Nansen, an associate professor in the UC Davis Department of Entomology and Nematology, published his observations in a recent edition of PLOS ONE, the Public Library of Science's peer-reviewed, open-access journal. He researches the discipline of remote sensing technology, which he describes as “crucial to studying insect behavior and physiology, as well as management of agricultural systems.”
Nansen demonstrated that several factors greatly influence the reflectance data acquired from an object. “The reflected energy from an object--how it looks-- is a complex cocktail of energy being scattered off the object's surface in many directions and of energy penetrating into the object before being reflected,” Nansen pointed out. “Because of scattering of light, the appearance--or more accurately the reflectance profile--of an object depends on what is next to it! And because of penetration, the appearance of an object may also be influenced by what is behind it!”
“We don't think of us humans having x-ray vision, but part of what we see is actually reflectance from layers/tissues below the surface,” Nansen related. “Like the fairy tale about how a true princess can feel a pea underneath many mattresses, penetration of light affects what we consider surface reflectance. This is easily demonstrated by placing a white sheet of paper on top of a paper with colored dots--even with a few sheets of white paper on top of the dots, it is still possible to see the colored dots--so some level of penetration is detectable by the human eye. But advanced cameras are much more sensitive to penetration than the human eye.”
Biomedical researchers “take great advantage of penetration--the ability of radiometric energy to penetrate into soft human tissues, such as the brain, liver, lung, skin--to characterize the function or structure of tissues as part of disease diagnosis and image-guided surgery,” Nansen said. “But in non-medical classifications of objects, penetration and scattering represent a challenge, because these optical phenomena can lead to unexpected ‘noise' in the reflectance data and therefore reduced performance of reflectance based classifications of objects.”
“The findings are of considerable relevance to research into development of remote sensing technologies, machine vision, and/or optical sorting systems as tools to classify/distinguish insects, seeds, plants, pharmaceutical products, and food items.”
In the PLOS ONE article, titled “Penetration and Scattering—Two Optical Phenomena to Consider When Applying Proximal Remote Sensing Technologies to Object Classifications,” Nansen defines proximal remote sensing as “acquisition and classification of reflectance or transmittance signals with an imaging sensor mounted within a short distance (under 1m and typically much less) from target objects.”
In recent years, Nansen has shown that reflectance profiling of objects can be used to differentiate viable and non-viable seeds; insects expressing terminal stress imposed by killing agents; developmental stages of fly pupae; and insect species in a cryptic complex.
“Even though the objects may look very similar--that is, indistinguishable--to the human eye, there are minute/subtle differences in reflectance in some spectral bands, “ Nansen said, “and these differences can be detected and used to classify objects.”
With this newly published study, Nansen has demonstrated experimentally that imaging conditions need to be carefully controlled and standardized. Otherwise, he said, “penetration and scattering can negatively affect the quality of reflectance data, and therefore, the potential of remote sensing technologies, machine vision, and/or optical sorting systems as tools to classify objects. “
Nansen described the rapidly growing number of studies describing applications of proximal remote sensing as “largely driven by the technology becoming progressively more robust, cost-effective, and also user-friendly.”
“The latter,” he wrote, “means that scientists who come from a wide range of academic backgrounds become involved in applied proximal remote sensing applications without necessarily having the theoretical knowledge to appreciate the complexity and importance of phenomena associated with optical physics; the author of this article falls squarely in that category!”
“Sometimes experimental research unravels limitations and challenges associated with the methods or technologies we use and thought we were so-called experts on,” Nansen commented.
Nansen, who specializes in insect ecology, integrated pest management, and remote sensing, joined the UC Davis faculty in 2014 after holding faculty positions at Texas A&M, Texas Tech and most recently, the University of Western Australia.
Dr. Godfrey was internationally acclaimed for his research on rice and cotton. He was heavily involved in developing IPM to maintain the sustainability of California agriculture, seeking “to reduce the ‘footprint' of agriculture on the environment and society, and to advance the science of entomology and applied insect ecology.”
At UC Davis, he taught arthropod pest management and agricultural entomology. He developed IPM strategies for not only rice and cotton but for such field and vegetable crops as alfalfa, dry beans, timothy grass, melons, mint and onions.
A member of the entomology department since April 1991, Dr. Godfrey served as its vice chair in 2008, and also that year, as president of the Pacific Branch, Entomological Society of America.
“Larry was an outstanding contributor to the department, not only as a researcher and teacher, but also in the effective ways that he connected with clientele through outreach,” said Steve Nadler, professor and chair of the UC Davis Department of Entomology and Nematology. “He was a member of our department's Executive Committee and I could always count on Larry for sound advice.”
“Being the two Davis faculty with agricultural entomology extension duties, Larry and I shared a lot over the last 25 years and he was my closest colleague in our department when he passed today,” said Extension entomologist and distinguished professor Frank Zalom, an IPM specialist and a past president of the Entomological Society of America. “I've always respected him for being quiet and humble despite his many accomplishments. He filled the shoes of several faculty members who retired before he came to Davis and he did his job exceptionally well. It's hard for me to imagine not having him nearby as the go-to entomologist for field crops, although his research, extension, and, most importantly his graduate students, will serve as his legacy for years to come.”
Said professor Jay Rosenheim: “Larry was a researcher who always placed the farmer's needs first. This is why he was so highly valued by California's growers of rice, alfalfa, cotton, and vegetable crops, and why his research program grew and grew over his years at Davis. He was also an excellent communicator, and epitomized the role of researcher/educator in the Land-Grant system. Despite his illness, he continued to work tirelessly on his pest management research, refusing to compromise on his commitments. His dedication to our profession was truly remarkable.”
Yolo County Farm Advisor Rachael Long, who collaborated with Dr. Godfrey on dry bean research, said: “He was an incredibly dedicated field crop entomologist and terrific colleague with team spirit, and his loss leaves a big hole in our lives and I'll miss him.”
“What I admired about Larry was his stoicism,” said former graduate student Mohammad-Amir Aghaee, now a postdoctoral fellow at North Carolina State University. “Nothing seemed to wear down his resolve.”
Dr. Godfrey, born July 7, 1956, grew up on an Indiana farm, and was a 1974 graduate of Salem (Ind.) High School. He received two entomology degrees from Purdue University, West Layfayette: his bachelor's degree in 1978 and his master's degree in 1980. He earned his doctorate in entomology in 1984 from the University of Kentucky, Lexington, studying with major professor Kenneth Yeargan. He was a member of Phi Beta Kappa, Phi Kappa Phi, Sigma Xi and Gamma Sigma Delta.
Said Yeargan: "As I stated in my letter of recommendation for Larry many years ago when he applied for the position at UC Davis, Larry was an outstanding 'synthesizer' of information. He had a knack for looking at a problem, thinking through all the ramifications, and coming up with logical, practical ways to approach the problem – and usually finding a solution. He will be missed by many." It was at the University of Kentucky where Larry met his wife-to-be, Kris Elvin, then a postdoctoral scholar.
Dr. Godfrey began his career as a product development specialist for Union Carbide Agricultural Products Co., Inc., Research Triangle, N.C., before joining the University of Nebraska's Department of Entomology from July 1987 to March 1991 as a research associate.
“Growing up on a farm in Indiana, I saw first-hand the ‘battles' that farmers and homeowners face trying to produce crops and grow landscape plants in competition with insects,” Dr. Godfrey recalled in an earlier interview. “I became fascinated with insects through the typical ‘bug-in-a-jar' hobby. A county Natural Resources Field Day cultivated my interest in entomology and this led to enrollment in the 4-H entomology project. By the time I was several years into the 4-H project, I was transporting a dozen wooden collection boxes full of pinned insects to the county fair.”
“My first summer job involved surveying for Japanese beetles as they progressed across Indiana. This was an invasive insect in the Midwest in the mid-1970s; this same insect is of serious concern now in California an invasive pest that could damage many crops—such as grapes—and ornamentals—such as roses.”
Dr. Godfrey was one of 24 founding members of the California Invasive Species Advisory Committee, appointed by then Secretary A.G. Kawamura of the California Department of Food and Agriculture, to recommend “ways to mitigate non-native species' effects on resources throughout the state.” The goal: to protect California's environment, food systems, human health and economy from invasive and destructive pests, plants and diseases.
At UC Davis, Dr. Godfrey zeroed in on invasive insect and mite pests such as silverleaf whitefly, panicle rice mite, and rice water weevil. In addition, he targeted scores of pests, including alfalfa weevils, blue alfalfa aphids, spotted cucumber beetles, and two-spotted spider mites. He researched plant response to insect injury, refining economic thresholds.He also researched various pest management tactics, including biological control, reduced risk insecticides, mating disruption, cultural control, and host plant resistance.
Highly respected by his peers, Dr. Godfrey received the Excellence in IPM Award in 2005 from the Pacific Branch, Entomological Society of America (PBESA), followed by the PBESA Distinguished Achievement Award in Extension in 2010. Nationally, he was elected chair of ESA's Section F (crop protection) in 2002.
For many years, he served as the advisor to the UC Davis Linnaean Games teams, which won regional (PBESA) and national (ESA) championships in college-bowl type competitions involving insect questions. He himself was on the championship 1983 University of Kentucky team, the second annual Linnaean Games in the North Central Branch of ESA “where it all started,” he said. “It was a few years before the other branches started this competition and several years before they did it at the national meeting.”
As part of his Extension work, Dr. Godfrey wrote publications, regularly met with growers, and delivered scientific talks at workshops. He addressed the annual California Rice Field Day for 25 years and also spoke at alfalfa IPM workshops, among others. He was a subject editor for the Journal of Cotton Science and the Journal of Integrated Pest Management. In addition, Dr. Godfrey served on many departmental, college and UC Agriculture and Natural Resources committees.
Funeral services will be held Saturday, April 29 in Salem, Ind., where he grew up. In lieu of flowers, the family asks for donations to pet rescue groups or groups that support young people interested in entomology or agriculture. A memorial and celebration of his life will take place at UC Davis in the near future.
He is survived by his wife, Kris Godfrey; his mother, Laura Godfrey; and sister, Carol Green and family. He was preceded in death by his father, Don Godfrey.
Noted integrated pest management specialist (IPM) Frank Zalom, distinguished professor of entomology, UC Davis Department of Entomology and Nematology, recently received the Perry Adkisson Distinguished Speaker Award from Texas A&M University, College Station, and presented a seminar on “Invasive Species, Integrated Pest Management, and One Perspective from the West Coast.”
Zalom said it was a great honor to receive the award. "Perry Lee Adkisson is among the icons of integrated pest management (IPM)," he said, "and one of the people that I have most looked up to since starting my career in entomology."
Adkisson, chancellor emeritus of the Texas A&M University System and a distinguished professor, now emeritus, at Texas A&M, was the first-ever recipient of all three of the world's major prizes in agriculture: the Alexander von Humboldt Award, the Wolf Prize, and the World Food Prize. He and colleague Ray Smith are credited with developing integrated pest management (IPM).
Both Zalom and Adkisson are past presidents of the Entomological Society of America (ESA) and both are fellows.
Zalom, who holds a doctorate in entomology from UC Davis, joined the UC Davis faculty in 1980 as the Extension IPM coordinator for the UC Statewide Integrated Pest Management Program (UC IPM) and then served as the UC IPM director for 16 years before returning to the Department of Entomology in 2002.
Known nationally and globally for his IPM leadership, Zalom co-chaired the Association of Public and Land Grant Universities' National IPM Committee (NIPMCC) from 1999-2015. He also has served as an IPM representative to the Experiment Station Committee on Organization and Policy (ESCOP) Science and Technology Committee since 2003, USDA Western Region IPM Competitive Grants program manager for 10 years, and on the United States Agency for International Development (USAID) Board of Directors for the IPM CRSP (Collaborative Research Support Programs) from 2001-2005.
Zalom organized and co-chaired--with presidents of four other entomological societies--the first ever International Entomology Leadership Summit, spanning two days within the 2016 International Congress of Entomology (ICE) meeting in September in Orlando, Fla.
Highly honored by his peers, Zalom is an elected fellow of four scientific organizations: ESA, American Association for the Advancement of Science, Royal Entomological Society (London) and the California Academy of Sciences. He is a past president of the Pacific Branch of ESA. He continues to serve as a member of the Entomological Foundation's Board of Directors and the ESA's Science Policy Committee.
Some of his most recent honors: the Entomological Foundation IPM Team Award, the Entomological Foundation Excellence in IPM Award, and the Outstanding Mentor Award from the UC Davis Consortium for Women and Research. He served as the department's vice chair from 2005-08.
Zalom has authored more than 335 peer-reviewed journal articles, book chapters, and books, and has served as major professor for 12 Ph.D. students and seven master's students.
"Dr. Ehler had a remarkable career at UC Davis,” said Steve Nadler, professor and chair of the UC Davis Department of Entomology and Nematology. “In his research he built upon fundamental investigations in integrated pest management (IPM) to provide practical biological control for many different systems. Les was both a national leader in the discipline of biological control, and an outstanding citizen of the department and university.”
Dr. Ehler, who joined the UC Davis Department of Entomology in 1973 and retired in January 2008, was the first biological control specialist on campus and was known as the “quintessential biological control researcher.”
For four decades he championed the use of natural enemies to control agricultural pests and warned of the dangers of pesticides.
Dr. Ehler co-edited the 1990 book, Critical Issues in Biological Control and served four years as president and four years as past president of the International Organization for Biological Control. He also chaired the Entomological Society of America's Biological Control Section.
At UC Davis, Dr. Ehler battled pests such as obscure scale and aphids on oaks, stink bugs on tomato, aphids on sugar beet and white fir, and beet armyworm on alfalfa and sugar beet. His expertise ranges from the theory and practice of biological control to the ecology and management of insects and mites in natural, agricultural and urban environments.
“Les was a meticulous researcher and an excellent applied field ecologist,” said colleague and close friend Extension entomologist Larry Godfrey of the UC Davis Department of Entomology and Entomology. “When he took on a research project, you were confident the project would be conducted well and all aspects of the system considered. He made major contributions to our understanding of stink bug ecology and biological control of stink bugs. Les was also excellent at transferring his knowledge via classroom teaching.”
In the late 1990s, Dr. Ehler discovered that pill bugs, also known as roly-poly bugs, prey on the eggs of stink bugs. Up to then, most entomologists classified pill bugs as strictly vegetarians. Stink bugs, major agricultural pests, suck the juices from legume and brassica seeds and fruit of other crops.
In the early 1980s, Dr. Ehler led the Davis team that documented the environmental impact of malathion-bait sprays used to eradicate the Mediterranean fruit fly. The organophosphate was credited with killing the medfly, but also beneficial insects such as honey bees, and natural enemies of various insect pests.
In one study, Dr. Ehler assessed the non-target effects of malathion in the Bay Area. His studies in Woodside, a San Mateo County community on the San Francisco Peninsula, revealed that populations of a native gall midge exploded 90 times the normal level. Ehler compared the gall midge population in Woodside -- where planes sprayed up to 24 malathion applications -- to the untouched Jasper Ridge Biological Preserve near Stanford University. The gall midge is a gnatlike insect pest that lays its eggs in plants; the burrowing larvae form galls.
Dr. Ehler also helped organic farmers solve problems. He designed a stink bug management program for Yolo County organic farmer Robert Ramming of Pacific Star Gardens after learning of the stink bug invasion in his tomato fields.
“The stink bugs were overwintering in his backyard and in the spring, emerging to dine on mustard and then tomatoes,” Dr. Ehler noted in the feature story. “Stink bugs don't seem to prefer tomatoes — they like mustard and wild radish — but when these hosts were plowed under and no longer available, the bugs went for the tomatoes.” Solution: Don't cut the mustard. Plow it under only when the stink bugs aren't a threat to the tomatoes — that is, before they develop wings and disperse.
Quotes from the January 2008 feature story:
- Yolo County organic farmer Robert Ramming of Pacific Star Gardens: “Les determined what stink bugs prefer, their habitat and where they were overwintering. “We planted a five-foot strip of ‘trap' or ‘bribe' crops (mustard and wild radish) around the tomato fields and got rid of 90 percent of the stink bugs.”
- Rachael Long, a UC Cooperative Extension farm advisor in Yolo, Solano, Sacramento counties: “I greatly admire Les for his contributions to IPM that have helped us better understand the biology of some of our major agricultural pests and how to manage them. Les is one of those extraordinary field researchers with a broad knowledge of entomology that make him a great resource for information. In collaborating with Les on various projects I have a much better understanding on how landscapes impact IPM in cropping systems which I believe will help conservation efforts and improve pest control in our agricultural systems.”
- Chemical ecologist Walter Leal, then professor and chair of the UC Davis Department of Entomology: “Les began teaching biocontrol classes for our department in 1974, drawing hundreds of students. He was trained in the 1960s by the founders of integrated pest management (IPM) and he advocated biological control methods as an important IPM pest control strategy. His work led to a better understanding of how predators and parasites can control pests without pesticides.”
- Entomologist Michael Parrella, then associate dean of agricultural sciences in the College of Agricultural and Environmental Sciences: “Les was the first faculty member hired in the Department of Entomology to teach and advance the science and practice of biological control. Trained in classical biological control at UC Berkeley, he was the heart and soul of biological control at UC Davis, and worked in many biological systems from tomatoes to urban landscapes. For many years, Les maintained his own USDA-certified quarantine laboratory which allowed him to work with biological control agents from all over the world. He was a meticulous researcher who maintained a ‘hands-on' approach with all the projects done in his laboratory and he trained many students who are now leaders in the field of biological control around the world.”
Emeritus professor Harry Kaya of the UC Davis Department of Entomology and Nematology said of his close friend and colleague:
"Les and I overlapped as graduate students at UC Berkeley and I have known him for over 45 years. We were reunited as faculty members at UC Davis when I joined the department in 1976. Les was the quintessential entomologist specializing in classical biological control. His research was always thorough and complete and others have commented on his many contributions to the discipline. We co-taught a class on biological control for many years; he covered the theory and application of parasitoids and predators and I did the lectures on pathogens. Les made sure that the students understood the basis for the theoretical aspects of biological control and their application in the field. In the laboratory portion of the class, he took the students into the field to show them biological control agents in action and developed a useful pictorial handout for identifying the common parasitoids and predators found in California. Even in retirement, he assisted farmers in dealing with the stink bug problems in tomatoes."
"Les was the most organized person that I know. Everything in his research lab and office and home had a place and was neatly and logically organized," Kaya noted. "A few years before he retired, he had a plan on what he wanted to do and purchased a fishing boat. The first time we went out, it was clearly a case of the blind leading the blind. We lost more fishing gear without getting a single bite. Les did not see this as a setback, but as a learning experience. He went fishing with professional guides, learned from them, and became an excellent fisherman. He not only took me but many others fishing for striped bass in the Delta, salmon and striped bass in the Sacramento River, and trout, bass, and kokanee at Lake Berryessa."
"I have lost a good friend and colleague. I will miss the many entomological and other stories and his sense of humor we shared on our fishing trips."
Born Jan. 6, 1946 in Lubbock County, Texas and reared on a family farm near the small town of Idalou, Les Ehler received his bachelor's degree in entomology from Texas Tech University, and his doctorate in entomology from UC Berkeley. He joined UC Davis in 1973 as an assistant professor, advancing in 1985 to professor of entomology and entomologist in the UC Davis Experiment Station. Dr. Ehler was an avid fisherman and enjoyed fishing, particularly for sturgeon and salmon.
He is survived by his son Brian of Susanville, Calif., and daughter Mary Ehler Yung and husband, Eric, of Sacramento, and granddaughters Emma Yung and Georgiana Grace Yung. He was preceded in death by his parents, brother Joseph, and sister Loretta. He is survived by brothers Eugene (Mary) of Denton, TX, Howard (Rita) of Midland, TX and sisters Jan Chapman (Carl) of Houston, TX and Amy Willingham of Irving, TX. He is also survived by numerous nieces and nephews.
Lewis is recognized as a global leader in using nematodes as biological agents, said nematologist Steve Nadler, professor and chair of the UC Davis Department of Entomology and Nematology.
Lewis will receive the award at PBESA's 100th annual meeting, “Science for the Next Century,” set April 3-6 in Honolulu. PBESA is comprised of 11 western states: Alaska, Arizona, California, Hawaii, Idaho, Montana, Nevada, Oregon, Utah, Washington, Wyoming), parts of Canada and Mexico, and seven U.S. territories.
Lewis is now an applicant for the national IPM award, to be presented by ESA at its September meeting in Orlando, Fla.
IPM specialist Frank Zalom, UC Davis distinguished professor of entomology and a past president of the 7000-member Entomological Society of America, praised “Ed's outstanding contributions to our state, national and global agricultural research.”
“Ed's work involves five of our state's 10 most valued commodities: almonds, a $5.9 billion crop, strawberries, $2.5 billion; walnuts, $1.8 billion; tomatoes, $1.6 billion and pistachios, $1.6 billion (2014 statistics),” said Zalom, a past recipient of the Pacific Branch and national IPM awards. “Also in 2014, California's agricultural exports amounted to $21.59 billion in value. Thus, in many respects, California feeds the world, and Ed's research is integral to controlling insects and nematodes.”
“Dr. Lewis has one of the most diversified research programs that I have known,” Nadler said. “He collaborates regularly with many different constituencies ranging from small startup companies to various commodity boards in order to take information from basic laboratory research and apply it to field situations. What ties together many of these projects is biological control of pest organisms with a focus on sustainability and integrated pest management.”
“Dr. Lewis' lab has been instrumental in using entomopathogenic nematodes (EPNs) to implement biological control of a large variety of insect pests,” Nadler pointed out. “His research with these nematodes has focused on investigating the ecological factors that relate to host-finding, persistence in soil, and their efficacy in field situations.”
In addition to understanding factors that influence nematode success, the Lewis laboratory “has worked to understand how other approaches, such as novel fertilizers, can work in combination to increase plant productivity,” Nadler said.
“Few scientists working with EPNs have designed and implemented such detailed and relevant studies to characterize what happens to nematodes under field conditions,” Nadler noted. “Importantly, use of EPNs to control naval orangeworm is effective and can reduce the need for pesticide applications.”
Research entomologist David Shapiro-Ilan of the USDA's Agricultural Research Service said that Lewis' research has “contributed immensely to the disciplines of entomology and IPM.”
“Dr. Lewis has clearly emerged as a world leader in research and application of entomopathogenic nematodes or EPNs,” said Shapiro-Ilan.
A native of New York, Lewis received his doctorate in entomology in 1991 from Auburn (Ala.) University and then accepted postdoctoral positions at Rutgers University and the University of Maryland. He then moved to Virginia Tech to join the entomology faculty there.
Lewis joined the UC Davis faculty in 2004. He serves as the editor-in-chief of the Elsevier journal Biological Control. He is also known for teaching two highly popular classes at UC Davis: “Behavioral Ecology of Insects” and “Biological Control of Agricultural Pests.”