Agroecology from A to Z

Adventures in Agroecology and Food Systems


Biological soil disinfestation, Deliflor Chrysanten, Maasdijk, The Netherlands

At the 2013 GroSci conference this summer, full name: The International Symposium on Growing Media and Soilless Cultivation, I had a chance to tour the growing operations of some of the major players in the international floriculture world.  The Dutch are definitely not messing around when it comes to floriculture, in fact The Netherlands is the world’s largest exporter of ornamental plants and cut flowers.

At Deliflor Chrysanten, the world’s largest Chrysanthemum breeder, we learned about some of the challenges of growing in field soil under glass. Many greenhouses have cement floors and use soilless media to produce plants in pots, but some leave the soil exposed and use it for cultivation. With continuous cultivation of the same or similar crop on a single patch of soil comes a build up of pathogens, especially fungal pathogens that specialize in infecting that particular crop. Many of these fungal pathogens like Verticillium spp. can form resting structures in the soil that persist for long periods of time. What are your options as a grower in this type of production system?

1) Move the greenhouse to a different patch of soil (OK, not really an option because of the heavy up front investment in the greenhouse and land. High tunnels are designed to be moved…greenhouses, get out of town!)

2) Spray/ fumigate the soils with synthetic chemical fungicides (Effective, but carries an environmental burden)

3) Steam sterilize the soils in situ (Current method of choice, less toxic than fungicides, but carries a high fossil fuel cost and therefore a different kind of environmental burden)

4) Biological soil disinfestation

What is biological soil disinfestation? It is a technique developed separately in Japan and The Netherlands as a biologically based crop disease management strategy. The basic principle is that a carbon based substrate is added to the soil, then the soil is covered with an impermeable layer. Oxygen levels rapidly decrease in the soil as soil microbes consume the feast provided by the added organic matter. Anaerobic microorganisms become active in the soil in the absence of oxygen and contribute to the build up of compounds in the soil that are toxic to the resting structures of fungal plant pathogens (most likely organic acids). The tarp is removed and the soil is allowed to stabilize for a few days before planting while aerobic microbes become active again and the toxic compounds are degraded.

We heard from Henk Meints of Thatchtec who has been carrying out research and development for specialized blends of organic matter for use in soil resetting.


Deliflor Chrysanten greenhouse facilities in Maasdijk, NL
Satellite image from Google Maps

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Chrysanthemum transplants in soil
Photo credit: Paula van Ommen

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Soil covered for soil steaming process, an alternative to fungicide use
Photo credit: Paula van Ommen

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Chrysanthemum breeding plots
Photo credit: Paul van Ommen

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Blooming chrysanthemums
Photo credit: Paula van Ommen

A special thanks to Paula van Ommen for allowing me to use her beautiful photos of these farm tours.


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Regional flour milling, Trumansburg, NY

Back in 2010 when I was living in Ithaca, NY I had the opportunity to tour a local grain mill in Trumansburg, Farmer Ground Flour. The region has a long history of grain milling with an old water powered mill at the top of Lucifer Falls/Enfield Falls in what is now Treman State Park. The water-powered gristmill was built in 1839 by Isaac Rumsey and used to mill wheat and corn until 1917.

Old Mill at Treeman State Park, Source:

Old Mill at Treeman State Park, Source:

And of course the Haudenosaunee (French name: Iroquois) people were grinding corn in the region for many centuries before that, with Jane Mt. Pleasant dating corn’s arrival to North America at 2,000 years ago. There is a regional project to bring back traditional Haudenosaunee white corn in the areas it was historically grown. If you are an agricultural history nut like I am, you will love Jane Mt. Pleasant’s 2011 paper, The paradox of plows and productivity: an agronomic comparison of cereal grain production under Iroquois hoe culture and European plow culture in the seventeenth and eighteenth centuries. Students in my Land Steward’s course read this paper and it sparked some really fascinating discussions on how traditional ecological knowledge can guide modern sustainable agriculture practices. The corn yields in the traditional no-till system were astounding.

Haudenosaunee women grinding corn, unidentified 1664 engraving

Haudenosaunee women grinding corn, unidentified 1664 engraving

During the tour, you’ll see freelance journalist Sharon Tregaskis scribbling notes as we talk with Greg. Shortly after the tour she published a profile of the milling operation in the Cornell Alumni Magazine. I also love her piece on Black Currant production in the Fingerlakes. The winter 2013 issue of Edible Fingerlakes also has a nice profile of Farmer Ground Flour. So as much as I would like to ramble on about this operation, I’ll let Greg Mol, the miller and the professional writers, Sharon Tregaskis and Amy Halloran, take it away…

A brief note about this tour: These were the early days of design, construction and operation at the Farmer Ground Flour Mill. They have an updated facility now, but I feel this video is still instructive especially to those who are just starting out in a regional food processing business. An incredible amount of ingenuity, tinkering and research are involved in getting a project like this up and running because the infrastructure and equipment to support similar enterprises assumes a much larger scale of operation. Check out how this business re-invented small-scale regional milling:

Updates: Farmer Ground Flour received a USDA grant in 2012 supporting their work to create a sustainable regional food system. You can keep up with their progress on their Facebook site.

Farmer Ground Flour Granted Funds by USDA Rural Development to Expand Market (from the NOFA-NY newsletter)
“Farmer Ground Flour was awarded $75,000 by the USDA Rural Development Fund under the Value-added Producers grant program. These funds will be matched by $50,000 in working capital contributed to the project by Farmer Ground Flour, and a $25,000 personal loan made to the project by local residents Jon Bosak and Bethany Schroeder. Mr. Bosak and Ms. Schroeder are enthusiastic about participating in reviving local grain growing and milling in Tompkins County, and agreed to have the interest on the loan paid to them in flour and grain on a monthly basis. The two-year, $150,000 marketing expansion project will focus on expanding wholesale sales to bakers and institutions, and retail sales at stores and farmers markets.”

A brief note in memory of Bethany Schroeder, her work in the sustainability movement in Tompkins County lives on…

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East New York Farms, Brooklyn, NY

When I was living in Ithaca, I was part of a graduate student group called New World Agriculture and Ecology Group (NWAEG). One of NWAEG at Cornell’s members, Megan Gregory, learned about about an innovative urban farming group through her research project in NYC, The Garden Ecology Project. In collaboration with local food justice groups, NWAEG at Cornell (a graduate student group) invited two youth interns and a staff member from East New York (ENY) Farms in Brooklyn to head up state and share the secrets of their success with us in s series of events on urban agriculture and food justice that we called “Urban Harvest”. ENY Farms has recently been profiled in the NY Times and is one great example of what people and communities are rolling up their sleeves and doing while other parts of the food movement are doing a lot of talking according to Erika Nicole Kendall’s recent article in Salon, America’s Food Debates are Just White Men Talking. Also, ENY Farms was also just featured in one of my favorite radio programs, Story Corps, with a series of interviews of urban farmers and food justice advocates in East New York. You can listen to all of the interviews on the ENY Farms YouTube channel.

Central NY’s food justice movement has been growing in recent years through individuals, churches, and non-profits like GreenStar Co-op. The movement has developed partnerships within Cornell University and Cornell Cooperative Extension most notably through the Whole Community Project, Gardens 4 Humanity and Healthy Soils, Healthy Communities. We invited members of these projects to sit on a panel with our visitors from ENY Farms.

The next day, Southside Community Center hosted an all day event, Youth in Urban Agriculture and Community-Led Economic Development, and invited the community to come and hear about ENY Farms’ progress in creating the kind of food system they want to see. Youth interns from ENY Farms and Cornell students and Ithaca community members facilitated a visioning process where the community laid out the desired positive changes in the food system. Fun fact, our neighbor in Ithaca remembered when Eleanore Roosevelt came to town to the opening celebration of the Southside Community Center’s new building in 1938.

Updates: David Vigil is now the Director of ENY Farms, and although the Ithaca community misses her (a lot!) Kirtrina Baxter is doing food system work in Philadelphia.


Kirtrina Baxter, then director of Southside Community Center and Greenstar Community Projects


Cameal, youth intern with ENY Farms facilitating a community visioning session at Ithaca’s Southside Community Center


Musheerah, youth intern at ENY Farms facilitates a community visioning session at Ithaca’s Southside Community Center



Event organizers and guests taking some time to explore Fingerlakes gorges
L to R: Kirtrina, Musheera, David, Cameal, Jahi and Sam.

ENY Farms

It was really fun to host ENY Farms members at our home in Ithaca’s Northside neighborhood. Best potluck ever!

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SAEA 2012 Comparative agroecology at a liberal arts college: Assessing sustainability and comparing US & Chinese farming systems

David Hougen-Eitzman of Carlton College gave this talk at the 2012 Sustainable Agriculture Education Association conference in the session: Transformative food systems programs, coursework and curricula. His students have the amazing opportunity to tour, study and evaluate the sustainability of farming practices in China during a winter field course and compare those farms to others in the US. In the talk, David covers how he organizes the course in terms of small group student projects and the course readings and sustainability assessment tools he uses in the curriculum. I’m excited to incorporate similar sustainability assessment tools into my teaching and really enjoyed hearing about this course.

Carleton College

Carleton College students tour a farm in China
Photo from:

Carleton tea farm

Carleton College students tour a tea farm in China
Photo from:

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SAEA 2012 Gathering Together Farm, Philomath, OR

During the 2012 Sustainable Agriculture Education Association conference, we got to tour a regional farm, Gathering Together Farm in Philomath, OR. Not only do they produce wholesale vegetables, run an on-site farm stand and restaurant, sell at 9 farmers’ markets, run a 350 family CSA, but they also operate a seed business. Join us as we cover topics like organic soil nutrient management in unique soils with naturally high magnesium, how the Willamette Valley became the global hub for vegetable seed production, regionally adapted seed production and season extension.

Many folks, especially those who grew up in urban and suburban areas, haven’t heard of or seen a grange. Does the National Grange of the Order of Patrons of Husbandry ring a bell? No? Years ago, I had the pleasure of being invited to speak at the Live Oak (#503) grange in Santa Cruz, CA by the organization that was funding my research at the time, the Organic Farming Research Foundation. I learned about the history of the populist grange movement and a modern movement to revitalize many of the US’s dying grange halls with a sustainable agriculture twist.

Gift for the grangers / J. Hale Powers & Co. Fraternity & Fine Art Publishers, Cin'ti. ; Strobridge & Co. Lith. Cincinnati, O. Promotional print for Grange members showing scenes of farming and farm life. Source: Wikipedia

Gift for the grangers / J. Hale Powers & Co. Fraternity & Fine Art Publishers, Cin’ti. ; Strobridge & Co. Lith. Cincinnati, O. Promotional print for Grange members showing scenes of farming and farm life. Source: Wikipedia

Back in the Willamette Valley, Mary’s River Grange #685 hosted conference goers for an amazing local food dinner catered by Gathering Together Farms and shared their efforts to organize green granges in Oregon, “The Green Grangers“.

Game hens and eggplant. I don't usually post photos of food, but this meal was so amazing, and to eat it in a Green Grange, was quite a treat!

Game hens and eggplant. I don’t usually post photos of food, but this meal was so amazing, and to eat it in a Green Grange, was quite a treat!

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SAEA 2012 Transformative food systems education in a land-grant college of agriculture: The importance of learner-centered techniques

Ryan Galt from UC Davis gave a talk at the Sustainable Agriculture Education Association (SAEA’s) 2012 conference on the importance of learner-centered inquiries in food systems education. I found a frank discussion on how to motivate and empower students to create positive changes in the food system without completely depressing them very helpful for my teaching. I’m not sure how well I did, though! At the end of each class I taught Fall 2012 I would check in with my students about our reading and discussion for that day and ask them where they were on the scale of empowered/ inspired to depressed/powerless. Apparently most of our readings were pretty depressing. While some issues in the food system can seem insurmountable, it is our challenge as educators to be honest about the current situation while providing tools for students to be constructively involved in creating solutions in line with their academic and personal interests.

Ryan is now a member representative on the SAEA steering council and we’re excited to have him and the other new members involved.

Here are some related publications from Ryan and his SAEA and non-SAEA collaborators.

Transformative food systems education in a land-grant college of agriculture: the importance of learner-centered inquiries

Facilitating competency development in sustainable agriculture and food systems education: a self-assessment approach

Engaging Values in Sustainable Agriculture and Food Systems Education: Toward an Explicitly Values-Based Pedagogical Approach

You might also want to check out the special issue of JAFSCD on higher education and food systems.

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Working windmills in the Dutch food system

Note: Today is the one year birthday of this blog. We’re almost at 5,000 views! A huge thanks to all of the readers out there who share an interest in sustainable food systems. In celebration, I’m starting a series of posts on the European food system documenting my adventures so far living in Wageningen, The Netherlands and working as a visiting postdoctoral researcher at Wageningen University.

This windmill, Molen de Vlijt, holds a special place in my heart, because it is the first windmill I’ve ever seen. I stumbled across it while taking a walk in my new town, Wageningen, this past winter. Built in 1879, the mill has survived lightning strikes, shelling in WWII and decades of neglect before being lovingly restored in 1979. This year happens to be the city of Wageningen’s 750th anniversary. I can’t wait for the special molenmarkt (mill market) this fall celebrating 750 years of milling for bread making.

Molen de Vlijt or "Mill of Diligence"

Molen de Vlijt or “Mill of Diligence”

750 years of milling

750 years of milling

The mill grinds regional organic grains and is open to the public on Saturdays. Being inside the mill while it’s running is almost like a steam punk space ship getting ready for lift off. The feeling of kinetic energy and the tremendous noise of the moving parts as the wind speeds up and slows down is very exciting.  I already knew I had a strong interest in traditional and modern food processing and preservation. I’ve toured Camas Country Mill in Oregon, and the historic Enfield Falls Mill in New York, but my experiences touring this mill have sparked a special interest in traditional wind technologies in the food system. Apparently I’m not alone, because there is an International Molinological Society that I just may have to investigate further. In this video, I take you inside the mill while it’s running from the ground floor to the fourth level. Here is a diagram of the inner workings of the mill as a guide.

Mill diagram from

Mill diagram from

Ready for baking!

Ready for baking!

Is it any wonder the Dutch are leaders in modern wind technology? Neeltje Jans, Zeeland province

Is it any wonder the Dutch are leaders in modern wind technology? Neeltje Jans, Zeeland province. And yes that is my Dad trying to push this wind turbine over into the North Sea!