mkbomford's blog
Storing Food Without a Fridge
Submitted by mkbomford on Fri, 2008-12-05 09:36.Many farms in this part of Kentucky didn't get electricity until the mid-1940s. A few farmers still remember the strategies their families used to store food without freezers or refrigerators.
Times have changed. Kentucky now has some of the cheapest electricity in the country, and we use more of it than most other Americans. Almost all of it comes from coal-fired power plants. As a result, Kentucky releases 4% of the country's greenhouse gasses, but accounts for just 1.3% of the population. Lexington, the nearest urban center to Frankfort, has the largest per capita carbon footprint of the nation's 100 biggest cities.
Kentucky State University hosts an annual conference in November for limited resource and minority farmers. During a lunch break a few of the conference participants ventured out into the cold to guide us in the construction of a traditional sweet potato storage pit. We placed cured sweet potatoes in a well-drained pit on a thick bed of straw. Layers of sweet potatoes were separated by layers of straw, creating a giant lasagna underground. The final layer of straw was covered by a thick layer of soil and a tarp to keep the potatoes from freezing (too cold) or sprouting (too wet). As we worked, some of the farmers reminisced about other strategies their families used to store food without refrigeration.
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We will use thermocouples attached to a datalogger to continuously monitor temperatures at the soil surface and at all layers of the pit. Over the course of the winter we will remove sweet potatoes periodically to compare their storage life to that of sweet potatoes stored in the cool, dry basement where we kept our seed potatoes through the winter last year. Sweet potatoes store best at temperatures in the mid-50s, so the biggest concern with the pit is that the temperature will get too low.
Sweet potato storage pits have been used for centuries in South and Central America, Polynesia, and Africa. The size, shape, and structure of sweet potato storage pits typically used in the American South is very similar to that of pits used in West Africa, suggesting an African origin for the method we used.
Michael Bomford provides research and extension services related to organic agriculture and small-scale renewable energy production through Kentucky State University's Land Grant Program. He thanks John Clay, Harold Benson, Eddie Reed, Hank Schweickart, Brian Geier, John Rodgers, and participants in KSU's Limited Resource and Minority Farmer Conference for their help with building the sweet potato storage pit at the KSU Farm.
Organic disease management in high tunnels: A little piece of the sustainable agriculture puzzle
Submitted by mkbomford on Wed, 2008-11-26 06:26.High tunnels are simple, solar-heated greenhouses. They use much less energy than heated greenhouses.
Winter temperatures are warmer inside a high tunnel than outside, but still much cooler than summer temperatures. High tunnels temper seasonality; they don't eliminate it.
Many of the growers who use high tunnels for winter vegetable production in our region have problems with a disease caused by a fungus that thrives in cool, moist conditions. Over the past three years I have had the pleasure of working with a team of scientists and growers to test methods of controlling the disease that would be compatible with organic agriculture standards.
Michael Bomford provides research and extension services related to organic agriculture and small-scale renewable energy production through Kentucky State University's Land Grant Program. He thanks Paul Vincelli, George Antonious, Paul Wiediger, Alison Wieidger, Brian Geier, Ed Dixon, and John Rodgers for their collaboration on the study described here. Funding was provided by the USDA's Sustainable Agriculture Research and Education (SARE) program.
Hand harvest of sweet potatoes in a biointensive market garden
Submitted by mkbomford on Wed, 2008-11-19 12:03.Connie Lemley operates a 1-acre market garden north of Frankfort, Kentucky. She sells her salad greens at the Frankfort farmers' market.
Connie is very aware of the high energy use typical of conventional farming systems in North America, and works hard to use less energy-intensive production methods. Apart from a small roto-tiller that she has used to break new ground, she farms entirely with hand tools. She has built up soils with a very high organic matter content through repeated fall applications of horse manure. The most energy-intensive part of her system is bringing her produce to market, which she does with a diesel station wagon that runs on french fry grease from local restaurants. Somewhat dissatisfied with the amount of energy needed to get back-and-forth to town, she is considering buying a large lot in Frankfort where she can continue farming within cycling distance of the farmers' market.
Connie has been keeping track of all of the inputs used in her sweet potato production system so that we can compare her real-life biointensive production system to the experimental biointensive plots we have established at the Kentucky State University Research Farm. She planted and harvested her sweet potatoes within a few days of us. I visited her farm on harvest day to collect a little video footage.
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Michael Bomford provides research and extension services related to organic agriculture and small-scale renewable energy production through Kentucky State University's Land Grant Program.
Oil and commodity food prices
Submitted by mkbomford on Fri, 2008-11-14 07:43.Here's a visual to show just how closely the prices of oil and food commodities have been linked recently.
Fuel from food crops
Submitted by mkbomford on Thu, 2008-11-13 15:08.This is perhaps one of the less vigorous indictments of the growing push to make fuel from food crops.
‘Morally inappropriate!’ pronounces Eric Holthusen of Royal Dutch Shell.
‘A crime against humanity!’ says Jean Ziegler of the UN.
‘Crazy!’ says Douglas Casson Couts of the UN World Food Program. ‘Until recently, fuel was oil from the ground and was used to make power or run automobiles, and food was for people. Never the two shall meet…’
Imagine my horror, then, to learn of the evildoings of Dan West, an orchardist from Macon, Missouri, who converts waste fruit into ethanol to power his farm machinery. ‘It’s exciting,’ says the hardened practitioner of this crime against humanity, ‘I also thought it would be nice to be self-sufficient, using our ethanol to power our mower and tractor.’
Mr. West obviously lacks the refined ethical sense of Royal Dutch Shell, the UN’s sense of history and proportion, and the common sense of my lunchtime tablemates.
If you detect a note of sarcasm here, please don’t take it as evidence that I am insensitive to the plight of the world’s hungry. The spike in commodity grain prices this summer caused further insecurity among those already living on the edge of survival, and sparked very justifiable food riots in places like Egypt, Haiti, Bangladesh and Mozambique. America’s corn-to-ethanol program contributed to the spike.
Let me suggest that the true injustice is more complex then the fact that a food crop was used to make fuel. The recipe for disaster had several steps.
Recipe for Disaster
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Lest I be accused of an anti-American rant, let me emphasize that I see the world's wealthy nations as both perpetrator and victim of addiction. While promoting dependence on cheap grain, we have become dependent on cheap fuel. Since we cannot satiate our current demand for non-renewable energy with any combination of renewables we must simultaneously reduce our energy consumption and explore the broadest possible range of renewable alternatives. Ruling out food crops as a potential energy source won’t help.
When Mr. West converts fruit into ethanol he is turning food into fuel. I believe this is ethically distinct from turning 25% of America’s corn into fuel because:
- The world does not depend on Mr. West’s fruit.
- Fruit prices are usually high enough to keep Mr. West selling his best products as food. Only the culls go to fuel.
- Mr. West is closing resource loops by using the fuel he makes to run his own farm machinery. He is promoting agricultural diversity by making fuel from a wide range of perennial species. I tend to believe in the principals of closing resource loops and promoting biodiversity.
- Mr. West’s facility is not propped up by government subsidies or ethanol mandates. He operates at a small enough scale to have flexibility in the face of changing circumstances.
I suspect it will always take more energy to get sugar from cellulose for fermentation than to get it from high-carbohydrate plants, which tend to be food crops.
A good argument for switchgrass as a feedstock is that it is a native perennial that grows well in mixtures and does not demand a lot of water or fertilizer (Yes, I’m back to biodiversity and resource cycling). But the same could be said of native fruit crops like pawpaw. We might be able to extract more sugar per acre from the cellulose in switchgrass than from pawpaw, but extracting sugar from pawpaw would likely require less energy. In other words, switchgrass could be more land-use efficient, while pawpaw could be more energy efficient. Which crop we use would depend on which resource is most limiting.
America's farms produce roughly 15 pounds of food and animal feed per person per day. About 3 pounds are exported, mostly as grain, and 2.5 pounds are eaten by Americans. Everything else is 'lost' between the farm and the fork. Roughly half is burnt up by the metabolism of our farm animals, which convert it into carbon dioxide and manure.
The people at my lunch table were eating fried chicken as they decried those who would turn food crops into fuel. Although some of the corn that fed those chickens eventually made it through to the meat they were eating, the vast majority was lost to support the animals' metabolism. To me, the decision to dedicate most of the nation's grain to animal production is no more ethical than the decision to dedicate some of it to fuel. There are certainly more sustainable biofuel feedstock crops than corn, but they may well be food crops, like sweet sorghum, sweet potato, or pawpaw.
In the long term we need to move beyond dependence on internal combustion engines that require liquid fuels. In the near term we can begin to wean some of these engines from fossil fuels using biofuels. Food crops likely represent the most sustainable way of producing the raw materials, since humanity has already invested millennia in developing these crops for oil and carbohydrate production. The ethical approach to addressing competition between food and fuel uses is to work toward a world where people can afford the food they need before waste and excess is dedicated to fuel. In economic terms, that means higher farm gate prices for food than for biofuel feedstock, and lower retail prices for food than fuel. This can only happen if the cost of processing crops into fuel is higher than the cost of getting them to the dinner plate, which would tend to be the case if biofuel processing were not subsidized by governments.
If fuel is given a higher priority than food we're in trouble. Our stomachs can be filled, but a century of cheap fuel has shown that our appetite for fuel is virtually limitless.
Hand-cranked corn thresher
Submitted by mkbomford on Thu, 2008-10-23 14:12.An old hand-cranked corn threshing machine made quick work of our field corn.
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Biofuel sustainability standards
Submitted by mkbomford on Thu, 2008-09-25 11:11.Yesterday I had a look at the emerging standards for sustainable biofuel production. I was pulling together information for eXtension.org, an interesting attempt to create a credentialed wiki that draws on the knowledge of land grant university extension personnel. Biofuel sustainability standards are evolving so quickly that the material I contributed to eXtension.org yesterday will likely be long out of date by the time it is published. I thought that readers of this blog might be interested to know a little about ongoing efforts to create national and international standards to certify biofuels as "sustainable." It's an ambitious undertaking.
International Standards
The Roundtable on Sustainable Biofuels, based in Switzerland, has released a draft set of principles and criteria for sustainable biofuels production, as a first step in developing an international standard to be administered by the International Social and Environmental Accreditation and Labeling Alliance (ISEAL). The roundtable is the first large-scale effort to create a global standard for biofuels, although similar efforts for specific fuel feedstocks - including palm oil, soybeans, and sugar cane - are under way.
| Principal | Practice |
|---|---|
| Legality | Follow all applicable laws of the country and international treaties |
| Consultation | Design and operate projects under appropriate, comprehensive, transparent, consultative, and participatory processes that involve all relevant stakeholders |
| Greenhouse Gas Reduction | Mitigate climate change by significantly reducing GHG emissions as compared to fossil fuels |
| Human Rights | Do not violate human rights or labor rights, and ensure decent work and the well-being of workers |
| Development | Contribute to the social and economic development of local, rural and indigenous peoples and communities |
| Food Security | Do not impair food security |
| Ecosystem Conservation | Avoid negative impacts on biodiversity, ecosystems, and areas of High Conservation Value |
| Soil Conservation | Improve soil health and minimize degradation |
| Water Conservation | Optimize surface and groundwater resource use, including minimizing contamination or depletion of these resources, and respecting existing formal and customary water rights |
| Air Conservation | Minimize pollution from production and processing throughout the supply chain |
| Efficiency | Use cost-effective production technology and improve efficiency and social and environmental performance through the use of emerging technology |
| Land Rights | Do not violate land rights |
Teams from Brazil and Germany developing biofuel quality standards for the International Standards Organization (ISO) expanded their mandate to include sustainability criteria in July 2008.
National Standards
The Leonardo Academy released a Draft American National Standard for Trial Use for Sustainable Agriculture in April 2007. The standard includes a section that specifically addresses biofuel sustainability, and would require biofuel processors to calculate the net fossil fuel gain of their products. The standard is modeled on the USDA's National Organic Program standard, and would require third-party certification to sell biofuels labeled 'Certified Sustainably Grown.' The standard is currently going through the American National Standards Institute (ANSI) process, under which it has been contested by the USDA, and defended by the Leonardo Academy.
| Key Element | Practice |
|---|---|
| Sustainable Crop Production | Build and maintain a healthy agroecosystem, based on healthy soil structure and functioning; preferentially employ biological, mechanical, and cultural methods to control pest and disease vectors; minimize agrochemical inputs, favoring the use of reduced risk or US National Organic Program (NOP) permitted agrochemical options; and phase-out those agrochemical inputs that pose significant acute and chronic risks to human health or ecotoxic risks to the environment. |
| Ecosystem Management and Protection | Protect the surrounding ecology including but not limited to waterways, riparian and wetlands habitats, high ecological value habitats and species, and other biologically and culturally significant areas. |
| Resource Conservation and Energy Efficiency | Increase water efficiency, energy efficiency and resource efficiency in all stages of growing, packaging, transporting and handling of crops. Account for greenhouse gas emissions throughout the product life cycle (from seed to store) from all direct and indirect sources, and establish specific greenhouse gas reduction goals. |
| Integrated Waste Management | Compost, recycle, and dispose of agricultural, non-agricultural, and hazardous wastes properly. |
| Fair Labor Practices | Ensure a safe and equitable workplace for agricultural workers, addressing such issues as equitable hiring and employment practices, safe workplace conditions, workers' right to organize, worker housing, child labor, access to health, education, and transportation services. |
| Community Benefits | Support local communities through preferential purchasing, hiring, and improvements or development, as well as addressing impacts caused by agricultural operations. |
| Product Quality | Ensure product quality throughout the chain-of-custody and establish quality assurance and traceability requirements designed to ensure that sustainably grown products are properly handled and can be traced back to their source. |
| Product Safety and Purity | Conform to minimum acceptable food safety practices and food purity requirements for edible crops. |
Michael Bomford provides research and extension services related to organic agriculture and small-scale renewable energy production through Kentucky State University's Land Grant Program.
High winds and high tunnels
Submitted by mkbomford on Mon, 2008-09-22 09:24.
The remnants of Hurricane Ike lashed through our farm last weekend and tore the plastic off our high tunnel (right). I was surprised by the ferocity of the wind, given that the center of the storm didn't even hit Kentucky. Much of our region was without power for most of the week, and many schools are just re-opening today, eight days after the storm.
The high winds didn't do much damage to our Energy Farm study plots. The field corn and soybeans have been drying in the field (letting the sun do the work saves a lot of the energy that would be used by drying bins). The plants stayed standing, but the beans lost their leaves, which will actually make our harvest easier. The sweet sorghum stood up to the wind too. Sweet potatoes, with their soil-hugging vines and most of their biomass below ground, are pretty much wind-proof.
In 2006 I had sweet sorghum growing right next to the high tunnel when heavy winds came through at about the same time of year. The high tunnel survived but the sorghum came down (left). What was the difference? I can only speculate:
In 2006 the winds came with rain, which softened the soil and left the tall plants more vulnerable to lodging. This year the winds came after a month of drought, and didn't bring a drop of rain. The soil is hard, and the plants stood firm. Another possible difference is that the tunnel was protected by the sorghum in 2006; the crops growing next to the tunnel this year were much shorter. Finally, the tunnel walls were rolled down when the winds hit in 2006, but were rolled up for ventilation when the winds hit last week. That allowed the wind to get under the tunnel and start to work away at the sides.
The use of high tunnels has important energy implications. Using only passive solar heat, a high tunnel uses much less energy than a heated greenhouse (My figure below, with more here... Thanks to Dr. Yoshihiko Wada for his data on greenhouse energy consumption).
Both high tunnels and heated greenhouses can allow year-round vegetable production in many regions, which reduces the need for winter trucking of produce. The difference is that only cool-season crops (e.g. lettuce, carrots, beets) will grow in the high tunnel through the depth of a Kentucky winter, but a heated greenhouse can keep warm season crops (e.g. tomatoes, cucumbers, peppers) going all year long. Although it's nice to have locally-grown tomatoes in February, it would actually take far less energy to grow field tomatoes in Mexico and truck them to Kentucky than to heat the Kentucky greenhouse that would allow winter production of warm season crops. The high tunnel can give us fresh kale and carrots in February, and tomatoes as early as May. Outside the tunnel the kale dies in December and tomatoes don't bear fruit until the beginning of July.
We use two layers of plastic on our high tunnel. Between them is an insulating air pocket, maintained by a 60 W blower fan that runs continuously. As the figure above shows, the blower fan adds a lot to the energy needed to maintain the high tunnel. Many others use a single layer of plastic, which doesn't retain heat as well, but eliminates the need for a blower fan.
Like high tunnels, greenhouses are vulnerable to wind. When I worked in large glass greenhouses in British Columbia managers would keep a nervous eye on the data coming continuously from wind speed sensors (anemometers) on the roof. They knew they had to get their workers out in a hurry during heavy winds because the glass panes would start to shatter, with potentially fatal results.
I can't imagine that heated greenhouses will have much place in an energy constrained future. Those who promote vertical farming in urban areas apparantly disagree. That could be fodder for another blog post.
Michael Bomford provides research and extension services related to organic agriculture and small-scale renewable energy production through Kentucky State University's Land Grant Program. He thanks Tony Silvernail, Brian Geier and John Rodgers for their help with maintaining the organic land at the KSU Research Farm.
Preliminary Data: KSU Energy Farm in August
Submitted by mkbomford on Fri, 2008-08-29 14:39.
Our harvest has begun. This week we collected 1,259 lbs (571 kg) of edamame soybean plants, weighed down with 655 lbs (297 kg) of beans. Soybeans are usually allowed to mature and dry on the plant, then harvested as the dry bean used to make tofu, soy sauce, waxes, artificial plastics, soyfoods, animal feed, and biodiesel. Edamame soybeans are harvested green, like green beans, to be eaten as vegetables.
We harvested our biointensive and market garden plots by hand, and cut the small farm plots with a sickle-bar mower attached to a walk-behind tractor. The picture below shows Tony Silvernail cutting beans in a small farm plot. Sweet potatoes are in the foreground, with corn and sorghum in the background.
We separated the beans from the plants using a simple slotted board design from the Asian Vegetable Research and Development Center. It sped the bean picking process considerably.
We recently had to irrigate for the first time, because we've gone about three weeks without rain, but maintaining the study has taken less time and energy in August than in previous months. Here are the updated charts, showing labor in minutes per square meter and energy in megajoules per square meter since May:
Now that we have collected our first yield data, it is possible to calculate the land, labor, and energy use efficiency for edamame soybeans grown at each of our farm scales. Yields are usually presented as the amount harvested per unit area (e.g. tons/acre, kg/ha). The blue bars on the chart below show the weight of edamame soybeans harvested from each square meter of land, giving a measure of land use efficiency at each of the three farm scales. The maroon bars show yield per megajoule of energy invested, and the yellow bars show yield per minute of labor invested. These measures of energy and labor use efficiency are less typical ways of measuring yield.
The edamame soybean yield suggests that each of the farm scales has a different strength: The biointensive scale was the most energy efficient; the market garden scale made the most efficient us of land; and the small farm scale made the most efficient use of labor.
Michael Bomford provides research and extension services related to organic agriculture and small-scale renewable energy production through Kentucky State University's Land Grant Program. He thanks Tony Silvernail, Brian Geier and John Rodgers for their help with maintaining the organic land at the KSU Research Farm.
Fox News: Louisville's Progressive Media Outlet
Submitted by mkbomford on Fri, 2008-08-01 12:24.I don't usually choose to watch Fox News. I frequently cringe when it is inflicted upon me in airports or doctors' waiting rooms. So when a Fox reporter called to say she wanted to interview me about organic agriculture I was a little nervous. Was I being set up for public ridicule of hippie food, yuppy food, or worse?
To my surprise and relief, it turned out to be a straight-up, feel-good piece about the benefits of organic agriculture.
OK, so they included a lot of supermarket shots of industrial organic produce, trucked from afar, which probably isn't the most sustainable. And the closing comments (the way to tell it's really organic is by the number on the bar code) would probably leave the likes of Eliot Coleman or Joel Salatin doubled over in pain or mirth.
There's some learning left to do, but they were taking this stuff seriously. This week they also ran segments on growing your own food, shopping at farmers markets, and getting energy from wind, hydro, and used vegetable oil. They suggested their viewers stop mowing their lawns, and touted the benefits of green building and straw bale construction. They pushed reducing, reusing and recycling. Remember, this isn't Mother Earth News, it's Fox.
Isn't it amazing what $4 gas will do?
