A butterfly ballet
In the front window
White wings and black dots dancing on purple lantana
A butterfly ballet
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.
TURF is a $25 BILLION USA INDUSTRY, said Nastaran Tofangsazi of the University of Florida (Apopka, FL), a sex pheromone researcher looking to complement biocontrols like beneficial Beauveria bassiana fungi and Steinernema carpocapsae nematodes to control the browning and uneven grass growth caused by tropical sod webworm (Herpetogramma phaeopteralis) in Florida’s $9 billion worth of turfgrass. Also at the Entomological Society of America (ESA) annual meeting, Auburn University’s R. Murphey Coy noted that the USA’s 164,000 km2 (63,320 square miles) of turf is the USA’s most irrigated crop. Turfgrass irrigation consumes 300% more water than corn; plus 4.5 pounds (2 kg) of nitrogen per 1,000 square feet (93 m2).
Alabama is among the top USA turfgrass-producing states, and Auburn University researchers are looking to reduce turfgrass water, nitrogen and iron inputs by colonizing grass seeds and roots with easy to apply sprays of plant growth promoting rhizobacteria (PGPR). Blends of PGPR species such as Bacillus firmis, Pseudomonas and Rhizobium in turfgrass and cotton induce systemic resistance to pestiferous Fusarium fungi and triple parasitic wasp biocontrol of the caterpillar larvae of moth pests like fall armyworm (Spodoptera frugiperda).
Not everyone is a fan of turfgrass lawns, and before the modern chemical era lawns were more like fragrant flowery meadows. “Agricultural experts and agribusiness are bound by the idea that even land that has lost its natural vitality can still produce crops with the addition of petroleum energy, agricultural chemicals, and water…considering this form of agriculture to be advanced,” wrote Japanese agriculturist and philosopher Masanobu Fukuoka in the book, Sowing Seeds in the Desert (edited by Larry Korn).
“When I suggested that it would be a good idea to plant fruit trees to line the streets in towns and cities and to grow vegetables instead of lawns and annual flowers, so that when the townspeople were taking a walk, they could pick and eat the fruit from the roadside, people were surprisingly enthusiastic,” said Fukuoka. “When I suggested that it would be good to scatter the seeds of clover and daikon on the existing lawns so that in two or three years the clover would overcome the lawn and the daikon would take root amid the ground cover, interestingly, it was the Asian people and Asian-Americans who said they would try it right away. Most Americans would just laugh and agree with the theory, but they were cautious about putting it into practice. The reason, I believe, is that it would challenge their adherence to ‘lawn’ culture. If they cannot overcome this prejudice, there will be a limit to the growth of family gardens in the United States.”
“It seems that the main goal in the life of the average American is to save money, live in the country in a big house surrounded by large trees, and enjoy a carefully manicured lawn,” wrote Fukuoka. “It would be a further source of pride to raise a few horses. Everywhere I went I preached the abolition of lawn culture, saying that it was an imitation green created for human beings at the expense of nature and was nothing more than a remnant of the arrogant aristocratic culture of Europe…Because residential lots are large in the United States, a family vegetable garden can provide for all the food needs of a typical family, if they are willing to do the work. In Japan, a residential lot about a quarter acre would be enough to allow near self-sufficiency and provide a healthy living environment, but I learned—to my envy—that in many suburban and rural areas of the United States, people are not allowed to build houses on small lots.”
On closer inspection, modern American lawns are more often a biodiverse mixture of turfgrass and flowering plants like clover and dandelions. Kentucky bluegrass lawns may be 30% white clover, which favors native pollinators like bumblebees. Clover and dandelion flowers attract honey bees, bumble bees, parasitic wasps that kill pests, hover flies (syrphids) that eat aphids, and carnivorous rove and ground beetles eating snails, slugs, caterpillars and other pests. Nonetheless, tons of herbicides go onto USA lawns to eradicate clover and dandelions as weeds, often as part of fertilizer and insecticide mixtures.
Turf biodiversity is all well and good, but only as long as the clover and dandelion flower nectar is pure and uncontaminated by pesticide cocktails. Lawns laden with clover and dandelion flowers provide bees and beneficial insects with “a big gulp of nectar,” the University of Kentucky’s Jonathan Larson told the ESA annual meeting in Knoxville, Tennessee. When those “big gulps of nectar” are laced with certain neonicotinoid pesticides, the effects can ripple through the ecological food chain.
When turfgrass pesticide labels say, ‘Don’t treat flower heads,’ “Follow the label to the letter of the law” to avoid poisoning pollinators, said Larson. Or get rid of the flowering plants in the lawn by mowing the turf before spraying. Or delay pesticide sprays until after clovers, dandelions and other lawn flowers have finished flowering. Clover control in lawns using herbicides is difficult, and usually not feasible, Larson told the ESA. Hence, mowing is the preferred strategy for removing flowering lawn weeds before spraying pesticides.
In enclosure experiments with tents confining bees in the turf, mowing the turf before pesticide treatment mitigated the problem, resulting in more bees and more honey. In 2012, bees were tented on clothianidin-treated turf for 6 days and then moved for 6 weeks to a Lexington, Kentucky, horse ranch with unsprayed turf. Clothianidin reduced the rate of bumble bee weight gain, but at the end of 6 weeks the bees were starting to catch-up. But overall, the 6-day pesticide exposure still resulted in reduced bumble bee weight gain, less foraging and reduced queen and hive reproduction several weeks later. Chlorantraniliprole, which has a different mode of action (muscular), did not produce these adverse effects. Larson also told the ESA that clothianidin, a widely used neonicotinoid turf pesticide, also reduces decomposers (detritivores) like soil-dwelling earthworms and springtails more than chlorantraniliprole.
Besides supporting more soil life, more biocontrol organisms, and healthier crops of pollinating bees, you get a healthier turfgrass lawn if you do not need pesticides and do not have to mow so often. “Mowing height is an easily manipulated cultural practice that can have an impact on ecological conditions,” Samantha Marksbury from the University of Kentucky, Lexington, told the ESA. “Taller grass usually supports a more diverse ecosystem and increases natural enemies. Increasing cutting height stimulated deeper roots, yielding a healthier turf with less need for insecticide. Higher mowing height decreases need for irrigation and the canopy prevents water loss.”
Taller turf (raised mowing height) also tends to be more robust and more tolerant of white grubs. Nevertheless, about 75% of turf is lush residential monocultures (mostly one grass species) that is heavily fertilized, dosed with chemical herbicides and frequently mowed, Emily Dobbs of the University of Kentucky, Lexington, told the ESA. However, the ecology of grass cutting or mowing gets quite complex and has seasonal variations. In May, turf with a low mowing height (2.5 inches; 6.4 cm) was hotter, drier, and had the most predatory ground beetles, rove beetles and spiders. Later in the season and Sept/Oct, turf with a higher mowing height (4 inches; 10.2 cm) was cooler, wetter, and had the most predators.
Historically, in the Middle Ages in England, going back many centuries (even before Chaucer) before the age of chemical farming and gardening, lawns were “flowery meads” with roses, violets, periwinkles, primroses, daisies, gillyflowers and other colorful, fragrant flowers interplanted right into the turf. The idea of planting a lawn with one species of grass made no sense, though a camomile lawn or plot came into being for infirmary gardens in England after 1265, as this medicinal aromatic plant helped other plants growing nearby in poor soils and grew faster the more it was trodden.
“There were no flower-beds of the sort familiar to us,” wrote Teresa McLean in her 1981 book, Medieval English Gardens. “The simplest type of flower garden was the flowery mead, wherein low-growing flowers were planted in turf lawns, sometimes walled, sometimes left open, to make a beautiful domestic meadow. The flowery mead was the locus amoenus of God’s beautiful world.”
“Trees were often planted in raised turf mounds, surrounded by wattle fences, which doubled as seats,” wrote McLean. “Medieval lawns, unlike modern ones, were luxuriously long, and full of flowers and herbs; they were fragrant carpets to be walked, danced, sat and lain upon. What modern lawn could find a poet to write about it as Chaucer wrote about the one in the Legend of Good Women?
Upon the small, soft, sweet grass,
That was with flowers sweet embroidered all,
Of such sweetness, and such odour overall…”
A TRUISM IN TRAVEL is that on your first trip to a destination you learn what you should have done or gone to see. Sometimes you get back to do or see it, and sometimes you don’t. It is even more difficult, for scientific research as well as travel, to be there to witness rare, occasional or brief seasonal events in the life of a plant, animal or region. For example, I was in New Zealand the wrong season, and missed their famous glowworm (firefly) caves. Too much is happening and the world is too big to see or do everything; and some things are out of our vision, anyway; being too big or too small, too distant, or in the ultraviolet, infrared or some other electromagnetic frequency beyond our immediate sensory perception.
Viewing firefly (aka glowworm; lightning bug, firefly beetle, hotaru) photonic light displays at their rhythmically flashing best means being in the right place at the right time. Many of the world’s 2,000 known fireflies species lack the night fire, and are rather anonymous. Some glow as eggs and larvae (presumably to ward off predators), and as adults (advertising for mates). But most of the year, even the best flashers remain hidden (often as eggs, larvae or pupae) in the soil. More rarely, some esteemed Asian species have underwater larval life stages living in rivers, streams, wetlands and rice paddies and providing biocontrol of freshwater snails. The genji-botaru and heike-botaru fireflies (hotaru), celebrated since the 8th century in Japanese poetry (e.g. Man’yoshu) as early-summer “little lights darting about in the night,” are also icons of water purity.
Enchanting traveler’s tales involve the synchronous rhythmic flashing of many thousands, perhaps millions, of fireflies as far as the eye can see across the landscape. “Over the past four hundred years many anecdotal accounts of synchronous flashing of myriads of fireflies in trees in Southeast Asia have been scattered through travel books,” wrote pioneering firefly scientist, John Buck, who got started wondering about fireflies as a kid and advanced his studies working with his wife, Elisabeth, during summer vacations from his main work at the National Institutes of Health. “Pride of place in antiquity passes from Kaempfer’s (1727 Dutch physician’s book: The History of Japan (With a Description of the Kingdom of Siam)) description of synchronized flashing at the classic locality, the banks of the Chao Phraya (Meinam) River in Thailand, to Hakluyt’s (1589 book: A Selection of the Principal Voyages, Traffiques and Discoveries of the English Nation) account of what was probably the same phenomenon, as seen by Sir Francis Drake’s 1577 expedition: ‘a certaine little Island to the Southwards of Celebes…Among these trees, night by night, through the whole land, did shew themselves an infinite swarme of fiery worms flying in the ayre…make such a shew of light, as if every twigge or tree had been a burning candle.’”
Synchronized firefly flashing was late being recognized in the Americas. “Early in this century sightings of synchrony among flying fireflies in American meadows began to appear,” wrote John Buck in 1988. “No reasonable explanation of the behavior was offered: in fact a strong aura of incredulity or even mysticism pervaded the subject.” Indeed, when John Buck started studying fireflies in earnest in the 1930s: “The fast film, laboratory oscilloscope and image-intensifier that would eventually confirm and dissect synchrony were, like the jet airplane…still in the future…Today the phenomena has been photographed, charted, and videotaped…”
“The modern study of synchrony in fireflies dates from 1968, when John and Elisabeth Buck used cine photography and photometry to demonstrate that a certain number of Southeast Asian firefly species flash in rhythmic synchrony,” wrote Jonathan Copeland and Andrew Moiseff, who “used videography, photometry, computer-shaped LED flash, and flash entrainment experiments” in their own studies of flash rhythms in the synchronous firefly, Photinus carolinus, a popular tourist attraction in Tennessee’s Great Smoky Mountains National Park.
When the Entomological Society of America (ESA) met for its annual meeting in Knoxville, TN, in November (2012), the synchronous fireflies famous for what locals call “The Light Show” were slumbering about 50 miles away in the former logging town of Elkmont, which was swallowed up (residents sent packing) into Great Smoky Mountains National Park. “Huge numbers of male fireflies flash synchronously, dazzling the human spectators and drawing female P. carolinus for the purpose of mating,” wrote Lynn Faust of the Great Smoky Mountains Conservation Association, a former Elkmont resident, who along with local volunteers have collected 20 years of firefly data; aided by Paul Weston (Charles Sturt University, New South Wales, Australia) and other scientists.
“The display lasts only several days to slightly over a week, which means that the ability to predict its occurrence is of critical importance to the National Park Service, which organizes shuttle buses to ferry visitors from parking areas to the ecologically sensitive areas where the fireflies put on their display,” Faust and Weston told the ESA annual meeting. For the 10-day peak Light Show display, there have been up to 26,000 tourists. “Predicting the timing of this natural phenomenon is of equal importance to the researchers and naturalists who study its annual occurrence.”
In his Newbery Medal winning book (1989), Joyful Noise: Poems for Two Voices, poet and children’s book author, Paul Fleischman, calls fireflies: “…glowing insect calligraphers practicing penmanship…Six-legged scribblers of vanishing messages, fleeting graffiti…Fine artists in flight adding dabs of light, Signing the June nights as if they were paintings…” A description hard to top, even with the many fine firefly night light paintings from light shows around the world displayed on photographs on the Internet and in YouTube videos.
“The synchronous firefly Photinus carolinus (Green) of the moist cove hardwood forests of the Great Smoky Mountains National Park attracts much public attention during its spectacular month-long mating display known as The Light Show,” writes Lynn Faust in the Florida Entomologist. Besides the human tourist hordes, predatory biocontrol species also seem attracted to The Light Show: “Orb-weaving spiders (Araneidae) prey on P. carolinus. Late at night, after all courtship flashing had ceased, often the only lights visible were the rhythmic distress flashes or the steady glow of fireflies caught in webs. In addition, harvestmen (Phalangiidae) often were seen carrying glowing pupae, adult fireflies, or only the still glowing firefly lantern…local Photuris fireflies readily eat captive P. carolinus and regularly fly and signal within the dense display areas of male P. carolinus… Phorid flies (Apocephalus antennatus Malloch) parasitize Photinus fireflies by ovipositing eggs within the firefly’s body…” So, with the risk of being eaten by predators and becoming part of the greater ecological food chain during the short performance season, the life of an adult firefly Light Show performer must be as tough as it is brief.
Over the past two decades, lifelong firefly-enthusiast Faust and the Great Smoky Mountains Conservation Association volunteers collected data on “four landmark phenological events,” namely: 1) male emergence (date on which first flashing male fireflies are observed); 2) “good” display (date synchronized flashing by males is seen over wide areas; not just isolated patches); 3) female emergence (date of first female flashing in response to males; doublet flashes in leaf litter or low vegetation); and 4) peak display (final night of maximum male flashing displays; determined in retrospect, usually after a sudden fading out of The Light Show).
“A degree-day model based on a base temperature of 50 F (10 C) and a seasonal starting date of March 1 has resulted in remarkably accurate predictions of four landmark phenological events for Photinus carolinus,” Faust and Weston told the ESA. “This predictive ability has proven very helpful for timing research visits to field sites, and will be a valuable tool for the National Park Service when scheduling visits of thousands of visitors to the Smokies Mountain National Park to witness the Light Show.” The better the prediction of when “The Light Show” will occur, the more likely researchers, tourists and travelers will come away satisfied; versus feeling like they missed out.
“The Light Show is the name given by locals in the Smoky Mountains to the annual synchronous display of male P. Carolinus,” Faust and Weston told the ESA. “The males produce a string of about 6 flashes over 3-4 seconds, then remain dark for 6-15 seconds. Remarkably, these fireflies synchronize their flashes and dark intervals with those of their neighbors, which leads to visually striking displays stretching as far as the eye can see into the wooded hillsides and glens of the Smoky Mountains. The display can last for 2 hours or more on peak nights.”
The mathematics or calculations behind degree days (aka day-degrees, growing degree days, heat sums, thermal units, threshold temperatures) can be a bit tedious, but degree days are basically just a way of calculating the impact of temperature on a life process (or physiology). Degree days are used in botany, horticulture and agriculture to predict a range of phenomena, including flowering times, as higher temperatures mean plant enzymes are more active. Insects are also temperature-dependent creatures. Thus, degree-day models work to predict firefly adult emergence and light show times. Similarly, degree-day models can help time pest control actions by predicting the egg hatch of the codling moth, the proverbial worm inside the apple.
Raymond Bonhomme nicely sums up the agriculture origins of the degree-day concept: “The ‘degree-day’ unit stems mainly from the relationship between development rate and temperature. It was Re´aumur (1735) who first laid the basis of this notion: ‘The same grains are harvested in very different climates; it would be interesting to compare the sums of heat degrees over the months during which wheat does most of its growing and reaches complete maturity in hot countries, like Spain or Africa … in temperate countries, like France … and in the colder countries of the North,’ (original text in Old French: Durand, 1969). Even if the exact vocabulary was not correct (what is a sum of heat degrees?), the concept of a relationship between the development rate of crops (here the sowing to maturity period) and temperature was born. Hundreds of works have set about using, proving, or even disproving this idea…”
Degree days are only a warm-up exercise for mathematicians and computer scientists studying the synchronous rhythms and periodicities of fireflies. Indeed, synchronous flashing in fireflies may have similarities to other physiological events, like the human heartbeat (cellular coordination) or the schooling and swarming behaviors of fish and birds. No doubt some envision coordinating the actions of armies of drones or robots, though the Ant Colony Optimization (ACO) or Particle Swarm Optimization (PSO) algorithms might be better for that. Rather than being the dark warlike side of the light show, this work could also do great good in helping fight diseases involving coordination at the cellular or other levels, aiding theatrical productions or designing swarms of robotic devices for hazardous situations like fighting toxic disasters.
“Rhythmic communal synchronization occurs in body movements and sound production of a few insects and other arthropods,” wrote John Buck in 1988. “It is also typical of many human activities—e.g., dancing, the spontaneous rhythmic applause clapping by Russian opera, ballet and circus audiences and, notably, music. Even conducted orchestral music involves a large element of mutual cueing between performers.”
Hearing about the Firefly Algorithm, the mental lights flashed that it was perhaps created by Rufus T. Firefly, President of the bankrupt country of Freedonia, played by Groucho Marx in the 1933 USA movie, Duck Soup. But the Firefly Algorithm (FA) and the Improved Firefly Algorithm (IFA) are being studied by computer scientists and mathematicians trying to solve difficult optimization problems like “the famous economic emissions load dispatch optimization problem,” which is “one of the key problems in power system operation and planning in which a direct solution cannot be found.”
The Firefly Algorithm, developed in 2007 by Cambridge University’s Xin-She Yang, is simply a set of rules or problem-solving steps, in this case inspired by nature and programmed for computers based in part on the details of flashing firefly lights, an insect social or swarm activity. “Although the real purpose and the details of this complex biochemical process of producing this flashing light is still a debating issue in the scientific community, many researchers believe that it helps fireflies for finding mates, protecting themselves from their predators and attracting their potential prey, said Theofanis Apostolopoulos and Aristidis Vlachos of the University of Piraeus (Greece) in the International Journal of Combinatorics. “In the firefly algorithm, the objective function of a given optimization problem is associated with this flashing light or light intensity which helps the swarm of fireflies to move to brighter and more attractive locations in order to obtain efficient optimal solutions.”
Besides energy conservation algorithms for heating, ventilation and cooling (HVAC) systems, understanding firefly light production is a path to more energy-efficient household and industrial lighting. “The firefly produces its narrow-spectrum 560 nanometer light just like a chemical laser, but with even greater control,” writes Extreme Tech columnist, John Hewitt. “Understanding firefly scales as tiny prisms that change the way light impinges on an interface and creates new sharp-edged channels through which light can diffuse lets us make LEDs more efficient.” Indeed, mimicking firefly light transmission can boost light production from GaN (Gallium Nitride) LEDs by 55%.
As the Ohio State Parks web site notes in their succinct discussion of firefly bioluminescence chemicals, luciferin and luciferase: “Scientists are still not sure exactly how fireflies control their lights, but they have found many important uses for the chemicals luciferin and luciferase. Since living cells have ATP and oxygen, researchers can add luciferin and luciferase to detect harmful bacteria in food, milk or water. The two chemicals are also used for special electronic detectors used in spacecraft to look for earth-life forms in outer space! Luciferin and luciferase are also being used in research on human diseases such as cancer, multiple sclerosis, cystic fibrosis, and heart disease. Firefly technology has also been used to produce safer, cold light for flashlights, flares and holiday lights.”
This is only the tip of the iceberg in innovation from studying fireflies. Just something to think about next time you are out watching fireflies, whether in your backyard, the Great Smoky Mountains or anywhere else on the planet.
CATERPILLAR FUNGI ARE not everybody’s finger food, though their beautifully-sculpted medicinal mushrooms are rich in fiber, amino acids, minerals and vitamins. The caterpillar fungus of commerce, Cordyceps sinensis, grows high in the Himalayan Mountains in the larvae (caterpillars) of equally high-altitude Asian ghost moths (genus Hepialus). An ancient medicine or tonic, caterpillar fungus is in reality part insect (mummified caterpillar) and part fungus; and perhaps a conundrum for vegetarians, who might have to take a pass on its medical benefits because of its animal kingdom (insect) component.
“Cordyceps is an abundant resource of useful natural products with various biological activity, and it has been used extensively as a tonic and health supplement for subhealth patients, especially seniors, in China and other Asian countries,” write Kai Yue and colleagues at Sichuan Agricultural University in an article pre-published online in October 2012 in the Royal Pharmaceutical Society’s Journal of Pharmacy and Pharmacology.
For perhaps thousands of years (at least several hundred) in China and other Asian countries, “Cordyceps sinensis (Caterpillar fungus) has been used as a tonic for longevity, endurance, and vitality,” write Chinese Academy of Sciences researchers Zhenquan Liu et al. in an Open Access journal, Behavioral and Brain Functions. “Many studies have shown that Cordyceps sinensis modulates immune responses, inhibits tumor cell proliferation, enhances hepatic function, regulates insulin sensitivity” and modulates steroid production.
“Although Cordyceps sinensis is extensively used in Chinese medicine, it lacks scientific grounds for its efficacy,” write Liu et al. In other words, it has worked like magic for centuries; providing practical benefits, though the exact mechanisms of how it works are unknown or speculative. The Chinese researchers argue that even proponents of modern medicine objecting to traditional natural or folkloric medical treatments could benefit from studying the caterpillar fungus. Their argument is that the research results from studying the mechanisms of how the caterpillar fungus works to heal or prevent disease could also be used to develop more conventional medical or drug treatments.
Caterpillar fungus could be particularly useful for certain brain strokes, where modern medicine lacks effective drugs and treatments. ”The lack of effective and widely applicable pharmacological treatments for ischemic stroke patients may explain a growing interest in traditional medicines,” wrote Liu et al. An example is “self-medication or preventive medicine” to prevent cerebral ischemia. In this type of stroke, brain oxygen levels are too low; which can trigger a cascade of biological events leading to brain damage and death. Caterpillar fungus prevents or protects against this type of brain stroke (“ischemia-induced brain infarction”), presumably by inducing or modulating production of a steroid, 17beta-estradiol.
Cordyceps sinensis mushrooms growing out of golden caterpillar bodies are sometimes artfully and decoratively displayed in high-end Chinese herbal shops. Caterpillar fungus achieved some notoriety when it was revealed to be a dietary supplement for Chinese athletes bringing home gold and silver medals at the 2008 Beijing Olympics.
“In China, this fungus is usually called ‘Dong Chong Xia Cao,’ which means ‘Worm in winter and grass in summer,’” write Kai Yue and colleagues at Sichuan Agricultural University. “This insect parasitizing fungus lives primarily on the head of the larva of one particular species of moth, Hepialus armoricanus Oberthur (Lepidoptera), but is occasionally found growing on other moth species. Cordyceps was first introduced to Western society during the 17th century. In 1878 Saccardo, an Italian scholar, named Cordyceps derived from China officially as Cordyceps sinensis (Berk.) Sacc., and this nomenclature has been adopted up to the present day.”
At a Nepal Overseas Entomologists members symposium at the Entomological Society of America (ESA) annual meeting in Nov. 2012, at the Convention Center in Knoxville, Tennessee, Bhishma Subedi of the Asia Network for Sustainable Agriculture and Bioresources (ANSAB) screened a 20-30 minute documentary film as part of a talk titled, “Cordyceps sinensis a natural viagara(sic) from the mountains of Nepal.” Even the other Nepali entomologists in attendance learned something new, as the caterpillar fungus is found only in remote Himalayan Mountain locales; and it is not common knowledge, even in Nepal.
Known in Nepal by its Tibetan name, yarsagumba, caterpillar fungus is well-hidden; blending like a camouflaged black joss stick into black soils and grasses on slightly north-facing (5-10 degrees) Himalayan slopes 3,200 to 4,500 meters (10,500 to 14,800 ft) high. Yarsagumba lands are several days trek from anyplace where people normally live, and the ground is covered in snow 6 months of the year. But this is where temporary high-mountain camps must be set up for hunting the difficult-to-find caterpillar fungus.
Searching for the camouflaged black and debris-covered yarsagumba means crawling on hands and knees or bending over among short grasses and melted snow. Men search for yarsagumba and other medicinal herbs in the vicinity, while women stay behind and maintain the base camps. A certain Buddhist purity is maintained in yarsagumba lands; there is no alcohol, no tobacco and no shouting, loud voices or arguing. People pray, and the first yarsagumba found is offered to the Gods.
The beauty of the mountains belie the harshness of the climate and the difficulty of the life in search of yarsagumba; it’s a tough way to earn money in these remote mountains where economic opportunities are few. Storms can come at any time, and it is easy to fall down a steep cliff when climbing in the snow. A fall near a cliff edge can mean loss of limbs and frequently death. There are no second chances, no safety nets to catch you up here. Medical treatment is do-it-yourself, by necessity. Conventional medicine and doctors are many days distant. Widows are commonplace at all ages; and many subsistence families in Nepal have lost husbands, fathers, brothers and sons during the search for yarsagumba and medicinal herbs that may help others prevail against brain strokes and other maladies.
It takes seven cleanings with a toothbrush to remove all the debris and black soil, and make the black yarsagumba look like a proper insect, namely a golden caterpillar. The going price from the middlemen is 80,000 rupees per kilo; with 3,500 to 4,000 pieces of clean golden caterpillars per kilo. It takes five people a month to find a kilo. People are doing well to come out of the season with 60,000 rupees, before the expenses of the trek and weeks or months of camp costs. Recently, the Nepal government imposed a 20,000 rupee per kilo tax or royalty on the trade.
After being steamed and packaged, most of the yarsagumba eventually is exported and finds its way to the Chinese market. The yarsagumba trade is estimated at 2 tons annually. But in Nepal, since the government-imposed 20,000 rupee/kilo royalty or tax went into effect, it was like the yarsagumba harvest had become illegal for Nepal’s subsistence mountain people. Royalties were paid on only 3 kilos in a recent year. Perhaps there is a free market and tax lesson in all this. Or perhaps it is just part of the great wheel of life.
Many bird species provide biocontrol by eating a wide range of insect pests, and are worth encouraging for controlling flies, mosquitoes, locusts, caterpillars, ticks, rodents and other pests around homes, forests, farms and gardens. Other bird species are considered pestiferous when feeding on our food plants, and can be repelled in various ways, including by loud noises, eyespot balloons, reflecting tape, scarecrows and scare devices, sensor networks and dogs.
Among the beneficial birds when they are not causing damage to utility poles or annoying people with their racket are woodpeckers. Personally, I like hearing woodpeckers working urban and forest trees, and was heartened to learn from Michigan State University’s Andrew Tluczek’s presentation to the Entomological Society of America (ESA) annual meeting that: “Woodpecker predation has caused up to 90% mortality of emerald ash borer (Agrilus planipennis) larvae in some sites.”
A 2006 tick control article in BioScience magazine devoted considerable discussion to birds for tick biocontrol. In Africa, birds known as oxpeckers (Buphagus spp.) provide biocontrol of ticks on mammals by consuming hundreds of adult ticks or thousands of nymphal ticks per day. Free-ranging guinea fowl experimentally tested around New York (USA) lawns reduced adult blacklegged tick numbers; but unfortunately the smaller nymph stage blacklegged ticks transmitting Lyme disease apparently were missed and not stopped very well.
The list of bird benefits for biocontrol, like barn owls for rodent biocontrol in Israel, Palestine, Malaysia and elsewhere could go on and on.
“Bird damage situations throughout the world are similar, involving many of the same crops and genera of birds,” wrote John W. De Grazio a few decades ago in the <em>Proceedings of the 8th Vertebrate Pest Conference. Seed-eating red-winged blackbirds, ring-necked pheasants, sparrows, crows, doves, parrots, munias, queleas, weavers and waterfowl are sometimes pests of corn, rice, wheat, sorghum, sunflowers, almonds, pecans, peanuts, etc. Starlings, sparrows, finches, grackles, robins, parakeets, etc. consume grapes, blueberries, and other fruit in yards, vineyards and orchards.
Dogs are used in pest control for sniffing out termites and bed bugs, and the natural proclivity of some dog breeds to chase birds can be harnessed to keep birds from destroying fruit in orchards and vineyards. In researching a grant proposal to travel to and write about Japan, which I failed miserably to qualify for, my Internet research for the proposal took me to the Japanese Journal of Farm Work Research. Being one of a select 4% of the USA population to have worked in agriculture, the journal title intrigued me enough to browse through several years of tables of contents, where I came across an intriguing article title: “Protection of Citrus From Bird Damage by a Dog.”
Not reading Japanese, I had to rely on the visual diagrams and English summary by researchers Hiromichi Ichinokiyama and Masami Takeuchi at the Kinan Fruits Tree Laboratory and Mie Prefectural Science and Technology Promotion Center:
“Effectiveness of a dog (Canus lupus familiaris) for protecting citrus fruits from bird damage was investigated using a citrus orchard (5.8 a in area) in the harvest season. In Experiment 1, a Border collie shepherd (male) was tied to a wire extended along one side of the square orchard to allow him to run along the inner side of the orchard. This watchdog system was effective in reducing fruit damage by birds (mainly brown-eared bulbul) only in the citrus tree row nearest to the dog runway.”
However, the researchers had better success letting the dog run free in the orchard:
“In Experiment 2, the orchard was enclosed with a tall chain-link fence and the same dog was allowed to move freely in the orchard. In this case, he persevered in chasing birds until they flew away from the orchard. This watchdog system effectively reduced bird damage to citrus fruits all over the orchard, resulting in an increase in crop yield…Further study is needed on the optimum number of dogs released per unit orchard area and the effectiveness of the watchdog system in case when this bird control system is spread to all orchards in the citrus-growing area.”
Like Richard Feynman’s Nontoxic Ant Ferry, dogs chasing birds away from trees laden with fruit or nuts is more a proof-of-concept awaiting further development than a fully developed technology you can order on the Internet.
Thank you to the organizations and people who created and are advancing the Internet, as even finding this sort of information would have been nearly impossible a few decades ago. Amazing how this high-tech infrastructure can advance low-tech solutions like the old-fashioned four-legged, tail-wagging dog as a bird-chaser in service of better fruit harvests.
CARBON DIOXIDE GAS, an essential nutrient for photosynthesis and the human and animal food chain consuming green plants, can also play a key role in bed bug control. As an attractant, carbon dioxide (CO2) is useful for monitoring and trapping bed bugs and other vampire-like blood-suckers attracted to the gas, including ticks, mosquitoes, and assorted biting flies. Carbon dioxide gas, which has been used to fumigate everything from stored grain and food products to freight containers, museum collections, and hotel and motel rooms, can also be used to fumigate clothing, furnishings, books, electronics, and other bed bug-infested items.
Carbon, carbon dioxide, and the carbon cycle are integral to our very existence on planet Earth. “The carbon of the Earth comes in several forms,” writes University of Cambridge chemist John Emsley in his fascinating Oxford University Press book, Nature’s Building Blocks (An A-Z Guide to the Elements). “Most of what we eat –carbohydrates, fats, proteins and fibre – is made up of compounds of carbon…most ingested carbon compounds are oxidized to release the energy they contain, and then we breathe out the carbon as carbon dioxide. This joins the other carbon dioxide in the atmosphere, from where it will again be extracted by plants and become part of the carbon cycle of nature…The cycle rules the tempo of life on Earth and turns over 200 billion tonnes of carbon each year…In this way carbon is passed up the various food chains, with each recipient releasing some as carbon dioxide, until most carbon is back where it started.”
Does this mean that using carbon dioxide for bed bug control is environmentally acceptable, since it is kind of a “miracle of life” gas behind photosynthesis and plant life? Or is carbon dioxide really more the evil greenhouse or global-warming gas causing global climatic havoc and deserving of punishment via carbon taxes and elimination from the atmosphere via geological carbon sequestration (storage) schemes? Perhaps we should offset carbon dioxide releases for bed bug pest control with offsetting carbon dioxide injections into greenhouses, where elevated CO2 levels increase yields of greenhouse roses, tomatoes, cucumbers, peppers and other crops.
“Carbon is probably the most important element from an environmental point of view,” writes Emsley in Nature’s Building Blocks. “The Earth’s early atmosphere may have contained a lot of carbon dioxide and methane, but once life evolved that began to change. Today, there is very little of these gases and a lot of oxygen instead, thanks chiefly to the action of plants which convert carbon dioxide and water into carbohydrate and oxygen by photosynthesis. The Earth’s atmosphere contains an ever-increasing concentration of carbon dioxide and carbon monoxide, from fossil fuel burning, and of methane, from paddy fields and cows. Human contributions to these sources are still minor compared with natural sources: most carbon dioxide comes from plants, microbes and animals, while methane is given off by swamps, marshes and termite mounds.”
Obviously best to avoid bed bug infestations, and not have to think about remedies like carbon dioxide trapping or fumigations. Italian chemist Primo Levi makes the most persuasive literary argument: “Carbon dioxide, that is, the aerial form of carbon…this gas which constitutes the raw material of life, the permanent store upon which all that grows draws, and the ultimate destiny of all flesh, is not one of the principal components of air but rather a ridiculous remnant, an ‘impurity,’ thirty times less abundant than argon, which nobody even notices. The air contains 0.03 percent; if Italy was air, the only Italians fit to build life would be, for example, the 15,000 inhabitants of Milazzo in the province of Messina. This, on the human scale, is ironic acrobatics, a juggler’s trick, an incomprehensible display of omnipotence-arrogance, since from this ever renewed impurity of the air we come, we animals and we plants, and we the human species, with our four billion discordant opinions, our millenniums of history…”
Bed bugs concern themselves little with environmental correctness, and just tune into characteristics like the heat and carbon dioxide released by metabolizing warm-blooded meal hosts like humans, poultry, rodents, rabbits, etc. A flush from a CO2 cartridge is enough to flush bed bugs from their harborages or hiding places onto a bed in search of a meal. But more naturally, bed bugs follow CO2 gradients to locate live hosts for their blood meals.
“Carbon dioxide has been shown by several researchers to be the most effective attractant for bed bugs,” University of Florida-Gainesville entomologist Philip Koehler told a recent Entomological Society of America (ESA) annual meeting. Humans produce about 700 mg (0.02 oz) of CO2 per minute. “Thus, detectors with very slow CO2 releases cannot compete with human hosts,” said Koehler. “A rapid CO2 release is a better mimic to the human breathing pattern. Detectors with fast CO2 release captured about 4x more bed bugs than detectors with slow release.”
Trapping or monitoring bed bugs with CO2 is complicated by the fact that at different times in the life cycle bed bugs seek out hosts (releasing CO2) for blood meals when hungry; and then when well-fed, instead of CO2 bed bugs seek shelter in groups or cracks and crevices. So although CO2 is the better lure for hungry bed bugs, bed bugs that have fed have different needs and respond to different lures.
A commercial product, FMC’s Verifi(TM) trap, is a dual-action detector combining “fast CO2 generation with liquid kairomone and pheromone lures to attract both host-seeking bed bugs and aggregation-seeking bed bugs,” Koehler told the ESA. Carbon dioxide and the kairomone lure blood-seeking bed bugs into a pitfall part of the trap from which there is no escape. A pheromone lures harborage- or aggregation-seeking bed bugs seeking shelter in cracks and crevices into another part of the trap.
“An inexpensive detector that can be left in place and routinely serviced is needed to aid pest management professionals,” Ohio State University’s Susan Jones told the ESA. “Rutger’s do-it-yourself dry ice (frozen CO2) traps are a cheap and effective method for overnight surveys of potentially infested habitations.” An experiment in a 13-story high-rise apartment building in Columbus, Ohio compared (see You Tube video) 3 Verifi(TM) bed bug detectors per room with 1 CO2-generating dry ice trap per room and canine (dog) detection teams (2 dogs/room; same handler).
Verifi(TM) traps detected bed bugs in 11 of 17 infested rooms in the first 24 hours; and in 14 of 17 infested rooms within a week. Dry ice traps had similar efficacy. Dogs detected bed bugs in 19 rooms, including 3 rooms where neither visual inspections nor dry ice or Verifi(TM) traps detected anything. But the dogs were also not perfect, as each dog also missed 1 room rated positive for bed bugs. So the quest to capture bed bugs with carbon dioxide and other lures goes on.
Human ingenuity seems almost unlimited when it comes to traps. Carbon dioxide, heat and other attractants are all being tested with traps as varied as Susan McKnight Inc.’s Climbup bed bug trap and pitfall traps made from inverted dog bowls painted black on the outside. Rutgers’ Narinderpal Singh tested CO2, heat, and lures such as nonanol, octanol, 1-octen-3-ol, coriander, and spearmint with inverted dog bowl pitfall traps. CO2 had an additive effect with multiple-component lures in inverted dog bowl traps, and may be developed into an inexpensive monitoring system for detecting low levels of bed bugs. Trials with baited traps are continuing.
Both carbon dioxide and ozone show fumigant potential against bed bugs. Purdue University’s Kurt Saltzmann told the ESA of “Two devices capable of delivering ozone to laboratory fumigation chambers.” One device delivered a short exposure to high ozone levels, and the other long exposure to low ozone levels. “Preliminary experiments showed that adult male bed bugs were susceptible to relatively short periods of ozone exposure when high concentrations of ozone were used,” said Saltzmann. “100% mortality was achieved when bed bugs were exposed to 1800 ppm ozone for 150 minutes.” Low ozone fumigation is also being tested with 1-2% hydrogen peroxide for up to 72 hours.
Carbon dioxide (CO2) is used by libraries, museums, and others as an insect-killing fumigant. Indeed, dry ice (frozen CO2) to release CO2 gas is cheaper than washing and drying fabrics to kill bed bugs, Rutgers University’s Changlu Wang told the ESA. At an 80% concentration, CO2 kills all bed bug eggs in 24 hours (eggs are the toughest bed bug life stage to kill). A 50% CO2 concentration for 8 hours is sufficient to kill bed bug nymphs (immatures) and adults.
Wang’s CO2 fumigations involved filling Husky garbage bags 90% full of items such as mattress covers and fabrics, leaving little room for air. Then the bags were sealed with dry ice inside for several hours. Books, electronics, toys and other items damaged by heat treatments might benefit from the low temperatures created by dry ice treatments. However, for safety reasons Wang recommends wearing gloves and turning on fans for ventilation when opening many bags filled with carbon dioxide gas (fumigant).