Digging In: David Lindbo
This interview is part of "Digging In," an Agrilinks interview series featuring original conversations and unique perspectives from soil experts. Through these discussions, we explore questions about soil science and management, scaling best practices, and more. Read more from "Digging In" here.
For this interview, we spoke with Dr. David Lindbo. David is a professor in the Department of Soil Science at North Carolina State University and specializes in soil-environment relations. He is also leading the Soil Science Society of America’s International Year of Soil Taskforce and is the head of the Education Strategic Planning Work Group of the Soil Renaissance Consortium.
When we spoke to David, he emphasized the importance of utilizing different soil management practices as they are most appropriate based on context, taking into consideraton regional and climatic differences as well as governance. He also listed a number of organizations he has worked with in order to promote soil science and educational outreach.
Agrilinks: From your perspective, how is the approach to soil science and soil management changing in agricultural development?
David: It’s taking a look at a more holistic approach, and trying to integrate what we know about what plants need in terms of nutrients with what the soil needs in terms of management. We need to make sure our management processes incorporate both plant needs (with fertilizer) and soil needs (with organic matter content), and look at biodiversity and see how critical that is for a healthy soil ecosystem. I think that one of the big moves in the last 20-30 years has been the idea of going from full tillage to conservation tillage to no-till, and trying to improve soil structure, organic matter content, and water retention in soils. No-till doesn’t work everywhere, and management practices vary, so the next step is to figure out what works best in each region based on each region’s soil. Soil health is also most recently one of the key initiatives coming out of the Natural Resources Conservation Service (NRCS), Soil Renaissance, and the Soil Science Society of America (SSSA). This, again, takes a more holistic view of the soil.
Agrilinks: Specifically, what are the top two critical issues that you think need to be addressed in soil management?
David: The first is that we need to improve general understanding of soil. I sometimes like to say that we need an increased understanding that “you don’t treat soil like dirt”. It’s a living, breathing entity, and not a renewable resource, and I think that it is key to understand that once you’ve lost soil, it is gone. You need to manage it and get the fertility to where it needs to be for the crop that you’re growing, and you need to make sure that the crop is appropriate to the soil. For example, irrigation needs differ based on each crop and soil type. We need to manage for eco-regions, which are going to be different across the world. What we do in the mid-west won’t work in sub-Saharan Africa. The second issue is learning to choose the management schemes that work best for where you are, including which crop is most appropriate to be growing.
Agrilinks: What do you view as the highest potential risk of poor soil management in the next decade?
David: That is probably something that is again regional. For example, I’m in North Carolina, so salinization and desertification are not much of a risk here. But in other parts of the world, they are a huge risk. You need to look at soil management locally and understand what the risks are based on this context. Soil degradation in general covers a lot of issues, including erosion, loss of organic matter and more, and those are key parts. But also, if you are irrigating, you need to irrigate appropriately so that you’re balancing between the soil and the water resource, because in some regions, water isn’t a renewable resource either. I like to think of the big picture, but then relate it to the little picture, and soil management issues vary across different scales.
Agrilinks: In your opinion, what are the keys to scaling up adoption of successful and improved soil management practices?
David: Again, it’s going to vary. In areas where you have a population and a government that is stable, you can accomplish a lot more. Local and regional politics play a role. In my case, as a post-doctoral researcher, I was trying to work with dairy farmers to help them realize that by managing their manure better, they wouldn’t need to put as much fertilizer down. We used an economics lens; we didn’t come from the environmental or ease of application standpoint, but showed through economics how over-application affected what they were doing, and that by over-fertilizing you’re wasting money. Best management practices using an economic lens sometimes work very well in stable environments. In other areas, a lot of adoption won’t occur until you have a stable government where people are fed and aren’t existing in subsistence mode. When people can grow a crop and have a stable market to bring it to, they have a better idea of how to make money on what they’re growing and improve their practices for next year. If you don’t have this, people may grow cash crops in order to try to make the most profit, and they might not take as long-term of a view about what may be best for their soil and their farm. The politics can really play as much of a role as the training. But from a training perspective, local knowledge is so valuable. Farmers trust those they know, so you need to train key people within a locality—“train the trainers”—to improve farmer outreach.
Agrilinks: For you personally, what led you to pursue your interest in soils and soil science?
David: My grandfather on my mother’s side had a small farm outside Boston and I started working with him in the third grade. He had a few cows and chickens and we sold the excess we had to the Boston Market. My father also had an agriculture background; he grew up on a wheat farm in North Dakota and Oregon—very different from the northeast. My family has always had some type of farming being done on both sides of the family. So I came from that background, and it was interesting to do.
What finally pushed me into this field, though, was a soils professor I had at University of New Hampshire, who taught in a different manner than any person I had seen. He never wrote on the blackboard, he just used slide projectors and an overhead, and had a musical script that went with everything. Some people didn’t get him, but for me he made soils exciting. In one of the lectures toward the end of the course I had with him, he started by saying, “Thanks for coming to this class. This is the most important class you’ll ever take, because without soil you wouldn’t be here.” He proceeded to teach us how everything you touch comes from soil. Soil becomes one of the four things you can’t live without: sunlight, water, air and soil. All of your food, clothing, and shelter comes from soil. Many people have pointed out that you would be "hungry, homeless, and naked" without the soil. Hearing that when you’re an impressionable college student—that is what pushed me over.
Agrilinks: Can you tell us a bit more about Soil Renaissance and your work there?
David: What I’m doing there is I’m working with the Consortium to help populate resources and work with their soil education group. Right now we are speaking with the three other groups [Measurement, Economics and Research] to come up with their programs so that we can take that information and develop materials related to that. There’s a lot already out there by NRCS and SSSA on soil health that is great, so we’re not trying to reinvent the wheel. We want to use and promote that information, and once Soil Renaissance moves forward with specific research needs and information on how soil health improves your economics, we will promote that forward. And it’s been pretty exciting working with the Farm Foundation and the Samuel Roberts Noble Foundation, because they have the same objectives.
Agrilinks: What work are you doing in your lab, or through extension services, that you are most excited about?
David: I do a lot with wastewater, and teach courses on septic systems and septic systems management, which primarily applies to practitioners already out in the field, and I think that is interesting. But what I like best right now is working with kids. I do a lot of K-12 educational outreach now, including giving individual lectures on soil throughout North Carolina to students in third grade and above. I also coach several teams and work extensively with Envirothon. I train both students and other coaches on soils. I work throughout North Carolina, and one of my student teams last year came in first in the state. A long-term goal is to incorporate a soils module in the Science Olympiad curricula, as I also am involved there. I also work a bit with FFA.
Agrilinks: Can you suggest three key resources about soils that practitioners can refer to for additional information?
- The SSSA website for K-12 education, which has links to other sites, including an “Ask a Soil Scientist” feature.
- The SSSA website dedicated to IYS.
- The NRCS soil health website.
Additionally, I would recommend just going to your local cooperative extension office for more localized information. This, of course, can be tougher overseas, but if you know your climate and have internet access, you can look up information about a state in the U.S. that’s similar and take advantage of those resources.
Dr. David Lindbo is a professor in the Department of Soil Science, specializing in soil-environment relations, at North Carolina State University. He is also leading the Soil Science Society of America’s International Year of Soil Taskforce, and is the head of the Education Strategic Planning Work Group of the Soil Renaissance Consortium.
His research and extension programs at NCSU focus on non-agricultural land use and management of soils, with primary interest in correlating soil morphologic and physical properties to environmental conditions. All of these areas involve a holistic soil/environmental approach to research. Additional interests of Dr. Lindbo include soil and landscape relations.