Insect Perceptions, Irrelevant or Important

“IT WAS THE BUTTERFLIES, my people say, who brought the first human babies to their feet,” writes Canadian Richard Wagamese in “Butterflies Teachings,” an essay touching on “what’s called Enendamowin, or Ojibway worldview” in his brilliant collection, One Native Life. “Before that, the New Ones sat in innocence beneath a tree, watching the world around them with wonder. But Creator had planned more for them. Their destiny called for them to move throughout the world. These human babies were meant to walk upon their two legs, and as long as they sat under that tree their destiny could not be fulfilled…The air seemed to tremble with butterflies. The human babies were entranced. Each time they tried to snare a handful of colour, the cloud drifted away. They stretched their arms higher. They thrust out their hands. But it was to no avail. When the butterflies danced just out of reach a final time, the New Ones lurched to their feet and raced after them across the meadow. The Animal People celebrated quietly, then returned to their dens and burrows and nests. The human babies never caught those butterflies, but they kept on running, right into the face of their destiny…”

Quite a different worldview from Prague and Eastern Europe, where Franz Kafka’s famous novel Metamorphosis begins: “As Gregor Samsa awoke one morning from uneasy dreams he found himself transformed in his bed into a gigantic insect.” According to the “wall notes” in the exhibit “Disguise: Masks & Global African Art” at the Fowler Museum at UCLA, Kafka’s words inspired South Africa artist Walter Oltmann. Among neon masks, dancing mask videos and sculptured African animals wearing masks are Oltmann’s large anodized aluminum and brass wire caterpillars in the midst of “transformation and change” (metamorphosis) and fashion sketches titled “Beetles & Suits.” The suit coats are gracefully curving, shell-like beetle elytra (outer wing covers) fashionably topped off with the latest antennae, and looking both business-like and sci-fi out of Star Wars or Star Trek at the same time. I can easily imagine a cell phone age makeover of The Beatles’ Sgt. Pepper’s Lonely Hearts Club Band regalia and long hair with “beetle suits” and high-fashion antennae. Perhaps too much entomology affects the psyche. Oltmann writes that “spending an inordinate amount of time on making something that is usually considered insignificant like an insect, does make us look differently at them.” He says it “speaks of neither this nor that,” but I’m not so sure.

Insect observations appear in haiku by Japanese master Matsuo Basho, whom I think of as the late 1600s slightly more refined counterpart of 20th century Los Angeles poet Charles Bukowski, who was too busy with “other interests” to notice beetles, flies, mosquitoes and roadside weeds. In Moon Woke Me Up Nine Times: Selected Haiku of Basho, translator David Young writes: “Odd numbers predominate; a dance is occurring, and each third of the poem is a turn, a gesture, a refining or revelation… The poem seems to end almost as soon as it has begun, a small flash of lightning…A more literal version of the haiku cited (below) would be something like: What can save your life? / one leaf, with an insect / sleeping on its journey… the journey, which refers to a Chinese story that Basho’s readers would know but that is largely meaningless to English readers…‘Basho mash-ups,’ I have sometimes called my versions”:

One insect
asleep on a leaf
can save your life

Perhaps Basho was thinking of medicinal silkworms slumbering on mulberry leaves, or perhaps his mind was journeying among high mountains where ghost moths metamorphose with fungi into plant-animal hybrids that have been used in Asian medicine for centuries. David Young says about haiku: “They love to startle, first the writer and then the reader. As though a hummingbird were to land suddenly on your resting arm. It is the way the world so often surprises us.”

A haiku by Los Angeleno Mark Jun Poulos, whose observation of the seemingly mundane urban habitat nagged at me long after I thought I had dismissed its ordinary elements from consciousness:

restroom sink-—
ladybug cooling off
in a drop of water

What nagged at me was water, a vital ingredient of life, which as hard sprays of rain washes away pesky mites and aphids that are ladybug prey. Water (H2O) is also a missing ingredient in most ecological studies of interplanting, a habitat diversity strategy designed to boost populations of lady beetles and other beneficial insects providing natural pest control. Australian grape vineyards and California lettuce fields have had some success interplanting blooming rows of sweet alyssum to provide pollen, nectar and alternative prey for ladybugs, lacewings, hover flies and other beneficial species consuming aphids and other pests. Sweet alyssum is also host to micro-wasps helping Michigan asparagus growers by parasitizing leafmining pest insects, Amanda Buchanan of Michigan State University reported at the Entomological Society of America (ESA) annual meeting in Minneapolis. But if habitats are missing water, then perhaps lady beetles, which do not puncture plants to drink fluid, will leave to find restroom sinks, puddles or other water sources. Perhaps, like providing water bowls for pets, something similar needs to be researched as part of biological control habitat alternatives. Though I would draw the line at alcoholic drinks, except perhaps beer in snail and slug traps. Another urban haiku observation by Mark Jun Poulos:

sultry afternoon—
wasp hovers over a whiskey bottle
held by a drunk bum

Ethanol or ethyl alcohol, by percentage the main chemical component of distilled whiskey, should not be abused, nor perhaps should it be so heavily subsidized as a biofuel, as that incentive exacerbates huge landscape changes measurable as reduced biodiversity. At Synergies in Science, a rare Minneapolis gathering of the ESA, American Society of Agronomy, Crop Science Society of America and Soil Science Society of America, the diminishing biodiversity of a Midwest USA with 21% less wheat, 16% less hay and much more GMO corn to distill into ethanol motor fuels was as hard to ignore as a drunk with a whiskey bottle on an urban bench. Jonathan Lundgren of the USDA-ARS in Brookings, South Dakota said we need to get away from our “very pest-centric approach” and adopt a more holistic biological network approach. Instead of a Midwest saturated with pesticides to grow GMO corn to distill into fuel tank ethanol, something as seemingly simple as adding biodiversity via cover crops amongst the corn rows could produce enough soil biocontrol of corn rootworm to eliminate wasteful neonicotinoid seed treatments whose honey bee and beneficial insect friendliness is being hotly debated. Karen Friley of Kentucky State University reported at the ESA that something as seemingly simple as native plant border rows around sweet corn fields “provide microclimates in the form of moderated temperatures, which offer shelter” for numerous natural enemies controlling corn pests.

Curiously enough, ethanol (alcohol) like that in whiskey bottles and vehicle fuels also attracts pine beetles and ambrosia beetles considered destructive forest, landscape, street tree and nursery pests. Perhaps more curiously, the very trees being attacked are producing the ethanol and releasing it into the atmosphere when stressed (e.g. by drought or flood), decaying or dying. Trees may look perfectly healthy on the outside, but inside the tree is another story, because ethanol emissions are signs of sickliness and ill health. Chemical ecologist Christopher Ranger of the USDA-ARS in Wooster, Ohio said it is a real problem, for example, when nursery seedlings are used to replant spruce forests or with dogwoods, magnolias, pines, etc. in nurseries, backyards, along streets, etc. It is definitely ecology, as the ethanol is luring in the beetles to help “recycle” the trees back into the soil as nutrients.

I liked Ranger’s reasoning: Find the tree equivalent of driver breathalyzer tests as a beetle-attack early warning system. SCRAM wrist bracelets worn by offenders for transdermal drug and alcohol detection were tested, but were not sensitive enough; taking a week to detect low tree ethanol exhalations, whereas beetles detect a few parts per million of alcohol and get to trees almost on day one. The solution was a portable ethanol monitoring device with a detector tube and a plunger to pull in air samples; developed using Japan’s Gas Tech industrial gas leak detection technology for quick detection of “inebriated” trees.

So, which is more startling and surprising: art, haiku or entomology?

Strange brew: September 17, 2015 daylight turning to dark, caught in one of those infamous, almost proverbial L.A. traffic jams at a freeway underpass on Church Lane transitioning from Sunset Blvd to Sepulveda Pass on my way past the Getty Museum to Mulholland Drive, listening to the Moody Blues Live at Red Rocks, going nowhere. Haiku and fireflies flashing internally, and externally the blinking side turn lites and red back brake lights suddenly and surprisingly metmorphosed into synchronous fireflies, albeit of a mechanical or robotic nature:

Tail and Turn Lights
Flashing like Synchronous Fireflies
In the Los Angeles Traffic Jam

 

Food Sweetener Safely Slays Insects

CERTAIN SUGARS CONSIDERED SAFE as sweeteners in the human food supply can double as environmentally-friendly pest remedies, and even make biological control of insects by beneficial fungi more practical for households, farms and gardens. Considering that caffeine from coffee grounds can be used against deadly dengue mosquitoes and that a variety of traditional herbs can blast away bed bugs, insecticidal sugar compounds should come as no surprise. Perhaps the only remedy more surprising is that rain water or simulated rain sprays from hoses or irrigation equipment can safely wash away pests with no toxic pesticide residues to worry about in the environment.

Using sugars directly to slay insects is somewhat unusual. However, sugars are commonly used as attractants, for instance to lure fruit flies, moths or ants to baits and traps both for population control and as a survey method or monitoring tool. California citrus growers have a long history of using sugar sprays as an IPM (integrated pest management) strategy to lure fruit-scarring citrus thrips to organic or botanical formulations of ryania (“from woody stem and root materials of plants of the genus Ryania”) or sabadilla (alkaloids from seeds of a lily bulb, Schoenocaulon officinale). “INTEGRATED PEST MANAGEMENT implies that techniques used to manage one pest species should not disrupt techniques used to manage other pests of the same crop,” wrote J.D. Hare and Joseph Morse in the Journal of Economic Entomology. “In citrus pest management in California, this situation is well illustrated in the choice of pesticides for the management of one major pest, citrus thrips, Scirtothrips citri (Moulton), without disruption of several effective biological control agents of the other major pest, California red scale, Aonidiella aurantii (Maskell).”

That sugars can be lethal to pests and be a source of environmentally-friendly pesticides is not exactly intuitive. “Potential of the non-nutritive sweet alcohol erythritol as a human-safe insecticide” was the strangely intriguing title of Drexel University’s Sean O’Donnell’s presentation at the Entomological Society of America (ESA) annual meeting. Many of the details were previously published in PLoS ONE, an open access journal, and in part because of the origins of the research in a grade school science project by one of the researcher’s sons, aspects of the story have been widely reported in various media. “Erythritol is a zero-calorie sweetener found in fruits and fermented foods,” summarized Lauren Wolf in Chemical & Engineering News, and “is Generally Recognized As Safe by the Food & Drug Administration and has been approved as a food additive around the globe.”

“Many pesticides in current use are synthetic molecules such as organochlorine and organophosphate compounds,” and “suffer drawbacks including high production costs, concern over environmental sustainability, harmful effects on human health, targeting non-intended insect species, and the evolution of resistance among insect populations,” write the researchers in PLoS ONE. “Erythritol, a non-nutritive sugar alcohol, was toxic to the fruit fly Drosophila melanogaster. Ingested erythritol decreased fruit fly longevity in a dose-dependent manner, and erythritol was ingested by flies that had free access to control (sucrose) foods in choice and CAFE (capillary feeding assays) studies…

“We initially compared the effects of adding five different non-nutritive sugar substitutes (Truvia, Equal, Splenda, Sweet’N Low, and PureVia,” wrote the researchers in PLoS ONE. “Adult flies raised on food containing Truvia showed a significant reduction in longevity…We noted that adult flies raised on food containing Truvia displayed aberrant motor control prior to death. We therefore assayed motor reflex behavior through climbing assays…Taken together with our longevity studies, these data suggested some component of the non-nutritive sweetener Truvia was toxic to adult Drosophila melanogster, affecting both motor function and longevity of this insect…

“Our initial analysis of sweeteners included two sweeteners that contained extracts from the stevia plant, Truvia and Purevia. While adult flies raised on food containing Truvia showed a significant decrease in longevity compared to controls, this was not the case for flies raised on Purevia. These data suggest stevia plant extract was not the toxic element in these sweeteners. Purevia contains dextrose as a bulk component, while Truvia contains erythritol as a bulk component…To determine if erythritol was the toxic component of Truvia, we repeated our longevity studies on food containing equal weight/volume (0.0952 g/ml) of nutritive sugar control sucrose, and non-nutritive sweeteners Truvia, Purevia, and erythritol. We assured the flies were successfully eating the foods containing these sweeteners through dye labelling the food with a non-absorbed blue dye (blue food), and visual confirmation of blue food present in fly abdomens and proboscises daily…The average percentage of blue abdomens throughout the study were 97.46%.”

“These data confirm all treatment foods (including Truvia and erythritol treatments) were consumed by adult flies, and suggest mortality was not due to food avoidance and starvation…A large body of literature has shown that erythritol consumption by humans is very well tolerated, and, indeed, large amounts of both erythritol and Truvia are being consumed by humans every day throughout the world. Taken together, our data set the stage for investigating this compound as a novel, effective, and human safe approach for insect pest control. We suggest targeted bait presentations to fruit crop and urban insect pests are particularly promising.”

Interestingly, a few decades ago UK researchers found that the sweeteners (sugar alcohols; polyols) erythritol, glycerol and trehalose rendered more effective several insect biocontrol fungi, Beauveria bassiana, Metarhizium anisopliae and Paecilomyces farinosus. These insect-killing fungi need a relative humidity (RH) near 100% for germination of their conidia (seed-like propagules). “Conidia with higher intracellular concentrations of glycerol and erythritol germinated both more quickly and at lower water activity,” wrote UK researchers J.E. Hallsworth and N. Magan in the journal Microbiology. “This study shows for the first time that manipulating polyol content can extend the range of water availability over which fungal propagules can germinate. Physiological manipulation of conidia may improve biological control of insect pests in the field…Although fungal pathogens have been used to control insect pests for more than 100 years, pest control has been inadequate because high water availability is required for fungal germination.”

Curiously, erythritol and glycerol, besides being sweetening substances, also function as antifreeze compounds. Certain Antarctic midges, known as extremeophiles for living in an ultra-cold habitat, ingest and sequester erythritol from their food plants; and as antifreeze it protects the adult flies from freezing. Indeed, many mysteries remain. Besides being found in green plants like stevia and in lower amounts in fruits, erythritol is found in certain mushrooms, lichens and algae. Human and animal blood and tissues apparently have low endogenous levels of erythritol; and erythritol is a yeast fermentation product (hence in sake, beer, wine). In human medicine, erythritol has been used for coronary vasodilation and treating hypertension; and according to Japanese microbiologists, erythritol ingestion may mean fewer dental cavities (caries) than sucrose sugar.

Silicon Bed Bug Weaponry

BED BUGS CAN be spiked and trapped by tiny spears like leaf hairs, and can become dehydrated or dessicated and rendered harmless by certain forms of silicon, the second most abundant element in planet Earth’s crust (28%) after oxygen (47%). That silicon can be the bane of bed bugs is indeed odd when one considers that silicon permeates our world from beach sands, opals, agates and quartz crystals to sandpaper, semiconductors, glasses, ceramics, optical fibers and cosmetic products. Indeed, the famous French scientist and silkworm entomologist, Louis Pasteur, whose name has become synonymous with the germ theory of medicine, predicted silicon’s eventual service in human medicine; though Pasteur was probably not thinking along the lines of silica gels and desiccant diatomaceous earth dusts as remedies for the 21st century’s worldwide medical plague of bed bugs.

Despite its commonness in nature and the human environment and potential uses in human medicine, the use of silicon products comes with caveats to users, who might want to wear sufficient protective clothing and respirators to avoid inhaling the products. Strangely enough, that much maligned metabolic waste product, carbon dioxide, which along with sunlight is essential to photosynthesis and life on planet Earth, is perhaps a safer component (e.g. as a lure or attractant) when integrated into bed bug traps. Food grade diatomaceous earth made from freshwater diatoms is considered relatively nontoxic; whereas filtering grade diatomaceous earth (e.g. the type used for swimming pool filters) is a crystalline form with inhalation toxicity.

“Louis Pasteur (1822-95) said that silicon would prove to be a treatment for many diseases and in the first quarter of the twentieth century there were numerous reports by French and German doctors of sodium silicate being used successfully to treat conditions such as high blood pressure and dermatitis,” wrote British chemist John Emsley in his superb compendium, Nature’s Building Blocks (An A-Z Guide to the Elements). “By 1930, such treatments were seen to have been in vain and the medication fell out of favor. So things rested, until the discovery that silicon might have a role to play in human metabolism, and then followed suggestions that it could have a role in conditions such as arthritis and Alzheimer’s disease, but no new treatment based on these suggestions has yet emerged. Meanwhile, silicon continues to be linked with a disease of its own: silicosis. Miners, stone-cutters, sand-blasters and metal-grinders develop this lung condition which is a recognized occupational disorder caused by the inhalation of minute particles of silica…” Symptoms include coughing, wheezing and shortness of breath; a more aggressive form of silicosis associated with certain types of asbestos can develop into lung cancer and has been a rich source of litigation for occupational exposure in the USA.

While silica products should be used sparingly (a caution that should also apply to most sprays) or not at all by some people (e.g. existing respiratory problems; perhaps seek a medical opinion before using), they might prove for many others the tipping point for winning the bed bug war as part of an integrated approach that controls bed bugs (many of which are pesticide resistant) using a multiple arsenal of weapons including herbal oils, clutter reduction, heat, sealing crack and crevice harborages, traps, pheromones, carbon dioxide, vacuuming under baseboards, etc.

At the 2014 Entomological Society of America (ESA) annual meeting, Kyeong-Yeoll Lee of South Korea’s Kyungpook National University (Daegu) reported that silica in the form of diatomaceous earth (Perma-Guard(TM) or Fossil-Shell(R)) acted as a synergist when heat (hot air) fumigations substituted for chemical fumigants such as methyl bromide. Though the test insect was Indian meal moth, a worldwide pest of stored grain and many other packaged agricultural products, it would not be surprising to find that heat treatments combined with silica products like diatomaceous earth will also prove efficacious and perhaps also synergistic against bed bugs. Indeed, heat treatments may induce bed bugs to move around more, which could hasten contacting diatomaceous earth and water loss.

At the same 2014 ESA meeting, Virginia Tech (Blacksburg, VA) researcher Molly Stedfast provided some impressive results via the time-consuming process of first educating apartment residents about bed bugs and then painstakingly vacuuming along baseboards to suck up as many bed bugs as possible before applying the silica products under the baseboards to further reduce bed bug populations. This integrated (IPM; integrated pest management) approach required quite a bit of manual labor, as furniture had to be moved to gain access to the baseboards before vacuuming and then applying silica gel or dust products.

Stedfast tested two silica products, Mother Earth(TM) D, a highly-absorptive desiccant dust made from 100% freshwater diatomaceous earth, and CimeXa(TM) Insecticide Dust, a 100% amorphous silica gel. The silica dust or gel injures the insect cuticle (outer protective “skin”), letting water leak out and leading to dehydration (providing relative humidity is not extremely high, above 81%; and free water is unavailable). Both the diatomaceous earth and silica gel products were “very effective at killing bed bugs even at 10% of the label rate.” Going above the label rate was a waste of resources, as only so much product can contaminate the bed bugs. Bed bugs can die within 24 hours of contacting the silica products, but air currents that blow the dusts around can be a problem; also the products need to stay moist and not dry out to be effective. Among Stedfast’s biggest headaches is the application equipment, which was not very robust.

The patent literature reveals that inventors such as Roderick William Phillips in Vancouver are working on improved spray apparatuses for applying diatomaceous earth: “There is disclosed a spray apparatus for holding contents comprising diatomaceous earth and a compressed propellant for propelling the diatomaceous earth. There is also disclosed use of diatomaceous earth to control a population of bedbugs…diatomaceous earth, a naturally occurring siliceous sedimentary rock that includes fossilized remains of diatoms. However, known methods of applying diatomaceous earth can be cumbersome. For example, known methods of applying diatomaceous earth may undesirably require handling the diatomaceous earth, for example to transfer the diatomaceous earth from a container not having an applicator to a separate applicator apparatus. Also, known applicator apparatuses may apply diatomaceous earth unevenly, which may be wasteful or ineffective. In general, known methods of applying diatomaceous earth may be sufficiently complex so as to require professional involvement, which may undesirably add to cost and delay of bedbug treatment. Also, numerous types of diatomaceous earth are available, and different types of diatomaceous earth vary widely and significantly from each other. It has been estimated that there are approximately 100,000 extant diatom species…and may vary widely and significantly in size and shape across a very large number of diatom species…”

At the University of British Columbia (Vancouver), Yasmin Akhtar and Murray Isman demonstrated that both diatomaceous earth and herbal or botanical compounds such as neem, ryania and rotenone are to varying degrees transported by adult bed bugs and contaminate other adults and younger bed bug nymphs. “Our data clearly demonstrate horizontal transfer of diatomaceous earth and botanical insecticides in the common bed bug,” said Akhtar and Isman. “Use of a fluorescent dust provided visual confirmation that contaminated bed bugs transfer dust to untreated bed bugs in harborage. This result is important because bedbugs live in hard-to-reach places and interaction between conspecifics can be exploited for delivery and dissemination of management products directed at this public health pest…This result is important because bedbugs live in hard-to-reach places (cracks, crevices, picture frames, books, furniture) and as such interaction between the members of the colony can be exploited for delivery and dissemination of control products.”

At the 2014 ESA annual meeting, Akhtar suggested protecting travelers and suppressing bed bug transit by building diatomaceous earth into luggage, mattresses and fabrics. Diatomaceous earth provided 96% repellence; bed bug mortality was zero at 24 hours, but 93% after 120 hours. Diatomaceous earth could also be applied to box springs, dressers and headboards, and under carpets and inside drywall. A diatomaceous earth aerosol provided 81% bed bug mortality at 30 days, and was still active and being transferred from dead bed bugs to live bed bugs.

Diatom species mined for diatomaceous earth are stunning in their architectural variety and beauty. Ultimately, the silicon secrets of living diatoms has the potential to transform “the manufacture of siloxane-based semiconductors, glasses, ceramics, plastics, elastomers, resins, mesoporous molecular sieves and catalysts, optical fibers and coatings, insulators, moisture shields, photoluminescent polymers, and cosmetics,” wrote UCSB marine scientist Daniel E. Morse. “The manufacture of these materials typically requires high temperatures, high pressures or the use of caustic chemicals. By contrast, the biological production of amorphous silica, the simplest siloxane [(SiO2)n], is accomplished under mild physiological conditions, producing a remarkable diversity of exquisitely structured shells, spines, fibers and granules in many protists, diatoms, sponges, molluscs and higher plants. These biologically produced silicas exhibit a genetically controlled precision of nanoscale architecture that, in many cases, exceeds the capabilities of present-day human engineering. Furthermore, the biological productivity of siloxanes occurs on an enormous scale globally, yielding gigatons per year of silica deposits on the floor of the ocean. Diatomaceous earth (composed of the nanoporous skeletons of diatoms) is mined in great quantities from vast primordial deposits of this biogenic silica.”

Impaling Bed Bugs on Tiny Spikes (Leaf Hairs)

KIDNEY BEAN LEAF hairs, an ancient Balkan folk remedy to ameliorate bed bugs biting like vampires in the nighttime and wee morning hours, are in essence medieval warfare pikes barbarically impaling bed bugs resistant to 20th and 21st century synthetic pesticides. The resurrection of kidney bean leaves from Balkan folklore is a measure of human desperation, and an example of an IPM (Integrated Pest Management) strategy combining multiple weapons and tactics to fight this modern-day plague. According to The Journal of the Royal Society Interface, a modern offshoot of the one of the earliest medieval gatherings (mid-1600s) of natural philosophers, scientists and scientific craftsmen (instrument makers) into an official organization, those Balkan peasants knew a thing or two about fighting pestilence with “primitive” botanical remedies. Ultimately, bed bug-impaling bean hair “swords” or fabricated replicas will be combined in IPM strategies with other tactics, including ancient Ayurvedic Asian herbal remedies like neem tree oils (see previous blog).

You are not alone in being plagued by bed bugs: According to the journal Medical and Veterinary Entomology (Davies et al., 2012) there are “over 4 millennia of recorded narratives dating back to medieval European texts, classical Greek writings and the Jewish Talmud” and “archaeologists excavating a 3550-year-old workmen’s village at el-Amarna in Egypt found fossilized bed bug remains.” Plus bed bug “Females lay one or two eggs every day, and each female may lay 200–500 eggs in her lifetime, which may be 6 months or longer.” Modern heated buildings with lots of cracks, crevices and hiding places are even more comfortable for bed bugs than the ancient unheated buildings and caves of our ancestors.

The search for botanical remedies is perhaps equally ancient. Sir Francis Avery Jones, writing in the Journal Of The Royal Society Of Medicine (v. 89, Dec. 1996): “In the Stone Age the hunter-gatherers have learnt by hard experience…Over the eons they could have recognized plants which dulled pain, induced sleep, healed wounds, or poisoned animals or their enemies like wolfsbane…In Iraq there is a well-preserved grave of Neanderthal man, dated to some 60,000 years ago, with grains of flower pollen thickly scattered around the bones. The pollen came from eight different species still grown in Iraq today, some having recognized medicinal uses…Very early documents from China, Egypt, Sumaria and India describe the uses of anise, mustard, caraway, mint, saffron, thyme, cardamom, turmeric, cloves and pepper. The herbals reached their peak in the first century AD when the Greek physician Dioscorides assembled his vast De Materia Medica, recording the name, description, habit and medical use of some 600 plants.”

Bean leaves in comparison are a relatively modern bed bug botanical, a variant on the Tudor England practice of covering floors with pest-repellent (e.g. versus fleas, flies, plague, gaol fever/typhus) strewing herbs for their uplifting aromatic properties (e.g. rosemary, woodruff, various mints, box, lavender, santolina, hyssop, balm, cleavers, costmary, marjoram, meadowsweet, tansy). Queen Elizabeth’s use of meadowsweet leaves and flowers was described in The Herbal or Generall Historie of Plantes (1597) by John Gerard: “leaves and floures of meadowsweet farre excell all other strewing herbs for to deck up houses, for the smell makes the heart merrie and joyful and delights the senses.”

The Balkan remedy of bed bugs becoming entangled in hooked bean leaf hairs was written about by someone named Bogdandy in 1927 in the journal Naturwissenschaften and then again in 1943 by the USDA’s Henry Richardson in the Journal of Economic Entomology. According to a 2013 issue of The Journal of the Royal Society Interface, whose authors included Catherine Loudon of the University of California Irvine, who talked about the subject at the Entomological Society of America (ESA): “Historical reports describe the trapping of bed bugs in Balkan countries by leaves from bean plants strewn on the floor next to beds. During the night, bed bugs walking on the floor would accumulate on these bean leaves, which were collected and burned the following morning to exterminate the bed bugs.”

Fire, burning bean leaves that have “hooked” or “trapped” bed bugs, might be considered an extreme and specialized form of pest control heat treatment to be practiced with extreme caution. But compared to combating blood-sucking (vampirism) and werewolfism (Lycanthropy) in Hollywood B-movies, who’s to say. YouTube has videos showing bed bugs getting snagged by bean leaf hairs, and a simulation indicating that real bean leaves are still better than synthetic fabrics fabricated to mimick bean leaves. Kidney bean varieties are best for impaling passing bed bugs, and easy to use around a bed. But some lima bean varieties and small passion flower leaves also work, said Loudon. Interestingly, like computer chips, bean hairs that snag bed bugs best are toughened with silicon, unlike synthetic fabric hairs so far fabricated from substances like dental molding.

But given enough time, I would expect researchers in some dark Transylvanian lab in the Vampire District or in some light-splashed lab with surfboards along Frankenstein Row on the southern California coast to focus their scanning electron microscopes under high and low vacuums and eventually patent and reveal to the world nano-fabric silica hairs of a monstrous nature (to bed bugs) that can protectively surround sleepers and trap bed bugs before they bite. Or perhaps the genetic engineers will get there first with a carnivorous plant (the Venus Bed Bug Trap) for biocontrol. But if you’re keeping score, for most of human history, with some periods of remission, Team Bed Bug is still on top. In the meantime, pleasant dreams; and don’t let the bed bugs bite.

Bed Bug Herbal Remedies Work Well With Traps

THE NEEM TREE (Azadirachta indica), a medicinal mahogany tree (Meliaceae) native to arid broadleaf and scrub forests in Asia (e.g. India), has been used for over 4,000 years in Vedic medicine and has a heavy, durable wood useful for furniture and buildings because it is resistant to termites and fungi. Nonetheless, despite US EPA registration as a pesticide for crop and home use and a long legacy of neem seed oil use for cosmetics, shampoos, toothpastes and medicines in India, Ohio State University researcher Susan Jones could not find any households near her Columbus, Ohio, home willing to try neem in her bed bug control experiments.

“We had no study takers because of the regulatory requirements,” which scared off people, Jones told the Entomological Society of America (ESA) Annual Meeting. “You have to read page after page to residents about toxicity without being able to talk about the toxicity of alternative products” not as safe as neem. In October 2012, an empty house with bed bugs became available for research when its occupant opted to escape a bad bed bug infestation by leaving the infested home; and inadvertently transferred the infestation to their new home.

Jones monitored the empty house by placing in each room four (4) Verifi(TM) CO2 (carbon dioxide) traps and four (4) Climbup(R) Interceptor traps. Visual inspections revealed few bed bugs. On October 24, 2012, prior to neem treatments, 38 bed bugs were captured in Climbup(R) traps, indicating bed bug infestations only in the master bedroom and bed of the empty house. Eight Verifi(TM) traps captured 48 bed bugs in the dining room, guest room and master bedroom. As part of an IPM (integrated pest management) approach using multiple treatment tools: Electrical sockets were treated with MotherEarth(R) D diatomaceous earth; 3.67 gal (13.9 l) at a rate of 1 gal/250 ft2 (3.9 l/23 m2). Gorilla Tape(R) was used to seal around the doors and exclude bed bug movement from other rooms.

The neem seed oil product, Cirkil(TM) RTU, was sprayed in various places, including on books, backs of picture frames and cardboard boxes. Vials of the insecticide-susceptible Harlan bed bug strain were placed around the house for on-site neem seed oil vapor toxicity assays. Two days after spraying, bed bug mortality from neem seed oil vapors was highest in confined spaces; with 48% mortality in vials placed between the mattress and box spring, versus 28% mortality in open spaces. On Nov. 6, two weeks post-treatment, 123 dead bed bugs were vacuumed up and live bed bugs were detected in a second bedroom. Bed bug numbers were low because the monitoring traps were doing double duty, also providing population suppression by removing many bed bugs.

Herbal oils can also be combined with heat chambers at 50 C (122 F) or carbon dioxide (CO2) fumigation chambers to combat bed bugs. However, heat chambers are expensive, and CO2 fumigation with dry ice can pose handling difficulties and room air circulation issues, Dong-Hwan Choe of the University of California, Riverside, told the Entomological Society of America (ESA).

Herbal essential oils are useful against head lice, and in Choe’s native Korea clove oil from from the leaves and flower buds of clove plants (Syzygium aromaticum) is used in aromatherapy and as a medicine. Clove oil is rich in GRAS (Generally Recognized as Safe) compounds such as eugenol, beta-caryophyllene and methyl salicylate (sometimes called wintergreen oil), which are useful as vapors in control of insects and microbes. In dentistry, clove oil (eugenol) is widely used as an antiseptic and pain reliever.

Clove essential oils work faster in closed spaces or fumigation chambers (e.g. vials, Mason jars) than in open spaces. Essential oils are even slower to kill bed bugs when orally ingested. In experiments at varied temperatures, Choe placed 10 bed bugs in plastic vials with mesh tops. The vials were placed inside 900 ml (1.9 pint) Mason jars; filter paper treated with essential oils was placed on the underside of the Mason jar tops.

Herbal essential oils worked faster at higher temperatures. For example, methyl salicylate fumigant vapors provided 100% bed bug mortality in 30 hours at 26 C (79 F); 10 hours at 35 C (95 F); and 8 hours at 40 C (104 F). Eugenol vapors produced similar results; there were no synergistic or additive effects from combining eugenol and methyl salicylate. Choe told the ESA that his future trials will include: botanical oil granules; exposing bed bug-infested items to essential oil vapors; and checking for sublethal essential oil effects on parameters such as female bed bug reproduction.

Narinderpal Singh of Rutgers placed bed bugs on cotton fabric squares treated (half left untreated) with synthetic pesticide and herbal essential oil products: 1) Temprid(TM) SC, a mixture of imidacloprid and cyfluthrin (neonicotinoid and pyrethroid insecticides); 2) Ecoraider(TM) (Reneotech, North Bergen, NJ) contains FDA GRAS ingredients labeled as “made from extracts of multiple traditional herbs that have been used in Asia for hundreds of years for therapy and to repel insects;” 3) Demand(R) CS, which contains lambda-cyhalothrin (a pyrethroid insecticide); 4) Bed Bug Patrol(R) (Nature’s Innovation, Buford, FL), a mixture with the active ingredients listed as clove oil, peppermint oil and sodium lauryl sulfate.&&

Temprid(TM) SC and Demand(R) CS proved best on the cotton fabric test. In arena bioassays with Climbup(R)Interceptor traps, none of the four insecticides were repellent to bed bugs (i.e. repellency was less than 30%). Ecoraider(TM) was equal to Temprid(TM) SC and Demand(R) CS against the tough to kill bed bug eggs. Singh concluded that field tests of Ecoraider(TM) as a biopesticide were warranted.

Changlu Wang of Rutgers told the ESA that travelers might be protected from bed bug bites and bring home fewer bed bugs if protected by essential oil repellents, as well as by more traditional mosquito and tick repellents like DEET, permethrin and picaridin. Repellents are more convenient and less expensive than non-chemical alternatives such as sleeping under bed bug tents and bandaging yourself in a protective suit.

Isolongifolenone, an odorless sesquiterpene found in the South American Tauroniro tree (Humiria balsamifera), is among the botanicals being studied, as it can also be synthesized from turpentine oil and is as effective as DEET against mosquito and tick species. Bed bug arena tests involve putting a band of repellent around a table leg, with a Climbup(R)Interceptor trap below. If the bed bug falls into the trap, it is deemed to have been repelled from the surface above. In actual practice, the bed bug climbs up the surface and goes horizontal onto the treated surface and drops or falls off if the surface is repellent. Isolongifolenone starts losing its repellency after 3 hours; 5%-10% DEET works for about 9 hours. In arena tests with host cues, 25% DEET keeps surfaces repellent to bed bugs for 2 weeks. But isolongifolenone is considered safer, and Wang is testing higher rates in hopes of gettting a full day’s protection.

Hotels & Rooms Too Hot for Bed Bugs

HOT HOTEL ROOMS and hot dorm rooms are part of the bedbug buzz at the Entomological Society of America (ESA) annual meetings. There are even indications that hot air remedies can work well in combination with other bedbug control methods, including pesticides and dogs that sniff out bedbugs.

More companies are getting into commercial heat treatments for bed bugs. It seems a matter of practical application of the scientific data that heat can kill bedbugs, if you can figure out how to get the heat to where the bedbugs are hiding. Check out You Tube to see some companies in action using heat treatments against bedbugs, and read the comments (not everyone is convinced).

It is called integrated pest management (IPM) when you combine methods. KTLA News in Los Angeles has an amusing You Tube video combining dogs to sniff out bedbug pheromones with a propane heating device with a fan to cook cockroaches and bedbugs hiding out in rooms. Bed Bug Central TV (BBCTV) is also turning up the heat on bedbugs on You Tube. ThermaPureHeat has one of the best videos, with a Bakersfield heat fumigation job followed by a jazzy closing chorus of “don’t let the bed bugs bite ya.”

Roberto Pereira has been working on hot air fumigation treatments to kill bedbugs in University of Florida dorm rooms during the summer breaks between school years. Heat treatments have a long history of use in entomology (e.g. termites, stored product pests), but it takes some air circulation knowledge and skill.

Pereira and the University of Florida have come up with a short video of their heat chamber idea to disinfest furnishings: “Basically, we put all the furniture of the room at the center of the room, we create an oven around it by using insulation boards, and then inside the box, we put two heaters and fans so that the air is heated and it’s circulated within the box.”

Pereira also tested the combination of hot air fumigation plus “pest strips,” like what you find for sale in supermarkets and hardware stores, for use in EMPTY dorm rooms after all the students have gone home for the summer. You definitely do not want to breathe in the dichlorvos fumes from “DDVP Pest Strips,” particularly when the heat speeds up the chemical release. Though labeled for use at the rate of 1 strip per 900-1,200 cubic feet (25.5-34.0 m3) or no more than 2 strips per room, Pereira cautions that this treatment is for EMPTY rooms in which no one will be living for several weeks.

“DDVP is not something you should be breathing,” said Pereira, who noted that there is a 4-hour per day exposure limit. Indeed, buried in the pest strip label is the following warning: “HOUSEHOLD USES: Use only in Closets, Wardrobes, Cupboards and Storage Spaces. DO NOT USE IN AREAS OF A HOME WHERE PEOPLE WILL BE PRESENT FOR AN EXTENDED PERIOD OF TIME (e.g. Living Room, Family Room).”

Pereira’s work with the easily available pest strips was what is known in science as a “proof of concept” experiment. The idea being that if pest strips worked well with heat, a “softer” chemical, perhaps a botanical or herbal product, could be then be substituted. For scientific experiments, dorm rooms are ideal because they are identical modules. When you start getting into homes with furniture, where every room is slightly different, circulating hot air to kill bedbugs gets trickier.

Box fans placed behind space heaters were used in the Florida dorm room experiments. At 95-97 F (35-36 C), heat killed exposed bed bugs, but bed bugs in hiding (insulated vials) continued living and laying eggs. DDVP pest strips alone, with no heat, took 7 days to kill 100% of bed bugs. With fans circulating heat and pest strip poisons, bed bugs were killed in one day.

Thomas Jarzynka of Massey Services in Orlando, Florida, told the ESA that heat can penetrate walls to kill bedbugs missed by chemical treatments. Two 1,500-watt heaters were inadequate for a hotel room. Jarzynka recommends three 18,000-watt heaters. Besides being energy intensive, temperatures have to be monitored closely to avoid burning furnishings or surfaces. Heat treatments of hotel rooms are started at 7-8 a.m., and temperatures held at 120 F (49 C) for at least 4 hours (sometimes up to 8 hours). Wallboard probes are used to measure temperatures, as it is especially tough to circulate heat to kill bedbugs at carpet level in wall-floor junctions.

Heating a room to kill bedbugs is a bit of an art, combined with some knowledge of engineering and construction materials. Arrangement of room furnishings is critical to heat circulation by fans, said Jarzynka. Fans can be arranged to move hot air along an outer circle, direct heat to a central area, leave cool spots, etc. Rooms can be heated one section at a time, and furnishings can be moved or turned 360 degrees to avoid being burned by heaters.

Bedbugs are tough to get in their hiding places, even with chemicals. So heat treatments, if done right, make good sense. But you need to do your homework, if you want to make life too hot for bedbugs to bite.

Planet Moth

WITH 200,000 known species, Earth is almost Planet Moth. Only beetle species are more numerous. Moths have been denizens of Earth since prehistoric times, long before the ascent of man. Mostly nocturnal, secretive and nondescript, moths play a quiet ecological role, doing some vital pollination of plants and nourishing the food chain by feeding birds, bats, lizards, fish, frogs and many other critters.

Silkworm moths, domesticated as a crop on mulberry trees in China about 5,000 years ago, are famous in the textile industry. Clothes moths are infamous for feeding on garments, and have spurred herbal pest control innovations since ancient times. Humankind has sprayed billions of tons of synthetic pesticides against cotton bollworm moths, Indian meal moths, diamondback moths, cabbage loopers, leafrollers, leafminers, stemborers, codling moths, corn earworms, inchworms, armyworms, spruce budworms, gypsy moths and bagworms, to name but a few. However, alternatives like pheromones are becoming more widely used to monitor, trap, and confuse moths and prevent mating and egg laying (eggs hatch into caterpillars that eat, pupate and beget new moths).

Biocontrol by natural enemies, including birds, bats, toads, spiders and other insects, is part of the ancient planetary rhythm for controlling moths and maintaining global ecological balance. From Texas, Arizona, California and Mexico to China, Russia, Central America and Australia, microscopic Trichogramma wasps are among the most popular insectary-reared natural enemies released to stop moth egg hatching. Cotton growers escaping the pesticide treadmill have traditionally been big users of Trichogramma wasps. Tomatoes, corn, grapes, tree fruits, ornamental nurseries and many other crops also use Trichogramma, green lacewings and a wide array of other natural enemies purchased from Rincon-Vitova and other insectaries to lessen moth attacks and minimize pesticide use.

Of course, the moth wars are not all one-sided. Spray pesticides too often and moths become resistant. And moths can elude and make life challenging for their natural enemies. For example, many moth species respond to bat ultrasound echo-location signals with evasive aerial maneuvers and jamming signals. Moth immune systems may even encapsulate and prevent parasites from providing biocontrol. Each female of one fat Australian moth species can lay 18,000 eggs, the ultimate defense, essentially ensuring survival by sheer numbers.

Coffee Grounds for Mosquito Control

RECYCLE BIODEGRADABLE coffee grounds and simultaneously knockdown mosquitoes vectoring dengue, yellow fever, West Nile virus, malaria and other diseases. Hermione Bicudo at Universidade Estadual Paulista in Sao Paulo, Brazil, has been working towards that goal since the early 1980s. Mosquito control alternatives are needed, as mosquitoes are rapid, prolific breeders that rapidly develop resistance to pyrethroid, organophosphate and other types of insecticides.

Bicudo’s lab began studying caffeine effects on Drosophila fruit flies in the early 1980s. Drosophila fruit flies are a model insect widely used from the early twentieth century to unravel the mysteries of inheritance and genetics. Caffeine has been used relatively safely for centuries, and is found in medicines, cosmetics and food and beverages like coffee, tea, guarana and chocolate. Used coffee grounds are a ubiquitous waste product in modern caffeinated societies.

A resurgence of yellow fever mosquito, Aedes aegypti, in Brazil prompted Bicudo’s lab to test whether deleterious caffeine effects on Drosophila fruit flies (e.g. less frequent mating, less egg laying capacity, shorter life spans) might also slow mosquito population growth. Approximately four full soup spoons of used coffee grounds in a 250 mL glass of water killed 100% of aquatic mosquito larvae. This translated into fewer adult mosquitoes (the biting, blood-sucking stage) and less new mosquito egg laying (thus, lower mosquito populations over time). Used coffee grounds also have fertilizer value for plants, and can be dusted onto Bromeliads and other garden plants (possibly also puddles, ponds, tree holes, used tire breeding sites, etc.) where accumulated water forms potential mosquito breeding sites.

In contrast to other researchers, Bicuda’s lab found that caffeine solutions became more effective against mosquitoes with age. Day-old caffeine solutions took 20 days to kill 100% of mosquito larave; 25-day old caffeine solutions killed 100% of mosquito larvae in 1 day. Combined with elimination of mosquito breeding sites, used coffee grounds or caffeine solutions could prove very useful in IPM (integrated pest management) programs to slow pesticide resistance and reduce mosquito breeding.

Beating the Bed Bug Blues

“SUCH BUGS and goblins in my life,” said Shakespeare’s Hamlet during the medieval era when “bug” meant bed bug. Indeed, bedbugs have been part of the human condition from prehistoric times. By 400 B.C. the ancient Greeks were scratching bedbug bites and singing the Big Bed Bug Blues. Bat caves, bird nests and animal barns are the natural habitats supporting bed bugs and their goblin-like natural enemies like itch mites, assassin bugs, assorted ants, centipedes, and spiders.

Though bedbug biocontrol by the currently-known crop of natural enemies seems better left to the Batcave and more rustic outdoorsy habitats, natural ecological principles still apply in human dwellings. Contrary to the DDT-nostalgia (interestingly, lacking scientific citations) infesting Wikipedia, pesticides cannot substitute for human smarts in fighting bedbugs. Even in the heyday of DDT bed bugs were hard to kill and there was pesticide resistance, Clemson University urban entomologist Eric Benson told an Entomological Society of America (ESA) annual meeting. Indeed, overdoing pesticides is likely to kill natural enemies and stimulate outbreaks of new indoor pests (e.g. rat mites).

An integrated pest management (IPM) approach pits human ingenuity and a multiplicity of tactics against bedbugs. Shripat Kamble of the University of Nebraska told an ESA annual meeting of traditional bedbug remedies rememebered from a childhood in India: “People commonly used in the summertime heat treatment. Keeping the cot outside in the hot sun,” and shaking the bed so the bugs spilled onto bare ground hot enough to kill. “Another treatment that was commonly done was boiling water, and then pouring boiling water through all the hiding areas of the bed bugs…A lot of times it worked, and sometimes we still had problems.”

Nobody, not even the professionals, has a surefire remedy guaranteed to work against bedbugs every time in every household. Like Shakespeare and the ancient Greeks, bedbugs are likely to remain a part of the modern human condition.