as you learn.

These two course represent the future of pesticide applicator training as we move into a post-COVID world. We will continue to embrace the use of more training technology while continuing to make use of face-to-face classes. Expect to see more online courses like this in the future. 

As a reminder, currently the Texas Department of Agriculture allows license holders to get credit for online CEUs every other year.  If you used online CEUs last year, the Structural Pest Control Service (TDA) is allowing your to get your CEUs online again this year due to the COVID situation; however don't assume that will be allowed again. If you get even just some of your CEUs online this year, you will likely not be able to get CEUs remotely next year.  I assume that these rules will continue to evolve as technology and the world adjusts to working remotely.

For our part, I know my extension colleagues and I are all committed to making online training less painful and more interactive.   Other currently available online classes of interest to PMPs include:



Sunday, June 21, 2020

Keep looking

Cigarette and drugstore beetles can be some of the most frustrating pests to deal with. Aside from putting out pheromone traps to try and pinpoint the origin of beetles in the house, and a good initial inspection, much of the work will have to be done by your customer.

A recent email from Devin Osborne of Osborne Pest and Turf in Austin, TX illustrates the problem. A new customer called with a persistent problem of small brown beetles he thought were emerging from an old headboard.  Rule number one: Don't assume the customer is right when it comes to diagnosing a pest. For insect identification nothing beats a good microscope or hand lens and ID guides. And keep an open mind about the likely source of an insect problem regardless of the customer thinks. 

Devin did trust his field guides and experience, and diagnosed the problem as drugstore beetle. The question remained, where are they coming from? A good PMP knows that no amount of insecticide spraying can solve a stored product pest problem.  Getting to the source is essential.

The customer took Devin's advice and went through "everything from grain to leather". The only real clue was that they only showed up in the adjoining master bedroom, master bathroom and closet.  Other rooms in the house appeared to be pest-free.  Rule number two: Don't assume it is not a stored product pest just because it's not in the kitchen.

A perfect protected feeding place for drugstore
beetles.  

Hot Booties contain linseed, one of many possible
foods for cigarette beetle.  
Eventually, after encouraging the customer to keep looking--success. An old pair of slippers called "Hot Booties" were suspicious. After googling the manufacturer, the customer learned that the booties (designed to be put in the microwave to heat for toasty tootsies) were full of linseed.  Rule number three: Exercise extreme caution when googling "hot booties".  Children should probably not be present in the room when you do.

Of course linseed is a type of grain, and any grain or seed or meal is fair food for stored product pests like drugstore beetle. In fact, any type of spice (paprika is a favorite), grains, nuts, seeds, breakfast cereal, bread, pet food, even some drugs can be food for cigarette and drugstore beetles.  These two species are some of the least discriminating stored product pest feeders.

Other situations to look for:
  • taxidermy
  • old rodent bait packets or stations
  • old kid's art project
  • accumulations of dead insects in lights
  • chili pepper decorations
  • cigars and cigarettes
  • furniture stuffing
  • potpourri 
And when the homeowner insists that there is no food source nearby, tell them to keep looking.  If you have any unusual places you have discovered stored product pests, I'd love to hear them. Just add a comment in the comment section below.



Tuesday, June 16, 2020

Tiny insects tell stories

A variety of beetles with similar feeding behaviors, sometimes collectively
called "plaster beetles". Drawing from Mallis Handbook of Pest Control.
These are tiny beetles ranging in size from 1-3 mm.
Who doesn't love a story?  Humans are suckers for narratives, so it's natural we should be interested when insects have their own stories to tell.  Especially when they are tiny insects that come from, seemingly, out of nowhere.

Among the insects I've been seeing lately are a group of beetles historically called "plaster beetles" or "mold beetles".  Though no longer a very accurate moniker (since joint compound has mostly replaced plaster in construction), plaster beetles feed on the fungi and mold spores found on building materials (including plaster and gypsum) after being exposed to rain and humidity during construction. The most common plaster and mold beetles come from the families Lathridiidae and Cryptophagidae (the Latin translation of which means "hidden feeders"). According to Smith and Whitman in the NPMA Field Guide to Structural Pests, these beetles can also become serious pests in otherwise squeaky-clean pharmaceutical, food manufacturing, canning and bottling facilities.

In Frank Meek's chapter on occasional invaders in the Mallis Handbook of Pest Control, he notes that the life cycle of plaster beetles can be completed in as little as 13 to 28 days.  That's pretty fast for an insect, and it explains how hundreds or thousands of tiny beetles can "suddenly" appear, coming from the walls and flooring of new homes. These beetles can also show up in older homes when moisture and high humidity occur.

Tiny (0.75 mm) beetle larvae swept up from a wood floor with
moisture "issues". The likely diagnosis is some kind of plaster or mold
beetle. Within weeks adult beetles will be infesting the home and
puzzling everyone as to their identity. 
I have always wanted to see (but never have seen) the immature stages of these beetles feeding in walls on building materials; and I've never heard of anyone else having seen them either.  Our deductions about what plaster and mold beetles are doing indoors are based on these beetles' biology, what they are known to feed on, and accounts of when and how the adult beetles appear. 

I recently received a sample from a PMP that comes close to providing "smoking gun" evidence for how these beetles come to infest buildings.  The sample consisted of thousands of the tiniest larvae swept up from a wooden floor (see picture).  As expected, the floor reportedly had moisture issues. Somewhere, hidden under the glued-down flooring of that home,  I imagined millions of "plaster beetles" breeding while feeding on mold spores and fungi associated with the slowly rotting wood.

Most plaster beetle problems can be solved by eliminating the source of moisture (and patience).  In new homes that were exposed to the elements during construction, properly designed and installed HVAC systems should eventually drive down humidity in the walls and floors. It may take multiple months, but eventually these beetles will disappear as molds desiccate and go dormant.

Wooden floors glued to concrete slab foundations pose a different challenge, as my wife and I learned the hard way.  We paid a contractor who assured us he had successfully installed many wood floors as glue downs on concrete slab foundations (the most common house foundation in our area). A few months after installation we noticed cupping and buckling of the new floor.  A moisture meter showed high (up to 20%) moisture in parts of the installed flooring. We had no water leaks under the house, but natural moisture exists under any concrete slab.  We got off relatively easily by pulling up all warped sections of flooring, putting down a chemical moisture barrier (usually epoxy or urethane based), reinstalling the wood and having the whole floor hand-scraped to hide further imperfections. Over ten years later we've not had any more problems, but I learned my lesson.  There are plenty of contractors out there who do not plan for moisture, and hardwood floors will fail because of it.

An unidentified cossonine weevil (2 mm) collected from a home with
moisture problems.  The presence of similar-looking beetles
should alert PMPs to likely moisture issues.  Note the elongated
face typical of weevils.
While we didn't have insects associated with our wood flooring, some do. Besides plaster beetles, another insect that can occur in wood floors is a group called the "wood weevils".  This is a name for beetles in the weevil subfamily Cossoninae.  I find little written about these weevils in the scientific or pest control literature, but have seen evidence from several homes where these beetles are associated with moist wood. In nature these beetles are found in damp and rotting wood--presumably the same resource that draws these beetles indoors. Unlike termites, these wood weevils don't seem capable of feeding on dry, sound wood; so treatment consists of solving the moisture issue and replacing the damaged wood. These beetles are most likely to be confused with powderpost beetles, so look carefully before diagnosing.

The next time you are faced with tiny beetles in a home that do not seem to fit the description of stored product pests, consider plaster beetles and wood weevils. They may be trying to tell you a story about your customer's home.



Tuesday, May 12, 2020

What PMPs need to know about the Asian giant hornet

The large yellow-orange head and dark eyes and dark thorax
distinguish the Asian giant hornet from similar large wasps.
Photo courtesy Washington State Department of Agriculture.
If ever there was an insect pest designed to generate fear and panic, it would be the Asian giant hornet, Vespula mandarinia. The largest wasp in the world, with a sting once described like a hot nail being punched through the skin, we should give this wasp credit. It is one scary dude (or more accurately dude-ess).

Adding to the hornet's fearsome reputation is it's impact on honey bees. One of the favored foods for the Asian giant hornet is the brood and workers of social wasps and bees, including honey bees. In the fall hornets start actively searching for bee and wasp nests.  Once a nest is discovered, the hornets overpower the inhabitants, bite off their heads and consume the brood and honey [in the case of honey bees].

Commercial honey bee apiaries are especially vulnerable to hornet attack because of the close spacing of hives.  An apiary can quickly turn into a scene of pillage and destruction as wasps move from hive to hive.

So that's the essence of the bad news that you can read in most media accounts of the hornet. Here are a few things every PMP should know about this hornet as you talk with your customers. 

Background

The largest wasp in the world, the Asian giant hornet is
1 to 1 ½ inches long with a ¼ inch-long stinger.  Photo
courtesy Washington State Department of Agriculture.
The Asian giant hornet was first detected in September, 2019 on Vancouver Island in British Columbia, about 200 miles northwest of Seattle, WA.  In December, three months later, a dead wasp was found in the small town of Blaine, Washington (100 miles north of Seattle) and reported to the Washington Department of Agriculture.  It was confirmed as the first detection of Vespa mandarinia in the U.S.  As of last February according to the USDA, so far a total of six sightings have been confirmed from British Columbia and Washington State (September through December).

You need to know. So far this wasp is only found in Washington State and British Columbia.  There is practically zero chance that anyone outside northwest Washington and southern BC will encounter this wasp this year.  Most of your experience with this wasp will be explaining to customers why they are not the first house in their state to get Asian giant hornets, aka "murder hornets" (more on identification tips below).

Spread

Asian giant wasps from Japan (A, B), India (C.) and Washington state
(D) show some color variability, but all have the distinctive yellow-orange
head with dark eyes. Photo credits: Yasunori Koide, Wikimedia Commons
(A); Alpsdake, Wikimedia Commons (B); Chief Red Earth,
https://indiabiodiversity.org (C); Sven-Erik Spichiger, Washington State
Department of Agriculture (D). Composite image from USDA
APHIS response guidelines 2020.
Researchers are still unsure how the Asian giant hornet made its way to North America, but suspect that mated, overwintering queens may have been transported in soil-containing plant pots shipped from Asia. A similar route of entry was responsible for introducing another Asian hornet to France a few years ago.  Recent genetic analyses suggest that the wasp was introduced on at least two occasions very recently.

You need to know. Human transport of the wasp has occurred but it is likely a rare event.  It is more difficult to transport a social insect, because it must be transported either as a mated queen or as an intact colony.  Individual hornet workers do not survive long if separated from their colony.  In my opinion, this means that, given reasonable precautions, we shouldn't expect rapid spread of this wasp throughout the states.  On the other hand, it is estimated that the wasps would be capable of surviving in plant hardiness zones 6 and above, which means that about 2/3 of the U.S. may ultimately be capable of supporting this hornet.

Activity

Like our smaller, ground-nesting yellowjacket wasps, Asian giant hornets build underground nests that survive for one growing season.  Queens leave the nest with the coming of cold weather and overwinter in protected hiding places until mid-spring when they emerge and hunt by themselves. Small colonies are formed and by early- to mid-summer worker wasps are produced and cooperative nest building proceeds. Not until fall do these wasps go on their campaigns of slaughter and occupation of bee hives.

You need to know.  Most people will face little risk of stings from Asian giant hornets.  These insects are aggressively territorial only when their nest is disturbed. Nests are usually found in wooded areas and only occupied by guard hornets from mid-summer through the fall. If their biology turns out to be similar to our native yellowjacket wasps, most nest encounters (and stings) will occur after the nest grows in size in late summer and fall (September and October). There is a more limited time frame in the fall (October and November) when honey bee hives are at risk from attack by wasps.  Fall will be the time to be most concerned about stings and beehive attacks from these wasps.

Identification

This may be the most useful information in this post, as most of a PMP's role will be reassuring the public that any big insects they see are NOT Asian giant hornets.

Since this is the world's largest wasp, the first thing is to measure its length.  Workers range from 20 to 40 mm-long (up to 1 ½ inches) and queens up to 45 mm (2 inches).  While coloration patterns can differ, the most distinctive and prominent feature is the yellow head that contrasts with dark eyes and thorax. See this useful chart published by the Washington State Department of Agriculture and this training slideset developed by USDA APHIS.

North American social wasps similar to Vespa mandarinia. (clockwise from left) A. European giant hornet (Vespa crabro); B. Bald-faced hornet (Dolichovespula maculata); C. Western cicada killer (Sphecius grandis); D. Eastern cicada killer (Sphecius speciosus); E. Pacific cicada killer (Sphecius convallis). From New Pest Response Guidelines for Vespa mandarinia, USDA APHIS, 2-2020.  

The closest relative of the Asian giant hornet is Vespa crabro, the European giant hornet. In the south and west, cicada killer wasps are the most common giant hornet look-alikes, reaching up to 1 ½ inches in length, but are generally more slender and lacking the large yellow-orange head and contrasting black eyes.

You need to know. There are lots of big insects that people will mistake for Asian giant hornets.  The chance of encountering one of these invasive hornets outside of Washington state is about zero right now. But be ready to put a name on the insects your customers will bring to you.

Hornet vs. Wasp

In this post I've used the terms hornet and wasp almost interchangeably. That is because hornets are a kind of wasp.  The term wasp refers generally to any member of the insect order Hymenoptera that is not a bee or an ant.  Most of the stinging wasps we think of as pests belong to the wasp family Vespidae.  The term hornet refers to vespid wasps in the genus Vespa.  In the U.S. we have only two species of hornet, the European giant hornet and (now) the Asian giant hornet. Despite its common name, the baldfaced hornet in the genus Dolichovespula is considered a type of yellowjacket wasp, so is not technically a hornet. 

You need to know. There are only two true hornets in the U.S., however, the smaller yellowjacket wasps and Polistes paper wasps are also social and will aggressively defend their nests like hornets and some bees.  Any of these species can be considered pests when their nests are built in areas where people travel or live.

Control

Japanese hornet-hunters wear special protective gear to excavate a nest.  These special suits are designed to be slippery so the hornet cannot hold on; and are made of tough fabric that keeps stingers from penetrating. Note the use of smoke to calm the hornets while removing brood for human consumption. Photo credit Nonaka, 2008. From USDA APHIS 2020.
A variety of approaches have been taken to control the Asian giant hornet, but none seem capable of eradicating the pest at this time.  The USDA APHIS recently published response guidelines for the Asian giant hornet which includes a summary of different control measures with pros and cons of their use. Pest management professionals who encounter this hornet should be aware that traditional bee protective suits are not adequate protection for the one-quarter inch stingers carried by this hornet. In Japan special suits are sold ($700-$900) to protect people exterminating or digging up hornet colonies for food.

You need to know. Killing individual wasps through baits or sprays will not control this species. Locating and exterminating the nest is what is being attempted in Washington state right now. Anyone who encounters a suspected Asian giant hornet should contact their state department of agriculture or a university entomologist.  Do not attempt to remove or kill a suspected Asian giant hornet nest without adequate personal protective equipment.





Monday, April 20, 2020

Kudzu bug: A new Texas pest... or not?

Kudzu bug has a unique ovoid shape. The wings
are hidden under a shield-like scutellum, making
it look more like a beetle than a true bug. Photo
by Dan Suiter, University of Georgia.  

In October 2009, millions of small, pill-like bugs startled homeowners across nine counties in northeast Georgia. The never-before-seen insects covered the sides of homes by the thousands, and concerned citizens began calling Extension offices daily. Though puzzled at first, entomologists eventually identified the insect as "kudzu bug", an exotic insect never before seen in the U.S.

The kudzu bug, Megacopta cribraria, is native to Asia, where it is widely distributed. As its name implies, its preferred host plant is the invasive weed, kudzu.  No one knows how it got here, but like many invasive pests it made itself at home quickly.  Highly mobile, within a year the kudzu bug had spread to 60 north and central Georgia counties.  Two years later every county in the state had them.

Last week Texas became the 14th state with verified populations of kudzu bug.  Sharp-eyed county Extension agent Kim Benton reported kudzu bugs from a home garden in Rusk, TX, south of Tyler. The bugs were clustered on eggplant and other vegetables before being transplanted into the garden.

Description and damage

It is hard to mistake kudzu bug for anything else.  The bug is beetle-like in appearance with a unique, four-sided, ovoid shape.  It is greenish-brown and shiny, up to 1/4 inch-long (3.5-6 mm).  It uses its piercing/sucking mouthparts to feeding on the sap of kudzu and other legumes.

For soybean farmers and vegetable growers kudzu bug is another pest to battle. The bugs overwinter close to kudzu, their favorite food in the spring.  But in summer they move into soybeans where they can cause significant yield reductions. To a lesser extent they feed and reproduce on sweet peas, snap beans, cowpeas, lima beans and wisteria.  It may be seen on other plants as well, where it gathers temporarily, usually to move on in a day or so.


Is it a good bug?

Anyone familiar with the weed kudzu will be excused for thinking that having kudzu bug might be a good thing.  After all, one of the reasons kudzu is such a horrible weed is that few things eat it.  Wouldn't it be good to have an insect to keep kudzu in its place?

That's what the good folks in Georgia hoped.  But according to Georgia extension entomologist Phillip Roberts, their optimism didn't last.  "The first years we saw what we thought was a lessening of the kudzu problem.  Other weeds seemed to be competing more effectively with the kudzu."  But after a year, he said, the kudzu seemed unfazed.  "There has not been any noticeable decline in kudzu growth since the beetle moved in."

A (minor) crossover pest

Kudzu bugs cover the eave of a home in Georgia. Photo by
Dan Suiter.
Kudzu bug is one of very few agricultural pests that are structural pests as well. Problems in Georgia with kudzu bug are mostly restricted to homes near kudzu patches and soybean fields (rare) in Texas.  According to Georgia extension entomologist Dan Suiter, unlike the multicolored Asian lady beetle, kudzu bugs are attracted to buildings in the fall but rarely come indoors. "We never really see them getting inside," he said.

Nevertheless, expect that some homeowners will be upset over thousands of bugs clustering on the outside of their homes, especially on white-painted gutters, siding and around windows. Also, the bugs have an odor and secrete a staining fluid when disturbed.

Kudzu bug activity around structures is most noticeable in the fall.  This is when bugs from nearby kudzu are seeking shelter and are attracted to homes. 

How bad?

It's yet to be seen whether kudzu bug will become a noticeable pest in Texas, but indications from Georgia suggest it will not be a serious long-term pest.  Because kudzu is less prevalent in Texas than Georgia and other southern states, the bug is likely to occur only in east Texas, and populations limited to start with. But at least two egg parasitiods (egg predators) and a fungus called Beauveria bassiana, have severely reduced the kudzu bug problem in Georgia and most southern states. After being overwhelmed with calls the first five year after the bug's discovery, today Suiter says he "doesn't see more than 20 bugs a year" brought into his office.

Vegetable gardeners in counties with kudzu may be more bothered. Edamame, peas or other beans are susceptible to these bugs and may require treatment.

Control

If you are called on to manage kudzu bugs around a home, here are a few tips:

  • Focus on the outside of the building when controlling kudzu bugs--few bugs will be indoors, though caulking and sealing will also help in that regard.  
  • Pyrethroid insecticides are generally effective against kudzu bugs.  Bifenthrin and lambda-cyhalothrin are especially good in crop situations, according to Roberts.  Suiter said his research shows Alpine WSG (dinotefuran) also works well and has the added advantage of quickly killing the bugs, in seconds, eliminating the chance for unsightly aggregations to occur. 
  • Look for, and treat, any crack or crevice where bugs are aggregating. Examples include: gaps behind siding and around windows and doors; high places (such as around soffits, fascia boards and gutters); even loose bark on nearby trees.
  • If kudzu is present outside the home, use a herbicide to remove it, preferably during the spring or summer.  This can help reduce the numbers of bugs coming to the outside of the home in the fall.

If you find what you believe are kudzu bugs we would love to see a clear photo.  Also save specimens to bring to your county Extension office for official confirmation.  This can help us track the spread of kudzu bug within the state.