Thursday, May 29, 2014

A bug by any other name...

A stink bug belongs to the suborder
Heteroptera and is an example of a
"true bug". All true bugs have piercing/
sucking mouthparts, and go through
a gradual form of metamorphosis.
Every student in their first college entomology class gets introduced to the major types of insects, among which is a relatively large group of insects known as heteropterans (formerly referred to as hemipterans). And any entomology professor worth their salt dutifully teaches every student the rule that heteropterans are the only insects that can be considered "true bugs". That's what I was taught, but like most of my fellow entomologists, I've never really known why. So today, when I was asked by a teacher...who had been asked by a 5th grader, I figured I needed to do some research. What I learned was interesting, and even has a very contemporary urban entomology connection.

In my experience Americans commonly use the term "bug" very loosely to mean any very small critter, insect or otherwise. In this way a spider can be referred to as a bug, or a pesky gnat as a bug. This doesn't bother me too much, but sometimes you sense a kind of superiority among some people who use the term "bug" this way. "I'll squash you like a bug!" Or, "It's just a buuug!"

And who in the industry has not been referred to as either "bug guy" or "bug lady" when showing up at a pest control account? Although I like bugs in general, and consider work associated with insects to be important and honorable, I never particularly cared for the name applied to my profession--perhaps because of the inferior connotations associated with bugs in many people's thinking.

It's interesting how language works on a word. The term bug has crept its way into a lot of other uses, including meaning germs that makes you sick, like the "flu-bug".  Or as the verb referring to the act of acting or being annoying, as in the complaint: "Stop bugging me!"

The first "real" computer "bug" is kept at the Smithsonian
National Museum of American History, though it is
not currently on display. 
Maybe one of the more interesting modern spin offs of the term bug comes from modern technology. Computer programmers often refer to a software problem as a "computer bug". Supposedly, the origin of this use of "bug" has historical roots in one of the earliest computer snafus (another word with an interesting WWII origin).  An early electro-mechanical computer, the Mark II, a predecessor of modern digital computers, stopped working one day and the problem was traced to a moth that had gotten stuck in a relay.

But how did the entomological form of the word bug get its start?  And why do entomologists get so hung up on folks who misuse the word to refer to something not technically a heteropteran?

It turns out that the term "bug" probably does have a semi-scientific origins connected to entomology. According to Carl Schaeffer, author of an article on heteropterans (Prosorrhyncha) in the Encyclopedia of Insects, the term "bug" comes from the old Middle English word bugge, which meant "spirit" or "ghost".  According to another favorite reference of mine, Roland Wilbur Brown's Composition of Scientific Words, the word may also be derived from the Welsh word bwg, for "hobgoblin", "spectre" or "sprite".  The word even shows up in some of Shakespeare's writings to refer to bogeymen or other terrifying forces.  Obviously the Welsh and the English were referring to the same thing... but what?

Were bed bugs the original bugge?
Shaeffer supposed that in earlier times when people woke up in the morning and discovered their skin covered in red itchy welts and blood on the bed, they naturally would assume that they had been visited by malevolent spirits, or bugges.  And as you've probably guessed, the welts experienced by sleepers in Merrie Olde England were not likely caused by wraiths or spirits, but by little flesh-and-blood insects that today we call bed bugs.  Presumably the more enlightened Englishmen and Welshmen quickly realized the true cause of nighttime welts and began referring to the insects themselves as bugges.  And eventually, by extension, all relatives of bed bugs were also called bugs--though entomologists apparently decided to keep their use of the term to only the bed bug relatives, today's heteropterans.

So bed bugs are most likely the original bugge, or bwg, according to Schaeffer. The next time you hear someone seem to dismissively refer to bugs, or the profession devoted to pest control, consider that for many bugs still remain a scary part of life. What entomologists and PMPs do is help keep the bugs and other pests out.  That's a worthwhile service and, not surprisingly, one people will always pay for. And as Shakespeare himself might have put it, "What's in a name? That which we call a bug, would it by any other name... drum up as much business?" Perhaps not.

Tuesday, May 6, 2014

Temperature: the key to fire ant baiting

soil thermometer
A simple soil thermometer can tell you the optimal times
of year and times of day for fire ant bait application.
Fire ant baits are wonderful tools for managing fire ants.  They are relatively inexpensive, require little labor to apply as broadcast treatments, and are safe for both applicators and the environment.  One of the biggest limitations of baits is that they cannot be used all year round. Instead applications must be timed to periods when fire ants are actively looking for food, foraging in ant worker lingo.

Many years ago a researcher at Florida State University, named Sanford Porter, spent an entire year (three times a day, once a week) monitoring fire ants coming to little bits of hot dog. Along the way he carefully monitored surface and below-ground soil temperatures, relative humidity, time of day, soil moisture, rainfall, and air temperature.  Porter found that by far the best predictor of fire ants foraging (and thus, when they are most likely to find and collect bait) was when the temperature of the soil at 2 cm (a little less than an inch-deep) was between 72 and 97 degrees F.

It makes sense that fire ants would be most sensitive to soil temperatures at this depth, as this is about how deep fire ants travel in their foraging tunnels, where they travel 90% of the time.  In Porter's study, fire ants nearly always found baits when the soil temperature was in the favored range.

This morning and afternoon I went outdoors and took the soil temperature in the lawn surrounding my office in Dallas, TX.  The temperatures at one inch averaged between 74 and 82 degrees, in morning and afternoon. This is the sweet spot for fire ants, and indicates that all day today would be a great time to use fire ant baits.

Typically we suggest fire ant bait applications in north Texas be limited to the months of May through September.  This ideal baiting time will vary from one location to another, but the soil temperature rule of thumb should be consistent.  If you're not sure when to apply fire ant baits, check the soil temperature with a metal temperature probe.

Daily temperature fluctuations

Besides time of year, soil temperature is also influenced by time of day. Right now, on the grounds surrounding my office, anytime during the day would be a good time to broadcast fire ant bait. But as any seasoned Texan will tell you, there's a mighty big difference in temperatures between May and July.  In July soil temperatures, even at one inch-depth, soar well over 100 degrees, effectively shutting down most fire ant foraging during the day.

The best time to apply fire ant bait during the summer months is late in the day, in the evening. Bait applied in the morning hours, even when soil temperatures are still favorable, will quickly be exposed to high temperatures and high UV intensity, both of which are likely to render bait less palatable to ants.  By applying bait late in the day, it will be available to fire ants during their most favored time for foraging, throughout the night.

For more information about baiting for fire ants, see our publications on Managing Imported Fire Ants in Urban Areas and Broadcast Baits for Fire Ant Control.