Moth-Eye Reflections

“ANTI-REFLECTION MOTH-EYE ARRAYS are now widely applied in panels of instruments, like cellphones and in window panes,” wrote Doekele G. Stavenga of the Department of Neurobiophysics at the University of Groningen (The Netherlands) in Functional Surfaces in Biology -Little Structures With Big Effects, Volume 1. The editor, Stanislav Gorb of the University of Kiel (Germany), thanked senior publishing editor Zuzana Bernhart (Plant Pathology and Entomology; Springer, Holland) for her “belief in this topic and her personal help.” Bernhart said that a big dose of the inspiration for the two book volumes came from what have become regular symposia on insect-inspired innovations at the Entomological Society of America (ESA) annnual meetings.

At nanotechnology events, insects and entomology are acknowledged frequently as inspiration. For example, at the California NanoSystems Institute on UCLA’s campus, Tomohide Takami, a researcher visiting from the Division of Quantum Phases and Devices at Konkuk University (South Korea), said “we have fabricated a bio-mimetic probe called ‘nano-mosquito’…to explore nano-world.” In a prior lecture Xiaodong Chen visiting from Nanyang Technological University (Singapore) noted: 1) energy storage devices, lightweight aerospace materials, and self-assembly inspired by diatoms and honey bee honeycombs; 2) Singapore’s waterfront Esplanade Theatres on the Bay is an architectural shape perhaps inspired by fly eyes and tropical fruit (durian); 3) moth eyes that are anti-reflective (so enemies do not see the glint of their eyes) and provide better vision at night and in fogs inspire solar cells that harvest more light.

“Anti-reflective moth-eye arrays could produce up to 12% more energy than those employing single layer anti-reflective coatings,” via “a reduction of up to 70% of the light reflected from the surface,” said Stuart Boden and Darren Bagnall of the University of South Hampton (UK) in their poster display (“Bio-mimetic nanostructured surfaces for near zero reflection from sunrise to sunset”). Via electron beam lithography and dry etching (subwavelength): “We have fabricated a range of moth-eye arrays in silicon. Reflectance measurements confirm the low reflectivity of these arrays over the visible and near infra-red wavelengths, making them excellent candidates for reducing reflection on solar cells.”

“Insects have facetted, compound eyes, consisting of numerous anatomically identical units, the ommatidia,” wrote Doekele Stavenga and his colleagues in the Proceedings of the Royal Society B (22 March 2006. 273(1587):661-667), a journal whose roots date back over 200 years to London in 1800. Back in the 1960s, researchers discovered that the outer surfaces of moth eyes had “an array of cuticular protuberances termed corneal nipples” which reduce light reflection to 1%. Thus, moth night vision is improved by allowing 99% of light to enter moth eyes. Fewer reflections or less glint from the eyes makes moths harder for predators to detect. [Moth defenses against bat echo-location is another story, for another time]

“Moths thus realize a much higher light sensitivity than butterflies, allowing a nocturnal instead of diurnal (daylight) lifestyle,” wrote Stavenga et al. “A moth with large, glittering eyes will be quite conspicuous, and therefore its visibility is reduced by the eye reflectance decreasing… The insight that nipple arrays can strongly reduce surface reflectance has been widely technically applied, e.g. in window panes, cell phone displays and camera lenses.”

Moth-eye antireflection coatings (ARCs), “which are inspired by the grainy microstructures on the corneas of moths consisting of a non-close-packed hexagonal array of conical nipples, can suppress reflection over a broader range of wavelengths and wider angles of incidence than traditional multilayer dielectric ARCs,” wrote Chih-Hung Sun and other chemical engineering colleagues at the University of Florida, Gainesville, in an article titled “Large-scale assembly of periodic nanostructures with metastable square lattices.”

Moth-eye ARCs, reported Sun et al., “are widely utilized in eliminating the “ghost images” for flat-panel displays, increasing the transmittance for optical lenses, improving the out-coupling efficiency of semiconductor light emitting diodes, and enhancing the conversion efficiency of solar cells.”

“Since all biological structures are multifunctional, it makes them even more interesting,” wrote Stanislav Gorb in his introduction to the Springer book, Functional Surfaces in Biology. “Small surface structures at the micrometer and nanometer scales (i.e. very very small) are often vitally important for a particular function or a set of diverse functions…Because of the structural and chemical complexity of biological surfaces, exact working mechanisms have been clarified only for some systems.”

Some other possible innovations from the micro-world described in the Springer book: Protective slime coatings that protect seeds from rotting (e.g. pathogens) and stimulate or inhibit seed germination as needed. Water-repellent hairs have been “invented” by spiders. Water bugs can inspire waterproofing, anti-submersion fabrics, and surfaces promoting water runoff. Self-cleaning plant surfaces that cause water to form spheres and roll off are inspiration for water-repellent surfaces that might also trap air underwater for breathing. The plant world’s system of water transport pipes (xylem) can yield ideas for water transport systems. Feather microstructures could inspire aerodynamic innovations to complement lessons learned from insect flight.

We have barely scratched the surface of the ingenious natural world that we inhabit and share.

Asian Innovations in Insect Control

Innovations in Insect Control in Asia date back almost 2,000 years to when ancient Chinese farmers learned the art of biological insect control. China’s ancient orchardists annually introduced colonies of predatory ants to cultivated trees to control caterpillars and other pests of crops such as citrus. Ancient Chinese biocontrol practices included constructing bamboo bridges between trees, so predatory ants could easily wander from tree to tree foraging for pests.

Fast forward to the twenty-first century: Tea is arguably the second most widely consumed beverage, after water. Tea production occupies 2.7 million ha (6.7 million acres) in 34 countries, with 78% of production in Asia and 16% in Africa. Sustainable tea production practices emphasize displacing pesticides with cultural and biological control practices to control spider mites and other pests in tea plantations.

“The application of natural enemies in tea pest control aroused a large amount of investigations in the tea producing countries,” reported Yang Yajun and colleagues at the Tea Research Institute of Chinese Academy of Sciences at the 2005 International Symposium on Innovation in Tea Science and Sustainable Development in Tea Industry. “In South India, investigations showed the introduction of three species of entomophagous fungi in the control of tea spider mite (Oligonychus coffeae). In Japan, the use of pesticide-resistant predatory mite resulted in successful control…In Japan, one fungal preparation and one bacterial preparation were registered and used in control of tea diseases.” In China and Japan, viruses stop pesky leafrollers and loopers. Japan also has five fungal biocontrol products, one bacterial biocontrol preparation, and several kinds of parasitic and predatory natural enemy preparations to control tea insect pests.

“Great achievements in the application of physical and agricultural control methods in controlling the tea pests were advanced,” said Yajun et al. In Japan, China, and Malawi (Africa), yellow sticky traps and reflective films (near ultra-violet light) help control tea aphids, thrips, and leafhoppers (70-80% pest reduction). “A special mist wind insect-sucking machine was developed in Japan,” and it reduces tea leafhopper, whitefly, and spider mite populations.

Sex pheromones have been used for mating disruption in Japanese tea gardens since 1983 to control a pesky tea leafroller. Sex pheromones are also being used against other tea pests in Japan and China. Natural volatiles from the tea plant that attract natural enemies but not pests are also under development. For example, the April 2004 Chinese Journal of Applied Ecology (15(4):623-626) reported that beneficial lady beetles, green lacewings, and hover flys (syrphids) controlling tea aphids were attracted by natural compounds such as nerol from tea flowers, n-octanol from intact tea shoots, and geraniol, methyl salicylate, benzaldehyde, and hexanal from aphid-damaged tea shoots.

At Entomological Society of America (ESA) annual meetingss, California Department of Food and Agriculture (CDFA) officials report that T. Kanzawa’s 1939 translation of Professor Dr. Shonen Matsumura‘s 1931 book, 6000 Illustrated Insects of Japan-Empire, is still used to help with identification and control of invasive insect pests like the dusky-winged fruit fly (Drosophila suzukii). Oregon entomologist Jana Lee told the ESA that the Japanese get 100% fruit fly protection by placing 0.98 mm (0.04 inch) mesh over blueberries 20 days pre-harvest. After the harvest, 100% of fruit fly eggs and newly hatched larvae on cherries are killed by holding the fruit at 1.6-2.2 C (29-36 F). In Japanese experiments, fruit fly egg laying in cherries was reduced 30-60% with botanicals such as eucalyptus, neem, and tansy. In other promising Japanese research, Kotaro Konno and Hiroshi Ono told the ESA that latex from the same mulberry leaves used to safely grow silkworms since ancient times could be an effective botanical insecticide against other pests.

Since the 1920s, the USDA has been importing Japanese and Korean biocontrol organisms, like Tiphia wasps to control Oriental beetles and Japanese beetles attacking golf courses, turf, crops, and landscape ornamentals. Japan is currently patenting decoy tree technologies to help stop an explosive outbreak of oak wilt fungus (Raffaelea quercivora), caused by mass attacks of ambrosia beetles (Platypus quercivorus), said Masahiko Tokoro of the Forestry and Forest Products Research Institute (FFPRI) in Ibaraki, Japan (See earlier blog post: The Asian Invasion -Insects in Global Trade).

In South Korean greenhouse tests, Sangwon Kim and Un Taek Lim of Andong National University told the ESA of greenhouse tests showing the superiority of yellow circles against a black background versus conventional rectangular yellow sticky traps for capturing pesky whiteflies and thrips. “In laboratory behavioral studies using different backgrounds and shapes, yellow sticky card with black background was 1.8 times more attractive than sticky card without background, and triangle attracted 1.5 times more sweetpotato whitefly (Bemisia tabaci) than square,” said Kim. Black sticky cards with small yellow circles caught 180% more sweetpotato whitefly than cards with larger circles.

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.

Honey Bees, 24-Hour Surveillance Cameras & Pesticides

HONEY BEE HEALTH had the entomologists buzzing and the grad students searching for answers at the Entomological Society of America (ESA) annual meeting in San Diego. For several years now specialists have been spinning speculative theories as to why the pollinating honey bees of commerce, mostly the species known as Apis mellifera, have been in such sad shape. Isaac Newton had the proverbial apple bonk him awake to gravity. Bee entomologists have not yet had that magical bee sting in the butt “Aha” moment.

But there seems no getting away from the problem, as keepers of bee hives an ocean away from the USA are also getting stung with big losses, from what is dubbed colony collapse disorder (CCD). What has entomologists scurrying to their Petri dishes and bee hives and firing up surveillance cameras, chromatographs and mass spectrometers is a study titled “High Levels of Miticides and Agrochemicals in North American Apiaries: Implications for Honey Bee Health.” Christopher Mullin of The Pennsylvania State University, a self-described connoisseur of how poisons work, and several colleagues “found 121 different pesticides and metabolites within 887 wax, pollen, bee and associated hive samples” from 23 states and one Canadian province. Enough to induce sleep-loss and second thoughts about the health and sleep-inducing effects of commercial honey products.

Surveillance cameras, 24-hours a day, are the best way to monitor and gather numerical data on how pesticides affect honeybees, Cornhusker grad student Bethany Teeters told the ESA in her prize-winning poster, “Bees under surveillance.” Being more video than even an insomniac can sanely watch, the University of Nebraska-Lincoln entomology lab delegates the task to “state-of-the-art detection” software: namely EthoVision XT, which Noldus Information Technology calls “the most widely applied video tracking software that tracks and analyses the behavior, movement, and activity of any animal” from “lab animals in mazes to farm animals in stables.” No doubt what Geoge Orwell would have used in his Animal Farm novel, had he written it in 2011 rarther than 1946.

“Honey bees are exposed to sublethal doses of pesticides on a regular, often chronic, basis,” Teeters told the ESA. “For instance, the pyrethroid tau-fluvalinate (Apistan(R)) is one of many pesticides applied directly into the hive to control the parasitic mite Varroa destructor. Although tau-fluvalinate is considered safe for honey bees, potential effects of sublethal intoxication remain unexplored.” Same goes for coumaphos, also used to treat for Varroa mites.

“Honey bees may also encounter sublethal doses of pesticides while foraging,” said Teeters. “Systemic pesticides, including the neonicotinoid imidacloprid, have become prominent in U.S. crop pest management. This raises concerns about the consequences of sublethal exposure to systemic pesticides in nectar and pollen that honey bees visit in addition to chronic exposure to residues in the hive. Decline in colony health has been associated with ppm (parts per million) pesticide residues in hive products, and the neonicotinoid can impair honey bee health at ppb (parts per billion) levels.”

Teeters surveillance videos of bees exposed to sublethal pesticide doses in Petri dishes revealed that bees exposed to tiny traces of tau-fluvalinate spend more time socially interacting. Bees exposed to imidacloprid spend less time socially interacting and more time eating. Next step is studies to see if this is true in actual honey bee hives, and whether colony health is impacted.

Natalie Boyle, a graduate student at Washington State University in Pullman, studied the effects of Varroa mite pesticides on honey bee hives in Moscow, Idaho. Honey bee adults stressed by miticide residues died sooner and did less reproductive swarming. But they compensated with increased brood production. “While our results are preliminary, if we find that pesticide residues in brood comb adversely affect colony health, it would suggest that regular brood comb replacement in beekeeping operations might be a suitable management strategy,” said Boyle. “Similarly, approaches to reduce miticide applications in beehives and pesticide exposure in agricultural field settings would be highly beneficial.”

Back at The Pennsylvania State University, graduate student Daniel Schmehl noted that the Varroa mite-killing chemicals coumaphos and tau-fluvalinate were found in almost every honey bee hive sampled in North America. Furthermore, these two chemicals were “associated with reduced queen weight and reduced ovary development.” After six days chronic exposure to tau-fluvalinate in cage studies, worker bees were less attracted to queen bees. This was possibly “due to changes in pheromone production from the queen or pheromone recognition by the workers.”

On the West Coast, at the University of California, San Diego, graduate student Daren Eiri explored how sublethal doses of the pesticide imidacloprid can subtly alter foraging habits in ways that weaken honey bee colonies. A common lab assay used to assess foraging is stimulating the honey bee antenna with sucrose, which elicits the proboscis (tongue) extension reflex (PER). PER is the lab equivalent of natural honey bee behavior in the field when foragers are stimulated by nectar. The pesticide seemed to make the bees “become pickier when foraging for nectar sources, possibly limiting the colony intake and storage of their only carbohydrate.” Pollen foraging may also be reduced, and “the colony would therefore suffer a protein deficit, resulting in lessened brood production and a dwindling population.”

Though the mystery of colony collapse disorder (CCD) is far from solved, current agriculture practices do not seem to be making honey bee colonies healthier, to say the least. But the collapse of the imported honey bee may have a silver lining: It is spurring agriculture to turn to previously neglected native pollinators. But the rise of the native pollinators is another story, for another time.

The Asian Invasion -Insects in Global Trade

NATURAL WOOD PRODUCTS are better than synthetic petrochemical plastics is a common refrain, almost a rallying cry for many who consider themselves “green,” organic, sustainable or environmentally correct. Thus, the fashionable zeal in some sectors of society to ban plastic shopping bags and allow wood-pulp paper bags. But what if being “green” and using natural materials like wood instead of synthetic petrochemical plastics led to deforestation and pestilence? That’s pretty much the world trade situation these days.

At first glance wood pallets, crates, dunnage, and packaging materials seem to be the low-cost, sustainable “green” alternative vis-a-vis more expensive, synthetic petrochemical plastics. But wood packing materials used in global trade have spread a pestilence of native Asian wood-boring beetles to new homes worldwide. The North American invasion by Asian wood-boring species of bark beetles, ambrosia beetles, and long-horned beetles were among the hot topics at the Entomological Society of America (ESA) annual meeting of Dec. 2010 in San Diego, California.

Since hitchhiking to North America from Asia in solid wood packing materials and being detected near Detroit, Michigan in 2002, the wood-boring emerald ash borer has killed an estimated 30 million ash trees in the northern United States and southern Canada. The remaining North American ash trees are threatened. Though Sara Tanis, whose Michigan State University work is on You Tube, reported at the ESA annual meeting that blue ash (Fraxinus quadrangulata) “can withstand infestation and continue to survive.”

Emerald ash borer control is now multinational, involving the U.S. states of Michigan, Illinois, Indiana, Iowa, Kentucky, Maryland, Minnesota, Missouri, New York, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia, and Wisconsin plus the Canadian provinces of Ontario and Quebec. The Asian wood-boring beetle invasion is so far along it might make little difference if world trade abandoned wood pallets, crates, dunnage, and packing materials.

“Control strategies are now shifting to how we can manage established populations in the longer term,” Shajahan Johny of the Canadian Forest Service Great Lakes Forestry Centre in Sault Ste. Marie, Ontario, Canada, told the ESA. “One possibility is biological control, which is recognized as the most suitable long-term pest management strategy for invasive species.” Johny is looking at fungi in the genera Isaria and Paecilomyces attacking emerald ash borer in Ontario.

In Michigan and Ontario, Canada, the early emerald ash borer hot spots, woodpeckers can peck out up to half the wood-borers; which is good for the birds, but not stopping beetle movement to new trees. “In their native habitats, Agrilus (sci name of genus of 3,000 wood-boring beetles) populations are generally suppressed by a diverse group of natural enemies and/or host tree resistance, and rarely become serious pests,” said Jian Duan, Lead Scientist of the emerald ash borer biological control team at the USDA-ARS Beneficial Insects Introduction Research Unit in Newark, Delaware. The USDA has searched Russia, Mongolia, China, and South Korea to find specialized parasitoids that can be introduced to North America to hunt wood-boring beetle eggs concealed under loose bark and larvae hidden inside trees. The idea being to restore a natural ecological balance.

Asia has not been immune to wood-boring beetle outbreaks. “The mass mortality of oak trees (Japanese oak wilt) has recently increased explosively in Japan,” Masahiko Tokoro of the Forestry and Forest Products Research Institute (FFPRI) in Ibaraki, Japan, told the ESA. The Japanese are using a Decoy Tree Method (patent pending). Trap trees are baited with an aggregation pheromone attracting the wood-boring oak ambrosia beetle (Platypus quercivorus). Ethanol (alcohol) is added to the mix, because it is emitted by unhealthy or stressed trees and attracts beetles.

“Oak trees survive when they have been inoculated with a fungicide against the pathogenic fungus (oak wilt) before being attacked,” said Tokoro. “The decoy trees are lethal to the beetles because the symbiotic fungi (i.e. the ambrosia) that the beetles feed on are killed by the fungicide.” Neighboring trees can be similarly protected.

Variations on this method called push-pull are being developed in the U.S. to protect nursery trees from exotic ambrosia beetles (Xylosandrus spp.), said Christopher Ranger of the USDA-ARS Application Technology Research Unit in Wooster, Ohio. Ethanol is injected into sweetbay magnolia trap trees to stimulate ambrosia beetle attack. Beetles are “pushed” out of trees being protected by application of a repellent compound such as verbenone (dispensers) or via commercial botanical repellents such as Armorex, Veggie Pharm, Cinnacure. Azatin or Eco-Trol.

Compost for Sustainable Soil Fertility & Disease Suppression

ABOUT A THIRD of farm energy used for food growing supplies fertility. In Florida alone, the energy used to manufacture the 2 million tons of food crop fertilizer each year equals the energy content of 100 million gallons of diesel fuel. Thus, recycling or composting waste materials into fertilizers and mulches can save energy while reducing pollution and enhancing human and crop health.

In the book Farmers of Forty Centuries; Or, Permanent Agriculture in China, Korea and Japan, early-1900s agricultural scientist Franklin Hiram King observed amazing levels of soil productivity where rural and urban human wastes were recycled back to the land and farmers planted legume (e.g. soybean; adzuki bean; clover) and other green manure cover crops and crop rotations.

“Japanese society once faced the prospect of collapse due to environmental degradation, and the fact that it did not is what makes it such an instructive example,” writes Azby Brown in his 2010 book, Just Enough: Lessons in Living Green from Traditional Japan. “Japan entered the Edo period in 1603 facing extreme difficulties in obtaining building timber, suffering erosion and watershed damage due to having clear-cut so many of its mountains for lumber, and virtually unable to expand agricultural production…All the more remarkable, then, that 200 years later the same land was supporting 30 million people-2.5 times the population…Deforestation had been halted and reversed, farmland improved and made more productive, conservation implemented…Overall living standards had increased, and the people were better fed, housed, and clothed, and they were healthier. By any objective standard, it was a remarkable feat, arguably unequalled anywhere else, before or since.”

Human waste, euphemistically called night soil, became a valuable soil fertility commodity in old Japan. Perhaps not quite worth its weight in gold, but a valuable commodity bought, sold, traded, and transported long distances from cities to farms. Rather than causing cholera and other diseases by entering the water supply as was common in European cities of the same era, sanitation and composting blessed Japan with multiple dividends. Considerable energy was “expended on toilet design to allow these waste products to be easily collected and processed,” writes Brown. This has culminated in modern dry composting toilets that “by allowing natural composting heat to occur inside a well-ventilated compartment…turn human waste into a dry, nearly odorless compound that looks and feels like peat moss.”

Farmers in old Japan spent their own money to “build toilets and urinals along well-traveled roads for public use, in the hopes of increasing their yields of fertilizer.” Contrast this with the modern difficulty of finding a decent, well-maintained public toilet along roadsides or in cities. China, says Brown, “is poised to become the global leader in composting toilets, partly because relatively few communities are served by the sewer infrastructure and the government is promoting these new designs as an attractive alternative that will help mitigate its freshwater problems as well.”

In the modern Western world, scientists in Germany and the USA have advanced the conversion of animal manures and green plant wastes into composts and tea sprays that boost plant growth and suppress pests. Though long a staple of biodynamics and organic gardening, in the 1980s University of Bonn researchers like Heinrich Weltzien, Andreas Trankner and Ketterer provided experimental proof that watery compost tea sprays high in beneficial microbes reduced powdery mildew on grapes and late blight disease on potatoes. Indeed, in some experiments compost tea sprays formulated from grape marc, earthworm compost, and animal manures equalled synthetic fungicides.

In the USA, in 1969 reports surfaced that some Ohio nursery growers had conquered root rot diseases in rhododendrons, cyclamens, and other ornamentals using pine bark composts and no longer needed methyl bromide soil fumigations. Ohio State University’s Harry Hoitink embarked on scientific studies of this phenomena. To reliably control the plant pathogens causing root rots and other soil diseases, hardwood bark composts were aged like fine wines for 6-12 months or fortified with special biocontrol microbes. In Australia, eucalyptus bark is similarly composted to combat Pythium and Phytophthora root rot pathogens in container or potted plant soils and avocado orchards.

Insect pests can also be controlled with composts. For example, Cornell entomologists like Michael Villani and Roxanne Broadway stopped white grub beetle larvae from attacking turf and lawns using crude proteins extracted from composted leaves and kitchen food wastes. Composted chicken manure and feathers worked best against caterpillars (moth larvae). Cornell University’s Eric Nelson and others have spent years formulating composts to combat root rots on golf greens and maladies like dollar spot and brown patch.

It may take a year or two of aging to brew the right combination of pest-suppressive beneficial microbes in composts. In Japan, composted golf course grass clippings are specially inoculated with a strain of the beneficial bacteria Bacillus subtilis to hasten suppression of the fungus Rhizoctonia solani on golf courses.

However, compost is not always a quick cure. For example, several years of compost applications are needed to control soybean cyst nematodes in agricultural fields or to restore Japanese forest soils. That is because plant ecosystems are complex adapative systems.

Ozone Oxygen (O3) Fumigation for Organics

OZONE, A NATURAL OXYGEN (O3; 3 oxygen atoms) molecule that can also be synthesized, is among many other things an alternative to fumigants such as chlorine, methyl bromide, phosphine, and sulfuryl fluoride. Modern day humans have an almost schizophrenic, Jekyll-and-Hyde relationship with ozone, alternately and simultaneously seeking to eliminate and preserve ozone in the environment.

At stratospheric heights 12-15 miles (20-25 km) above the Earth’s surface, in what is called the ozone layer, 90% of the planetary ozone swirls and drifts about in molecular clouds, protectively absorbing mutation-inducing ultraviolet solar radiation wavelengths (also linked to immune disorders, cataracts, skin cancer, crop damage). For that reason an international treaty, the Montreal Protocol, was enacted in the mid-1980s to protect the ozone layer against known and unknown (to be discovered in the future) molecules destructive to ozone. That’s the good Dr Jekyll aspect of ozone (with apologies to Strange Case of Dr Jekyll and Mr Hyde author Robert Louis Stevenson).

Closer to Earth’s surface, where the 10% of planetary ozone not in the upper atmosphere resides, metropolitan areas such as Los Angeles and Phoenix suffer from ozone pollution and come under regulatory fire from the U.S. Environmental Protection Agency (EPA) because what is good 12 miles high is harmful at ground level. In “America’s Most Polluted Cities,” Forbes.com’s (04.28.10) Tim Kiladze calls it “harmful ozone, a ground level gas that contributes to urban smog and inflames the lungs, causing shortness of breath, wheezing and throat irritation.” The American Lung Association State of the Air 2010 report web site formulates EPA ozone and particle pollution data for American cities and counties into searchable form.

So, will ozone gas as an alternative to ozone-destroying fumigants like methyl bromide create more ground level ozone pollution or help replenish and preserve the protective stratospheric ozone layer?

“Chemicals can have their seasons, just like fashions. What one age admires as fine, another will reject as folly, and a good example of this is ozone,” writes John Emsley in his 1998 book, Molecules at an Exhibition. “A century ago ozone was also something to worry about, and for exactly the opposite reason: it was thought there was not enough of it around. Ozone was deemed to be natural, wholesome and invigorating, and the very locations where its levels were highest proved this: up in the mountains and along the coasts…Such was the esteem in which the Victorians held ozone that they had generators pumping it into churches, hospitals, theatres and even their underground railways.”

At the 2009 Entomological Society of America (ESA) annual meeting in Indianapolis, ground-level ozone was back in fashion as an environmentally-friendly fumigant molecule (unstable; decomposes quickly). Methyl bromide (another natural molecule) faces demise as a fumigant under the Montreal Protocol for destroying ozone. And stored grain insect pests are becoming resistant to phosphine. Carbon dioxide, a waste gas exhaled by humans and a feedstock of sorts for green plants, has some fumigant potential but is too slow-acting and unfashionable as a warming greenhouse gas.

Though it is easy to pump ozone through hoses into grain bins, ozone does not penetrate the dense grain well and fumigations can last 3-10 days. Purdue University’s Marissa McDonough noted that the grain is more quickly disinfested of red flour beetles (Tribolium castaneum), maize weevils (Sitophilus zeamais) and other pests by physically moving the grain in layers exposed to ozone sprays in passing.

Potency, ease of use, and low cost make for a good fumigant, said Kansas State University’s Mahbub Hasan, who noted that phosphine, sulfuryl fluoride and ozone are all potential alternatives to methyl bromide fumigation for dry-cured hams attacked by red-legged ham beetles (Necrobia rufipes), ham mites (Tyrophagus putrescentiae), cheese skipper flies (Piophila casei) and carpet beetles (Dermestidae). Carbon dioxide was too slow, said Hasan, taking six days to knock out ham mites. An integrated (IPM) approach combining biological controls, cooling, pheromone traps, ozone and botanical fumigants may ultimately be devised for protecting stored foodstuffs.

However, ozone remains out-of-favor in the plant world. “Tomato plants may be more susceptible to wounding by caterpillar pests in ozone than in ambient air,” Western Illinois University’s Sue Hum-Musser told the ESA meeting in Indianapolis. “Several genes play important roles in plant defenses against the combined stress of ozone and insect herbivory. Increasing ozone levels cause damaging effects on the plant community, and insect pests cost billions of dollars to agriculture.”

Fashion is a fickle thing, and future ozone fashions will likely remain a twenty-first century Jekyll and Hyde muddle.

Richard Feynman’s Nontoxic Ant Ferry

RICHARD FEYNMAN, CALTECH’S Nobel Prize winning physicist (1965; quantum electrodynamics), was a Princeton University graduate student during the early years of World War II when foraging ants crawled in his bay window and spurred development of an ant control device that did not kill the creatures. It was not quite as momentous as the proverbial apple conking Isaac Newton on the head in 1666 and waking him up to gravity. But according to Mathpages.com, Feynman’s “analysis of the behavior of ants involves some of the same ideas that were central to his work in theoretical physics.”

On a more mundane note, Feynman recounts the experience in his 1985 book, Surely You’re Joking, Mr. Feynman!: “In Princeton the ants found my larder, where I had jelly and bread and stuff, which was quite a distance from the window. A long line of ants marched along the floor across the living room. It was during the time I was doing these experiments on ants, so I thought to myself, ‘What can I do to stop them from coming to my larder without killing any ants? No poison; you gotta be humane to the ants!’”

Interesting sentiments coming from a man who worked on the Manhattan Project in New Mexico to help develop atomic energy into the bombs dropped on Japan to end World War II. But, of course, the goal of the Manhattan Project was to build the bomb ahead of Hitler’s scientists working in Europe. Peace and freedom were envisioned at the end of the atomic trail.

“One question that I wondered about was why the ant trails look so straight and nice,” wrote Feynman in his oft-reprinted 1985 book. “The ants look as if they know what they’re doing, as if they have a good sense of geometry. Yet the experiments that I did to try to demonstrate their sense of geometry didn’t work. Many years later, when I was at Caltech and lived in a little house on Alameda Street, some ants came out around the bathtub. I thought, ‘This is a great opportunity.’ I put some sugar on the other end of the bathtub, and sat there the whole afternoon until an ant finally found the sugar. It’s only a question of patience.”

Today we know that ants are putting down a pheromone trail, and that over time the trails most frequented (i.e with food at the end) get a stronger dose of pheromone while the pheromone disappears from the least-wandered trails. Feynman’s observations are called Ant Logic or Ant Colony Optimization by those who, in or out of the bathtub, today study the trail-following process, oftentimes using virtual ants in computer simulations for Internet routing, robotics, and business and travel solutions.

Apparently, via pheromone trails between their nest and food resources, in their everyday life ants have mastered a workable solution to what is called The Traveling Salesman Problem, which the web site of the same name (abbrev. TSP) calls “one of the most intensively studied problems in computational mathematics.”

Planning the best route between a hundred cities for a traveling rock band or the quickest path for sending data packets among thousands of Internet nodes on the Worldwide Web can apparently overheat and exhaust modern computers. In a chapter titled “Ant Logic” in The Perfect Swarm, book author Len Fisher says: “To calculate the optimal route that Ulysses might have taken between the 16 cities mentioned in The Odyssey, for example, requires the evaluation of 653,837,184,000 possible routes.” That works out to “ten thousand billion calculations” for a relatively simple travel problem.

Fortunately, Nobel Prize-caliber calculations were not needed to disrupt ant trails and humanely protect Feynman’s Princeton larder or Pasadena home. ANT FERRY was the name Feynman gave to his least-toxic ant removal device: “I made a lot of little strips of paper and put a fold in them, so I could pick up ants and ferry them from one place to another,” wrote Feynman in Surely You’re Joking, Mr. Feynman!.

“What I did was this: In preparation, I put a bit of sugar about 6 or 8 inches from their entry point into the room, that they didn’t know about. Then I made those ferry things again, and whenever an ant returning with food walked onto my little ferry, I’d carry him over and put him on the sugar. Any ant coming toward the larder that walked onto a ferry I also carried over to the sugar. Eventually the ants found their way from the sugar to their hole, so this new trail was being doubly reinforced, while the old trail was being used less and less. I knew that after half an hour or so the old trail would dry up, and in an hour they were out of my larder. I didn’t wash the floor. I didn’t do anything but ferry ants.”

No Nobel Prize is needed to obliterate ant trails and naturally protect larders without toxins or even killing any ants. However, the patience, the extra hour, may be outside the modern mindset. Nonetheless, thank you Mr. Feynman for what your colleagues call a PROOF of CONCEPT.

Honey, Bees, Better Sleep & Memories

“A TEASPOON OR TWO of honey before bed insures a restorative sleep,” writes Reese Halter in his informative little book, The Incomparable Honeybee & The Economics of Pollination. “A human liver stores about eight hours of glycogen – an important brain food. If you eat supper at 7 pm, by about 3 am your brain releases a stress hormone called cortisol. Cortisol scavenges the body, melts muscle tissue and converts it into glycogen to feed the brain. When released, cortisol causes the heart to beat faster and raises glucose insulin levels in the blood. Elevated cortisol can lead to obesity, diabetes, coronary disease and autoimmune breakdown. A teaspoon of honey at night fuels the liver with glucose and fructose, which is absorbed slowly – thus providing a restful sleep and preventing the release of cortisol.”

Perhaps honey also helps bees with their sleep?

In the 27 March 2010 Philosophical Transactions B of the Royal Society, researchers Timothy C. Roth and Vladimir V. Pravosudov at the University of Nevada, Reno, and Niels C. Rattenborg at the Max Planck Institute in Germany “examine the ecological relevance of sleep” for “memory/learning and hypothermia/torpor to conserve energy.” Sleep, it seems, is still a somewhat mysterious function. However, sleep in honeybees and other animals lends itself to ecological and experimental study.

Honeybee sleep is not exactly the hottest research topic on the planet at the moment. But that may change as the links between honeybee sleep, pathogen spread, and diseases are further explored. At past Entomological Society of America (ESA) meetings, Barrett Klein, who is finishing his Ph.D. in Ecology, Evolution and Behavior at the University of Texas in Austin, has attracted more attention for his entertaining role in insect art symposia.

At the Biozentrum in Wurzburg, Germany, Klein used an infrared camera to measure temperature changes and map sleep patterns of Carniolan bees (Apis melifera carnica) as they aged and changed tasks over time. Young worker bees progress from cleaning hive cells to nursing to food storage to foraging as they age.

Older forager bees sleep mostly at night, outside of cells, close to the edge of the hive where it is coldest. Younger cell cleaning bees sleep day and night, mostly inside cells where it is warmest. Foraging honeybees are the caste most likely to bring pathogens back to the hive. Thus, sleeping at night in the cold near the edge of the hive away from the warm brood reduces the potential for pathogen spread to the rest of the hive.

In the journal Learning & Memory, researchers in Germany used a web camera to “address the question if sleep in bees, like in other animals, improves memory consolidation.” Indeed, the webcam revealed that sleep deprivation had some negative effects on honeybee memory. At the ESA, Edgar Hernandez of the University of Missouri in St Louis described some of the work with “clock genes” and “clock proteins” playing a role in determining when bumble bees sleep.

With honeybees in trouble due to colony collapse, bumble bees and native bees are getting more attention. Nancy Adamson of Virginia Tech reported to the ESA that the honeybee situation has become so worrisome that the Virginia State Legislature voted to support research “aiming to provide information to Virginia farmers interested in supporting a broad spectrum of pollinators on their crops.” This includes providing harborage and habitat for bumble bees and other native bees.

“North America boasts over 4,000 species of native bees, many of which could serve as crop pollinators,” said Ann Fraser of Michigan’s Kalamazoo College. Native bees and bumble bees can pollinate crops on cloudy days and in cooler weather when honeybees are less active. Indeed, New Jersey and Pennsylvania watermelons are pollinated by 46 native bee species. In New York pumpkin fields, more bumble bee visits means heavier pumpkins, said Cornell’s Derek Artz.

Native bees and bumble bees can also be part of urban renewal. According to Ohio State University’s Scott Prajzner, vacant land within the city centers of Akron and Cleveland now supports community gardens and urban farms. This has boosted populations of native squash bees (Peponapis sp) and long-horned bees (Melissodes sp).

Perhaps we will all sleep better and have a more sustainable food supply by getting back to the basics: Honeybees for honey production, and letting bumble bees and native bees handle more crop pollination.

Natural vs Synthetic Repellents

SYNTHETIC OR NATURAL? Which is best? Since the 1950s the synthetic chemical DEET (N, N-diethyl-m-toluamide) has been the standard to which all other mosquito, tick and biting fly repellents have been compared. DEET is still the standard of comparison, but the long search for natural or organic repellents is finally yielding a number of potential alternatives, some from the plant world and others from such unlikely places as human sweat.

The progress in besting DEET has been so stunning that the Entomological Society of America (ESA) presented a four-hour symposium with a dozen 20-minute talks, Celebrating the Success of Global Insect Repellent Science Research. Habitues of the ESA know that in the world view of a female mosquito, humans are little more than scented apes put on Earth to be protein-rich blood meals to begat new generations of what we call vermin and they consider kin.

Sweat, heat, and carbon dioxide, that greenhouse gas that humans respire into the atmosphere with every exhaled breath, tip off mosquitoes and other bloodsuckers that the human food wagon has arrived. Actually, that’s putting it a bit crudely. Mosquitoes are actually connoisseurs, and sniff out humans like a gourmet would a fine wine. To be even more accurate, females are the true connoisseurs and gourmands, the bloodsucking vampire sex of the mosquito world. Male mosquitoes are true flower children, pacifists abhorring the bloodsucking life and mostly passing the time pollinating plants.

Longtime scholars of mosquito feeding habits on humans, like Willem Takken at Wageningen University in The Netherlands, have tallied 300 to 350 compounds mosquitoes can use to identify humans. About 60 of these odors are common to every person, and the rest give each human a slightly different scent. Thus, we oftentimes remember a person by their distinctive smell. Elegant experimental techniques like gene silencing and transferring mosquito olfactory genes to fruit flies allows the mapping of mosquito odor preferences. Some mosquito species, such as the malaria-vector Anopheles gambiae, can zero right in on humans. Other mosquito species may bypass humans in favor of cows, livestock or other animal species.

From a practical standpoint, if diseases like malaria, dengue and yellow fever are not a concern and you need protection for only an hour or two, one of the many commercial botanical repellents is likely to suffice as an alternative to DEET. Lemon eucalyptus products, including Quwenling from China, get high marks from the CDC. Daniel Strickman at the USDA-ARS in Beltsville, MD, and others have compiled long lists of botanicals good for about an hour of repellency, including: clove, geranium (geraniol), citronella, celery, lemon, lime, neem, pyrethrum, fringed rue, patchouli, pennyroyal, soybean, thyme, niaouli (Melaleuca viridiflora), makaen (Zanthoxylum limonella), Mexican tea (Chenopodium ambrosioides), Labrador tea (Ledum groenlandicum), and lily-of-the-valley.

However, natural or organic does not automatically mean safe or lacking in toxicity. Natural compounds, like synthetics, can also be sources of skin irritation, toxicity, and carcinogenicity. Even lemon eucalyptus oil can be an eye irritant. And as some herbal tea drinkers have learned the hard way (as is documented in the medical journals), the active ingredients in pennyroyal, violets and other botanicals can be dangerously toxic in too high a dose or with prolonged use.

The U.S. EPA can give what is known in legalese as FIFRA 25(b) Exemptions (Minimum Risk Pesticides), the USDA’s Strickland told the ESA repellent symposium. This allows some natural compound active ingredients to be used as repellents without testing. Examples include cedar oil (from eastern red cedar), citronella, garlic, geranium, lemongrass, peppermint, soybean oil and thyme. The International Fragrance Association investigates active ingredients to avoid lawsuits over cosmetics, though even this is not a guarantee against allergic reactions.

In short, caution is the watchword. Try a little bit first, and to be really safe use long sleeves and pants so that minimal repellent directly contacts the skin (as both natural and synthetic chemicals may penetrate the skin and enter the bloodstream).

Joel Coats’ lab at the University of Iowa provided the ESA symposium with a glimpse of the future. Coats’ lab is well-known in entomological circles for its pioneering work with naturally occurring monoterpene and sesquiterpene chemicals in plants such as catnip (Nepeta cataria), Osage orange (Maclura pomifera), West Indian sandalwood (Amyris balsamifera), and Siam-wood (Fokenia hodginsii). In short, the chemicals known as monoterpenes provide a broad spatial repellency, and the “oxygenated sesquiterpenes” provide contact repellency. And a mixture of the two provides both modes of action and the best repellency. You will probably want to wait for the testing to be completed and commercial products to be formulated.

But back to the question of which is best, natural or synthetic. Some of the best natural compounds, and there are too many to list, can outperform DEET. Even some new synthetics can outperform DEET in some ways. If you have a job that keeps you in the field and exposed to mosquitoes, biting flies and ticks for 12 or 24 hours at a time, then you need some heavy-duty, long-lasting protection. Indeed, that is the holy grail for organizations like the U.S. Army.

Life may have seemed simpler in the 1960s when Mr. Robinson told Dustin Hoffman in the movie The Graduate that the future was in plastics. Quantitative structure-activity relationships (QSAR) is the future in 2010, say Coats and his graduate student Gretchen Paluch. They forsee a leapfrogging future where natural repellents better than DEET lead to new synthetic spinoffs of nature’s best molecules better than anything yet known.

They believe that patchouli, cedar oil and other natural compounds can (via QSAR) provide the skeleton for designing new repellent molecules. However, it may not be so simple, as a fine ecological balance has evolved in nature. Though it may seem contradictory, even so-called repellent plants like catnip, which is famous for repellent molecules like neptalactone, also contain attractant molecules. Possibly the best repellents will also contain elements of attraction. But that is another story for another time.

Play a Beetles Song, Protect a Tree

TEXAS GAVE US Buddy Holly and the Crickets; Liverpool, England, the Beatles. Far from competing in the musical arena with the Crickets or challenging Liverpool’s Fab Four, forestry entomologists across the border from Texas in neighboring Louisiana (as well as in Arizona) are tuning into wild Beetle chirping songs to learn how to broadcast a sound, nontoxic form of pine forest bark beetle control.

The Beetles are an unusual group in the animal world. Known to entomologists as the insect order Coleoptera, “Beetles make up 40% of all insects and there are eight times as many beetle species as there are fish, amphibian, reptile, bird and mammal species put together.” The beetle-friendly, Australian Museum web site in Sydney also says: “There are over 350,000 different known beetle species worldwide and new species are being discovered all the time.” More likely the total number of known and unknown beetle species is in the millions; no one, not even Wikipedia, knows for sure.

Beetle lovers, besides having many new species still available to discover and describe, are finding gainful employment keeping up with the more pestiferous species. From downtown Chicago to New York City’s Central Park, Asian longhorn beetles have been famously chomping away at urban forests. In Michigan alone, the emerald ash borer has felled 50 million ash trees in recent years. And this is only scratching the surface of what is out there, and has spread worldwide via wooden shipping pallets, tourists, trains, planes and ships.

Though most beetle species are benign or beneficial, the fight against the more pestiferous species generates a range of interesting research presentations at Entomological Society of America (ESA) meetings. For example, just northeast of Los Angeles in the southern California county of San Bernadino, USDA Forest Service researchers such as Andreana Cipollone are testing SOLARIZATION to stop firewood transport from spreading goldspotted oak borer (Agrilus coxalis), a pesky beetle infesting 50% of oak trees and killing over 22,000 oaks in the infestation zone. Solarization involves covering firewood cords or piles with aluminum mesh screening or plastic tarps to solar-cook the wood and kill or stop beetle emergence.

In the southeastern United States, the southern pine beetle (Dendroctonus frontalis) is the most economically damaging pine pest, causing over $2.5 billion in damage in the last decade. Large numbers of this aggressive bark beetle gang up on and overcome the defenses of healthy trees. Female beetles attract male beetles with sex pheromones; arriving males stridulate (rub together body parts) to produce a double-duty chirping song that wards off rival males and attracts females. Females produce their own chirping song to keep other females at a distance, which gives the offspring more room to develop inside the tree galleries.

“We intend to explore the possibility that song playback devices may find utility in manipulating southern pine beetle behavior at the scale of single trees, and thereby might offer a non-chemical means of tree protection,” reported Christof Stumpf of Louisiana State University at the December 2009 ESA annual meeting in Indianapolis. At the same ESA meeting, Richard Hofstetter of Northern Arizona University in Flagstaff noted that Arizona bark beetles can also be defeated with their own songs. But according to Arizona Republic reporter Shaun McKinnon (Feb. 09, 2010) and Discovery News reporter Jennifer Viegas (Feb. 10) the Arizona bark beetles were not deterred by Heavy Metal rock music or Rush Limbaugh radio broadcasts played backwards or forwards.

Evidently, we must tune into the sounds of nature itself and not rely on either political commentators or rock musicians to solve our pest problems for us.

Headless Zombie Fire Ants, Brain-Eating Flies!

FIRE ANTS ATTACKED by BRAIN-EATING FLY MAGGOTS, transformed into HEADLESS ZOMBIES. So says the ever-helpful Kavita Sharma, an Auburn University entomologist in fire ant-plagued Alabama, a likely port of disembarkation for the painfully-biting red imported fire ant invasion of the United States that began in earnest during World War II.

If you missed it on the evening news or failed to scan the supermarket tabloid headlines, the Internet tabloid journalists have had fun dramatizing it on You Tube. Not that the brain-eating flies have yet provided much relief from the ever-expanding, biting fire ant invasion raging from Texas, Oklahoma and New Mexico to Florida and the Carolinas. Indeed, the ants may be bent on global colonization, having expanded from their South America homeland in Argentina to North America, Australia and other continents.

Several decades of pesticide spraying, and more recently poison baits, have done little to slow the spread of the biting ants, which have effectively colonized the southern U.S. and seem to be adapting to slightly cooler northern climes. Not that it is all bad, if you can avoid being bitten. The ravenous ants provide vital biological pest control on some farms; for example ridding cotton farms of bollworms, weevils and other pests that would otherwise be sprayed with pesticides. No doubt, the ants would also make mincemeat and hash out of any bedbugs in an infested mattress placed in their path.

But the pain of the bites and the problematic fire ant mounds erupting in lawns and pastures necessitate control measures. As is typical of pest control programs, years of failed but costly chemical eradication eventually breed pesticide-resistant insects. Score one point for the fire ants and Darwin’s theory of evolution. Score good revenues for valiant pest control efforts. But longer term, insect genetics adapt to almost anything thrown at them.

In the 1954 sci-fi flick, Them, even Fess Parker (Davy Crockett fame), Leonard Nimoy (an uncredited, pre-Star Trek role) and James Whitmore’s bullets failed to stem a mutant ant invasion linked to atomic tests. But James Arness (of later Gunsmoke fame) finally routed the giant mutant ants colonizing downtown Los Angeles with an orgy of messy napalm-like flame throwers. Poison baits minimizing environmental contamination and brain-eating flies providing biological ant control look elegant in comparison. Indeed, pest control has come a long way in the half century since Rachel Carson railed against pesticides.

In her poster display at the Entomological Society of America (ESA) annual meeting in downtown Indianapolis, Kavita Sharma provided scientific details on how the brain-eating phorid flies locate fresh worker fire ant brains and turn the ants into zombies. Pheromone-like chemicals may be involved. One of the phorid fly species introduced into the U.S. from Argentina for fire ant biocontrol is literally super-efficient and would make time management experts proud. When not in the maggot stage eating ant brains, adult flies combine mating with searching out worker fire ants with nourishing brains to attack. No doubt more to come on You Tube’s Zombie Ant Channel.

Pirate Ships & Trojan-Horse Bed Bugs

BED BUGS PLAGUE houses, apartments, hostels, hotels, motels, barns, caves, and even ships on the high seas. There is no escaping bed bugs, even for frigates, warships, passenger ships and pirate boats plying the world’s oceans. If you doubt it, just talk to U.S. Navy entomologists like David Claborn at the Entomological Society of America (ESA) meetings.

Cockroaches, rats, lice and bed bugs sometimes outnumber sailors on ships at sea. About the time of the American Revolution, in the 1770s, ships were often such damp, putrid, scurvy-ridden pest-holes that half the crew would be sick during the voyage. And mortality was high. Captain James Cook of Great Britain’s Royal Navy was one of the early advocates for bringing ship hygiene up to modern standards.

Scrubbing decks with dilute solutions of sweet-smelling vinegar was one of Captain Cook’s practices to keep rats, lice, bed bugs and cockroaches at tolerably low levels. Caribbean pirate ships, a less sanitary lot, used “primitive fumigation techniques” like placing “tubs full of flaming tar and sulfur inside the hulls to kill the vermin and improve the odor,” said Claborn. Infestations were sometimes so bad that brandy casks were poured onto the decks as mop water and scrubbed into the wood.

In the modern world of asymmetrical warfare in the pirate-ridden waters off the coast of East Africa, bed bugs and other vermin have been used like weapons by the pirates. When a small pirate boat fired a rocket on a U.S. Navy ship, the U.S.S. Fearless, a wooden minesweeper, took action. The Fearless scooped up the pirate boat into its well deck. The well deck, a dock for floating military equipment, was raised up and the pirate ship came to rest high and dry.

“That’s when the insects and the rats started leaving the boat, perhaps lonely for the recently incarcerated pirates,” said Claborn. “When the corpsmen called me from the ship they reported, and I quote this: ‘at least three species of cockroaches, bed bugs, spiders, rats and some really scary things that we don’t recognize’. Our immaculately clean warship now has a Trojan horse populated not with Greek warriors, but with bed bugs, cockroaches and rats.”

Just like on land, the bed bugs and their harborages were hard to find and hard to disinfest. A minor victory for the pirates. All infested shipboard items had to be discarded, all the fabrics washed, and crack and crevice residuals were sprayed to stop the bed bugs from biting.

Interplanting, Ancient Roots

INTERPLANTING IS ANCIENT. It predates agriculture. Interplanting even predates the dinosaur, going back to the first plants growing side-by-side on planet EARTH. Indeed, interplanting is a natural ecological phenomena, existing much like the stars in the night sky.

On farms and gardens, interplanting is sometimes called companion planting. Ancient farmers observed natural interplanting or companion planting in their fields, along with winds, rains, heat, cold, insects, solstices and lunar and planetary movements across the sky. Today, much of the natural interplants occurring in farm fields and gardens is derisively referred to as weed growth (though major crops like maize and wheat still contain the genes of weed ancestors). Indeed, it is a value judgment when native wildflowers like prairie sunflowers are labeled weeds and destroyed by cultivation or herbicides.

In the U.S. state of Tennessee in the 1930s, during America’s Great Depression, the insect factor in interplanting was first subjected to scientific experimentation by an entomologist named Marcovitch. Writing in a 1935 issue of the Journal of Economic Entomology, a still extant publication of the Entomological Society of America (ESA), Marcovitch traced his interest to experiment station reports by other entomologists. Much like the ancient farmers who based planting decisions on empirical and astronomical observations, an entomologist writing in 1906 “advocated for the control of the melon louse the planting of mustard or kale or rape around the melon field. The lady beetles would thus become plentiful after feeding on the cabbage aphids and be ready to attack the melon louse.”

Marcovitch’s penchant to begin the modern era of experimental companion planting was also inspired by a 1929 entomological report that woodlots fostered populations of aphid-eating syrphid flies that destroyed aphids in garden peas. In contrast, pea fields away from woodlots were devastated by aphids and sometimes yielded no crop. Figuring that aphid damage to vegetables was a consequence of an absence of biological control by aphid natural enemies, Marcovitch began a series of scientific interplanting experiments to boost natural biological control in crop fields.

Tennessee turnip strips planted in March yielded aphid natural enemies like lady beetles and small parasitic wasps that migrated later into adjacent strips of peas, beans, corn, okra, cotton, cucumbers and watermelons. Aphid populations declined in the main crops, thanks to the adjacent natural enemy-laden turnip rows. In contrast, “control” watermelon plots lacking adjacent turnip rows to provide natural enemies were destroyed by aphids early in the season.

Since Marcovitch’s pioneering 1935 report in the Journal of Economic Entomology, books have been written on interplanting experiments to increase natural biological control in crops.

Beneficial Bugs Challenge Theoretical Physics

INSECTS, MICROBES, PLANTS and other organisms form complex ecological systems with all sorts of synergisms, antagonisms and cooperative interactions, leading oftentimes to beneficial insects controlling what we consider pests. Whether it be forest, desert, farm field or garden, intricate and nuanced ecological communities can be nurtured to provide a measure of “natural” biological pest control.

The nuanced complexity of biological and ecological systems has at times intrigued theoretical physicists usually more attuned to quarks, neutrinos, chaos theory and quantum phenomena. Murray Gell-Mann, winner of the 1969 physics Nobel Prize as a Caltech (Pasadena, California) professor “for his contributions and discoveries concerning the classification of elementary particles and their interactions,” created the Santa Fe Institute (New Mexico) to better focus on “the theory of complex adaptive systems.”

Humans, plants and animals are individually and collectively at the ecosystem level examples of complex adaptive systems. Which is one reason creating sustainable agriculture is such a challenge, and companies such as Rincon-Vitova Insectaries end up with catalogs of 55 pages of beneficial insects, microbes, seeds, traps and other inputs for creating sustainable garden and farm systems. And even then, it is not always easy and can take longer than expected to force changes in even the smallest complex adaptive system that is a backyard garden.

“Unfortunately, it will be a long time before human knowledge, understanding, and ingenuity can match–if ever they do–the “cleverness” of several billion years of biological evolution,” wrote Gell-Mann in his book, The Quark and the Jaguar. “Not only have individual organisms evolved their own special, intricate patterns and ways of life, but the interactions of huge numbers of species in ecological communities have undergone delicate mutual adjustments over long periods of time.”

Rainy Days Wash Pests Away

WORLD WAR II was raging around The Netherlands from 1941 to 1944. But in Zeeland province entomologist D.J. Kuenen slogged on with his solitary, long-term studies of climate and rainfall effects on fruit tree red spider mites in apple and plum orchards. Even under the best conditions in peacetime, long-term ecological field studies that could aid in natural pest control are few and far between. The reason is simple: longterm ecological field studies are an expensive, labor-intensive, problematic way to advance a career in academia. The more-assured path to tenure and gainful employment is a series of quick, narrowly-focused lab studies yielding a plethora of speedily published papers in scholarly journals.

DDT and the synthetic pesticide era, along with high-yield chemical farming, exploded in the years immediately after World War II. The tedious years of meticulously gathered data on natural pest control from wind and rainfall (a form of overhead irrigation) was consigned to languish for decades under layers of library dust in tiny articles in obscure journals. Kuenen and his predecessors studying the pest control efficacy of wind and high-pressure water sprays were several decades ahead of their time. Much like the monk Gregor Mendel’s now-celebrated genetic experiments growing wrinkly and smooth garden peas.

Today, the pendulum is swinging back to more natural forms of pest control. Kuenen and his Roaring Twenties predecessors studying wind and rain as natural forms of pest control would be warmly welcomed at sustainable agriculture gatherings today. Ecological field studies showing that heavy rain showers and wind storms blasted away 90% of pesky spider mites would be spurring graduate students and inventive farmers to simulate the natural pest control benefits with artificial wind and water blasts from hoses, sprinklers, and other devices.

Pheromone Revolution Hits Half Century Mark

HALF a CENTURY ago the PHEROMONE REVOLUTION commenced in earnest. German chemist Adolf Friedrich Johann Butenandt opened the floodgates as lead author of an article announcing the isolation and chemical identification of a sex pheromone female silkworm moths produce to attract male mates. Butenandt had already shared the 1939 Nobel Prize in chemistry for discovering human reproductive steroid hormones. So the 1959 article announcing the first pheromone in the monthly chemical science journal Zeitschrift für Naturforschung B (14B:283-4) attracted the attention of Rachel Carson and stimulated the efforts and imaginations of many others searching for insecticide-reducing alternatives.

HALF a MILLION virgin female silk moths were sacrificed over a span of almost THREE DECADES to identify that first sex pheromone, named bombykol because Bombyx mori is the scientific name of the Chinese silk moth of textile fame. In the past half century, thousands more pheromones have been identified, mostly from pest insects of economic interest. But also increasingly from beneficial insects providing biological control.

According to researchers like Jeffrey Aldrich at the USDA-ARS Chemicals Affecting Insect Behavior Laboratory (CAIBL) in Beltsville, MD, the potential applications of natural enemy pheromone and semiochemical research, such as herding beneficial insects into crop fields where they are needed, is still in its infancy. Projects include using pheromones to increase biocontrol by predatory spined soldier bugs (Podisus maculiventris). These beneficial stink bugs are capable of biologically controlling pesticide-resistant Colorado potato beetles, Mexican bean beetles, and cabbage and tomato caterpillars.

One idea is using pheromones to trap natural enemies, and then creating mini-insectaries by placing cages full of natural enemies into crop fields and landscapes. Predator production can be maximized with “an in-field nursery where we are putting these trapped bugs right inside of the (mesh) cage” over plants in the field, said Aldrich. “You pick a mesh size where the adults can’t get out, but when they lay eggs then the nymphs can walk out and start feeding on pest species in the vicinity.” In field tests, potato defoliation was reduced and yield significantly increased.

In bean field tests, spined soldier bug nymphs walked upwind towards an aggregation pheromone. In sequential plantings, this technique could be used by farmers to move or herd predators out of maturing fields into more newly planted fields. Pheromone technologies are also being explored to maximize biocontrol by minute pirate bugs, big-eyed bugs, tachinid flies, and other natural enemies.

Lacewing Silk

GREEN LACEWING consumption of moth eggs, small caterpillars, spider mites, aphids and other pests promotes sustainable biological pest control in farms, gardens, greenhouses, zoos, malls, conservatories and other landscapes. Sustainable cotton farmers around the world have long utilized green lacewings for biocontrol, but few ever had an inkling that both cotton AND lacewings could be fiber crops. Indeed, biocontrol companies like Rincon-Vitova Insectaries, which has a green lacewing logo, may one day be garbed in garments woven from organic cotton and green lacewing silk.

Not that green lacewing silk is likely to make a major fashion splash anytime soon or displace traditional mulberry-reared silkworm cocoon threads. Rather, adding another insect silk to the textile design palette is just another milestone marker from several decades of studying the chemistry, genetics, biology, physics, acoustics, ecology, etc. underlying biocontrol by green lacewings. The latest technical details from Australia’s Commonwealth Scientific Industrial and Research Organisation (CSIRO) on the superior textile properties of green lacewing egg-stalk silks is just one more brick in the ecological edifice.

Ecologically, besides finding shelter from the elements and locating nourishment, the real world for an insect is also a constant struggle to avoid being prey to natural enemies. Even pest natural enemies like green lacewings are preyed upon by their own set of natural enemies (e.g. spiders, bats, parasitic wasps, ants). Lacewings adapt by eavesdropping on bat echolocation signals (a form of radar used for navigation and prey detection) and flying evasive flight patterns. Green lacewings trapped in silken orb spider webs have their own almost ritualistic behaviors for chewing themselves free, and tiny wing hairs are designed to smoothly slide free from sticky spider webs.

Thin tough silken egg stalks that are strong yet flexible loft green lacewing eggs safely out of the reach of marauding ants. For extra protection, the high-protein silk egg stalks are also coated with oily ant repellent chemicals. Interestingly, the egg stalk silks are very different from green lacewing cocoon silks. Textile buffs are intrigued, as egg stalk silks rapidly solidify after being secreted as liquid droplets that are extruded into thin strong fibers swaying like palm tree trunks topped with lacewing eggs.

From an engineering standpoint, these green lacewing egg stalk silk properties suggest the possibility of new industries and biological silk factories. In a future decade, green lacewing silk may be woven along with silkworm silk and cotton into apparel and furnishings. An unexpected dividend from years of research related to green lacewings and biocontrol.

Wintergreen = Biocontrol Aromatherapy

WHEN ENTOMOLOGISTS hip to chemical ecology speak of HIPPOs, they mean HERBIVORE INDUCED PLANT PROTECTION ODORS, not the massive hippopotamus native to riverine Africa. At Washington State University (WSU), David James and his entomological colleagues have spent the last several years testing fragrant wintergreen oil, a common HIPPO produced by distressed plants, as a means to boost biological control of crop pests by natural enemies.

The same fragrant wintergreen oil (high in methyl salicylate) used in mints and mouthwashes can be formulated into slow-release dispensers to attract beneficial insects into crops in greater numbers earlier in the season than would otherwise be the case. The dispensers minimize environmental and worker health impacts and crop damage (phytotoxicity). Also, the dispensers can last 3-4 months, providing extended periods of natural enemy attraction. Sprays evaporate more quickly, potentially meaning more applications. Nevertheless, spray technologies are still very popular and 2% wintergreen oil in canola oil is being test sprayed worldwide in crops ranging from hops and cotton to soybeans, strawberries and sweet corn.

In their earliest hop yard and grape vineyard field tests, James and his coworkers found that wintergreen oil attracted significantly higher numbers of pest natural enemies like predatory green lacewings, minute pirate bugs (Orius spp.), spider mite-eating lady beetles (Stethorus spp.), and aphid-eating syrphid flies. By getting higher numbers of natural enemies into the fields earlier than might otherwise have been the case, pests like spider mites were kept under biological control all season long. Leafhopper numbers were also lower, leading James to suspect that parasitic wasp species attacking this pest were also boosted by wintergreen oil.

This is the basis for commercial products such as PredaLure, sold by Rincon-Vitova Insectaries and others to maximize natural enemies providing biological pest control. Plants are virtual chatterboxes of chemical communication, and wintergreen oil and methyl salicylate are just the tip of the iceberg in terms of natural compounds awaiting field testing. Farnesene, caryophyllene and the male-produced lacewing aggregation pheromone iridodial are among the other green lacewing attractants attracting research attention.

When attacked by insects, spider mites, and pathogens (e.g. viruses, bacteria, fungi) or under environmental stress (e.g. chilling, drought, salinity), plants can ooze chemical exudates from their roots into the soil and waft a variety of communication chemicals into the wind. Thereby neutralizing pathogenic soil microbes, luring in pest-eating natural enemies and tipping off downwind neighbors in the plant community to ramp up their immune response in preparation for impending pest attacks.

We have only scratched the surface of what exists and what is possible to develop for biological insect control.

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.