In Haiti, untreated human waste contaminating urban areas and water sources has led to widespread waterborne illness. Sustainable Organic Integrated Livelihoods (SOIL) has been working to turn human waste into a resource for nutrient management by turning solid waste into compost. Read more…
Estimating the relative humidity in soil? Most people do it wrong…every time. Dr. Gaylon S. Campbell shares a lesson on how to correctly estimate soil relative humidity from his new book, Soil Physics with Python, which he recently co-authored with Dr. Marco Bittelli. Read more.…
“How many soil moisture sensors do I need?” is a question that we get from time to time. Fortunately, this is a topic that has received substantial attention by the research community over the past several years. So, we decided to consult the recent literature for insights. Here is what we learned.
Globally, the number one reason for data loggers to fail is flooding. Yet, scientists continue to try to find ways to bury their data loggers to avoid constantly removing them for cultivation, spraying, and harvest. Chris Chambers, head of Sales and Support at Decagon Devices always advises against it. Read more…
We asked scientist, Dr. Gaylon S. Campbell, which scientific idea he thinks impedes progress. Here’s what he had to say about the standards for field capacity and permanent wilting point. Read more…
During a recent semester at Washington State University, a film crew recorded all of the lectures given in the Environmental Biophysics course. The videos from each Environmental Biophysics lecture are posted here for your viewing and educational pleasure. Read more…
Soil moisture sensors belong in the soil. Unless, of course, you are feeling creative, curious, or bored. Then maybe the crazy idea strikes you that if soil moisture sensors measure water content in the soil, why couldn’t they be used to measure water content in a tree? Read more…
We interviewed Gaylon Campbell, Ph.D. about his association with one of the founders of environmental biophysics, Champ Tanner.
Who was Champ Tanner?
Champ Tanner was a dominant scientist in his time and a giant among his colleagues. He was the first soil scientist to be elected a member of the National Academy of Sciences: the highest honor a scientist can achieve in the United States. Some may not realize that throughout a career filled with achievements and awards, he battled the challenges of a debilitating illness. He didn’t let that limit his passion for science, however. His efforts to understand and improve measurements generally went beyond those of his fellow scientists. One of his colleagues once said of him, “Champ’s life exemplified goal-oriented determination and optimism regardless of physical or financial impediment.”
Dr. Tanner was one of the pioneers in applying micrometeorology to agriculture.
What were his scientific contributions?
Champ was an extremely careful experimentalist who was gifted at developing instrumentation. He started out making significant contributions in soil physics such as improved methods for measuring water retention, particle size distribution, air-filled porosity, and permeability. He was one of the pioneers in applying micrometeorology to agriculture and was passionate about finding ways to improve the precision and reliability of measurements. No measurement was too difficult. He designed and built his own precise weighing lysimeters which provided measurements of evapotranspiration in as little as 15 minutes. Later, he switched to plant physiology, reading almost every published paper on the subject and then building his own thermocouple psychrometer and plant pressure chambers, making important contributions in that field.
His largest contribution, however, was the measure of excellence he inspired in the students that he trained. I don’t know of anybody, anywhere in the world, that produced a crop of students that has attained the levels that his have. They’ve all made enormous contributions in many different fields. Perhaps it was because he was a pretty hard taskmaster. He expected the students to meet a standard, and the ones that struggled with that had a hard time. In fact, to this day one former student complains, “About once a year, I have a nightmare in which Champ appears.”
I don’t know of anybody, anywhere in the world, that produced a crop of students that has attained the levels that his have.
Champ wanted his students to measure up, but he also cared about them. His fellow scientist, Wilford Gardner, described him this way, “There was a transcendent integrity to his personality that permeated everything he did. He could be blunt, candid and forthright, but he was never lacking in compassion and concern for students, colleagues, and friends.”
What was your association with him?
I had a wonderful relationship with Champ, although I wasn’t one of his students. One of his former students came to WSU as a visiting scientist and told him about what I was working on. As a result, he brought me into his inner circle of associates and played a vital role in the success of my research. This association even extended to my family who were with me on one of my many trips to Madison. Despite my numerous and occasionally unruly progeny, he and his wife welcomed us like long lost relatives and made each of the children feel special. That’s who they were: the most caring and outgoing people.
Champ also had a sense of humor. He used to call me up to have long discussions about science, and because he was two time zones ahead, it would get pretty late for him. We’d be having an intense discussion about experimentation, and all of a sudden he’d stop and say, “Oh, I’d better cut this off, or I’ll get home to a cold supper and a hot wife.”
What kind of a person was he?
If you worked in his lab, you needed to tow the mark. You didn’t leave tools around, and you didn’t mess them up. If you left out a screwdriver, you’d find it on your desk the next morning with a terse note. And if you took the diagonal pliers, cut some hard wire with it and left some nicks, those would be on your desk too. It was a sort of tough love, but he used it to train his students to the highest possible level.
He taught his students to be rigorous in their measurement protocols
He wanted his students to stand up and argue for their point. If you were the kind of person that could stand your ground and put up a good defense, he loved that. Gardner described Champ in this way, “His work hours were legendary. His standards of science and personal integrity were almost unrealistically high. The stories his students now pass on to their students may sound apocryphal to those who did not know Champ. But it was impossible to exaggerate where Champ was concerned.”
What do you think scientists today can learn from him?
What we can learn from Champ Tanner is not to fool ourselves. He thought you should try to come to an answer in a few different ways, to be sure that it really was the answer. He taught his students to be rigorous in their measurement protocols in order to get the noise out of their experiments. He wanted them to dig to the bottom of problems and understand the details. In his mind, you couldn’t be a scientist and rely on somebody else to figure out heat transfer or radiation. He thought you should understand it well enough that you could defend it yourself.
You can read more about Champ Tanner’s life and scientific contributions in this biographical sketch, written for the National Academy of Sciences when he died.
Gaylon Campbell’s first experience with environmental measurement came in the lab of Dr. Sterling Taylor at Utah State University, where he was asked to make water potential measurements in order to understand plant water status. What he learned with Dr. Taylor became the start of four scientific companies and gave Dr. Campbell the tools and the confidence to become one of the world’s foremost authorities on physical measurements in the soil-plant-atmosphere continuum. Here’s what Dr. Campbell had to say about his association with Dr. Taylor:
Who was Sterling Taylor and why is he considered one of the Founders of Environmental Biophysics?
Sterling Taylor was professor of Soil Physics at Utah State University. He did his undergraduate work at what was Utah State Agricultural College, and earned his PhD at Cornell University. He worked on both theoretical and practical problems in soil physics. His practical work focused on research in the area of plant-water relations and irrigation management. Dr. Taylor worked out water potential limits for both maximum and reduced growth rates of crops. The irrigation limits tables that he put together are still used in today’s handbooks. His theoretical contributions were on linked transport and applications of non-equilibrium thermodynamics to soil physics, which he was working on at the time of his death. Dr. W. H. Gardner, a soil physicist of the time, called the amount of work Dr. Taylor and his students did “unparalleled” and noted that attendees at regional conferences often had to carry Taylor’s “weighty reports” home as overweight baggage.
Attendees at regional conferences often had to carry Taylor’s “weighty reports” home as overweight baggage.
What was your association with him, and how did he influence your life and your science?
Sterling was a kind of second father to me and to many other young scientists. He loved to help boys and teach them what their potential was. At that age, I didn’t have any idea that I could do anything in science. The first assignment he gave me was to set up an experiment to measure the simultaneous movement of salt and water in soil. I had no idea what I was doing, and it was a challenging project. It would be challenging for me to do it right now! But he’d give me ideas about how to do the next thing, I’d try to do it, and eventually I got some data that he thought was useful. He did some analysis of it, and that’s how I learned to measure electrical conductivity and salt concentration in water and soil. Sterling’s lab is also where my brother Eric and I learned how to make thermocouple psychrometers and other instruments for environmental measurements. Those insights led directly to the start of Wescor and Decagon. Campbell Scientific, Juniper systems and others eventually came from those beginnings.
Dr. Taylor was also a very patient man. He made a precision constant temperature bath out of an old washing machine. It had an agitator in the middle to stir the water while cooling it with coils around the outside of the tub. It was a wonderful setup, and he took a lot of pride in how well it worked. He came into the lab one day while I was making some modifications to it. I was drilling a hole through the outer jacket around the Freon(™) coils where the refrigerant ran. He said, “Now be careful if you’re drilling holes through that thing so you don’t hit the coils”. And I said, “Yes, I’m being careful.” But I wasn’t. The coils were a couple of inches apart, and I thought, There’s no way I’m going to hit one. I didn’t even get a ruler. I just eyeballed it, drilled a hole, and hit the tube dead on. I couldn’t have hit it more perfectly if I’d measured as carefully as I could. All the refrigerant came hissing out, and I thought he would hear it over in his office. He probably did hear it, but he didn’t come out to see what was going on. One of the hardest things I ever did in my life was to go in and tell him I’d drilled a hole in his refrigerant tube. He just said, “Well…I guess we’ll have to get some new refrigerant.” He was just patient, and knew how to work with young people.
I made a career choice to be a teacher and have students.
But that wasn’t the only way he influenced me. As it came time for graduation he gave me some advice that had an enormous impact. Once when I was trying to choose between soil physics and medical biophysics he said “do you want to be a little duck in a big puddle or a big duck in a little puddle?” I decided on the little puddle. On another occasion, I was wondering what kind of soil physics position would be best. One of his former students had gotten a job at an experiment station near Kimberly, Idaho, and I thought that would be ideal. He observed, “Those can be fun jobs, but if you go to a position like that you just don’t have any offspring.” That resonated with me, and I thought, “I would like to have offspring.” So I made a career choice to be a teacher and have students. It was wonderful to have had that kind of advice at that critical time.
What do you think we missed because he died so early?
It’s interesting to think about scientific contributions and other types of contributions people make. One of my sons gave me a book of science cartoons, and one of those cartoons shows a couple of scientists talking together. One of the scientists says to the other, “Isn’t it sad to think that everything we come up with now will be disproved in 20 years?”
It just shows you what a transient thing our work is. We think it’s so important, but the important contributions that Sterling made were the numbers of people that he influenced so profoundly. I’m not the only one he was a second father to. Sterling Taylor had a huge family of students. Many went on to prestigious institutions like CalTech (California Institute of Technology), making important contributions over their careers. And they trace it back to Sterling’s influence on them.
How can scientists today emulate the great man that he was?
I think it would be to not take science so seriously but to take interactions with their fellow travelers seriously. There is a quote by Clayton Christensen from an article in Harvard Business Review on how to emulate what Sterling Taylor was. Christensen says, “I’ve concluded that the metric by which God will assess my life isn’t dollars but the individual people whose lives I’ve touched. I think that’s the way it will work for us all. Don’t worry about the level of individual prominence you have achieved; worry about the individuals you have helped become better people. This is my final recommendation: Think about the metric by which your life will be judged, and make a resolution to live every day so that in the end, your life will be judged a success.”
We interviewed Gaylon Campbell, Ph.D. about his association with one of the fathers of environmental biophysics, John Monteith.
John Lennox Monteith, image:agrometeorology.org
Who was John Monteith?
John Monteith was a professor at the University of Nottingham in England and one of the founders of modern environmental biophysics. He pioneered the application of physical principles in the study of how plants and animals interact with their immediate environment. He started his career at Rothamsted Experimental Station in Harpenden, England and was hired as professor at Nottingham in the early 1970’s. He went on to spend time at the International Crops Research Institute for Semi-Arid Tropics (ICRISAT) in India. He published a textbook that has been a foundation for Environmental Biophysics, called Principles of Environmental Physics. He was elected a member of the Royal Society of London, which is the highest scientific distinction a person can receive in the UK. He was also a member of the Royal Meteorological Society and was its president in 1978. These societies are both sponsored by the crown, and he told me on the occasion that he was installed as the president of the Royal Meteorological Society, the queen attended and he sat by her at dinner. He is known for the Penman-Monteith equation that has become the basis for guidelines for estimating irrigation water requirements used by the FAO (Food and Agriculture Organization of the United Nations).
How did you meet him?
As an undergraduate, I knew of John because I worked for a professor at Utah State University (Sterling Taylor), who was measuring water potential in soil using thermocouple psychrometers. I was keenly interested in the subject, so Dr. Taylor gave me a paper on thermocouple psychrometers to read, published in 1958 by Monteith and Owen, written while John was at Rothamsted. John’s work there was influential in developing instrumentation which formed the foundation for Wescor, METER, and several other companies.
When Prof. Monteith’s book came out, it was pretty exciting for me, because it had everything in it that I was trying to teach as a professor of Soil Science. I wrote to John in 1977 inquiring about the possibility of doing a sabbatical there, and he wrote back immediately and arranged for us to come. Amazingly, he and his technician met our big family at Heathrow airport and loaded up the whole crew, including our many duffel bags, into a university minibus. A couple of our bags were missing, and John picked them up from the railway station in Nottingham and delivered them to us the next day. I have often marveled that such a busy and important man would take the time to care for us like that.
A sunflower field in Karnataka, India
What was he like as a colleague?
He was a humble man in a lot of ways. After he passed away, one of his colleagues wrote in and told about some of the experiences he’d had with John in India. India has a pretty hierarchical society, and it’s not uncommon for somebody who is in a position of authority to take advantage of that. John was in charge of one of the big groups within ICRISAT, and the thing that impressed his colleague was that whoever came into John’s office was treated with great respect, whether it was the cleaning person or the lab technician. If they had come to see him, they got the same treatment and the same respect that the director of the lab got.
We worked on a lot of projects together, but the proposal we submitted that was funded was one on improving thermocouple psychometry. I wrote up the paper, but he had written the proposal and provided the funding for the work. I put him down as an author on the paper, and when I got ready to submit it, he went over the paper just as if he were an author and then crossed his name out. He said he hadn’t contributed enough. Well, he contributed way more than most authors do, but he had a set of standards that he expected himself to meet and his contributions to that paper hadn’t met those standards. He was pretty amazing that way.
How did he get to be a part of the Penman-Monteith Equation?
Penman was head of the research group at Rothamsted Experimental Station which Monteith joined, following graduation. Penman was already an established researcher by the time Monteith got there, and the Penman equation was already well known. But, Monteith worked with that equation, and in my opinion, improved it substantially. He never wanted to take credit for that. He always claimed that Penman already understood the things he had added, and he never did call it a Penman-Monteith equation, always referring to it as the Penman equation. But I have never read things of Penman’s that indicated that he had anywhere near the depth of understanding of the equation that Monteith had. To my way of thinking, it’s completely appropriate that his name is associated with it.
What was John’s secret to accomplishing all he did, and how can scientists today emulate his meaningful career?
His gift was the gift of clear thinking. I gave a talk about him a while ago entitled “Try a Straight Line First.” John hated the complexity of modern computer models for crop growth because he couldn’t easily see the end from the beginning in those models. He had the ability to look at a problem, no matter how complex, and just reach in and grab the essence of that problem and show it to you. He used to talk about Occam’s Razor and not multiplying complexity. Einstein was supposed to have said, “Everything should be as simple as possible, but not simpler.” John was always able to find a simple way to look at problems. It may have been a complex process to get there, but once he was done, you had something that you could manipulate. I think simplicity and uncluttered thinking would be the thing to emulate.
