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  • From: "Douglas Willhite" <drwillhite@earthlink.net>
  • To: <livingontheland@lists.ibiblio.org>
  • Subject: [Livingontheland] Food & agriculture news - May 7
  • Date: Tue, 8 May 2007 08:20:11 -0700

Food & agriculture news - May 7

Articles included below:

1. Questioning the compost supply chain
by Deborah K. Rich, SF Chronicle

2. 100-Mile Diet

by J.B. MacKinnon and Alisa Smith, The Tyee

3. As the climate warms, gentler plants move in
by Michael Milstein, Portland Oregonian

4. No More Scrod
by Sharon Astyk, Casaubon's Book

5. Could the Mysterious Agricultural Techniques of an Ancient Amazonian Civilization Make New Zealand Farming More Competitive?

by David Haywood, Public Address


Questioning the compost supply chain

Deborah K. Rich, SF Chronicle
As politicians increasingly use composting to solve municipal waste and recycling issues, what happens to the pesticides, herbicides and pharmaceuticals that may have gone into the mix along with the lettuce leaves.
----
If soil, which breaks down fallen plant and animal materials, can be likened to the Earth's liver, then composting is becoming the liver of modern society -- tasked with processing and reducing lawn clippings, food scraps, manure and sewage. Given the chemicals we spray on our lawns, feed our livestock and swallow to keep us happy and functioning, are we asking too much of our collective microbial liver? Can composting detoxify chemicals, or are we spreading heavy metals, pesticides and drug residues in our gardens?

The answers to these questions are uncertain.

Composting is the mixing and management of organic waste (plant and animal materials and byproducts) to achieve ratios of carbon to nitrogen that accelerate and maximize microbial degradation of organic matter. By harnessing the power of microbes, municipalities can reduce and recycle plant and animal waste even where land and time are too scarce to accommodate the soil's comparatively slow rate of decomposition. "By composting, you are duplicating what nature would do given the chance," says Dale Arnold, director of quality control and research at Kellogg Garden Products. Kellogg sells compost and other soil amendments to 3,500 independent retail nurseries, as well as Home Depot and Lowe's. "Nature takes a long, long time to make compost. All we're doing is speeding up that natural cycle."

Yard trimmings, wood waste from construction, animal manure, agricultural byproducts and biosolids from sewage treatment plants are the primary feedstock for the roughly 170 composters and waste processors that operate in California.

...Often these feedstock materials enter the composting process still laden with chemicals. Yet standards for finished compost, which vary from state to state, generally require regular testing only for heavy metals and pathogen indicators. Seldom do states ask that producers test their compost for residual pesticide or pharmaceutical compounds.

Unlike farmers composting manure and plant residues for their own use, gardeners purchasing compost at a nursery seldom know what went into the compost, where the feedstock came from or what chemicals were on them.

"Compost," says William Brinton, founder and president of Woods End Laboratories in Maine and a pioneer of modern compost production and testing systems in the United States, "has become anonymous and untraceable; a single compost product can now contain a mixture of unknown ingredients from all over a county or a state."

The compost supply chain is poised to become even more difficult to trace as city and state politicians turn to composting as a means to meet their solid-waste reduction goals. "Composting now is being driven by recycling mandates set by politicians," Brinton says. "When I got my start in the composting world in the '70s, our motivation was to create products that nourished the soil. That was the goal, and then we worked backwards and asked how do we take ingredients like manure and crop residues and make wonderful compost for the soil?

"Now it's the cart pulling the horse: The recycling cart is pulling the compost horse. I'm not saying the goals of making good soil amendments and recycling are incompatible. I'm saying that this sets up the challenge to maintain the integrity of compost, a challenge that will become more intense as the industry grows even larger."

...As our dependence on compost to both reduce our organic wastes as well as to maintain the health of our soils grows, composting without a more complete understanding of the fate of chemicals in compost becomes increasingly risky.

"I believe that composting is the best tool that we have for handling many of the different types of organic materials that we use," says Richard of Pennsylvania State University. "It can reduce their impact significantly and at lower cost than other options that we have, and we really do need to have a society that does a better job of recycling its organic matter.

"But we need to look pretty hard at a lot of these different compounds. We are depending on composting to handle increasing amounts of the 50 percent-plus of our waste stream that is organic. To not be studying these emerging questions seems to be pretty naive."
(7 May 2007)



100-Mile Diet: Hand Picked from the Blog
J.B. MacKinnon and Alisa Smith, The Tyee
The idea of "food miles" continues to be a great wake-up call to get people thinking about long-distance food -- it was a big part of what inspired Alisa and me to try a 100-mile diet. But it's important that food miles do not become the start and end of the argument. A lot of powerful interests are deeply invested in the current food system and highly resistant to change, and these automatic critics are looking at food miles as local eating's Achilles heel.

The fact is that even when it comes to energy use and fossil fuel consumption, food miles aren't much of a measure. A better bet is what's called a "life cycle assessment," which attempts to measure the impacts of food production from "cradle to grave." Unfortunately, life cycle assessments are complex, highly specific, and have been performed for only a small number of foods.

What a life cycle assessment may show can be surprising. For example, the emerging critics of local eating -- yes, there are people who have a problem with you and I choosing to buy our food from people in our own communities -- often point to the "tomato study." Research for the Department for Environment, Food and Rural Affairs in the U.K. found that it can be more energy efficient to ship in field tomatoes from Spain than to grow tomatoes in the U.K.

...Well, not so fast.

"The problem with life-cycle assessments," said my friend and systems analyst Ruben Anderson, who has grown a bit of a beard and now looks even wiser, "is that they can only compare systems within the current paradigm."

You see what he means if you give more than a glance at the tomato study. The fine print is this: it compares Spanish tomatoes that travel thousands of miles to U.K. tomatoes that are grown in gas-fired greenhouses from February to November, far beyond the natural tomato growing season.

Each of the more controversial life-cycle studies makes these kinds of comparisons, pitting unsustainable systems against unsustainable systems. To examine the New Zealand study and conclude that the best way forward is to continue shipping 11,000-mile apples is particularly ludicrous. A more rational message is clear: Britain needs to shift toward less energy-intensive forms of agriculture, such as organics.
(7 May 2007)




As the climate warms, gentler plants move in

Michael Milstein, Portland Oregonian
Backyard - A debate rages, however, over how much to alter the gardener's venerable guide: the rainbow-like hardiness map
----
New Zealand flax, a decorative plant with sword like leaves, used to have a hard time surviving Oregon's winters. But the past dozen years have been so mild, the plants now flourish, lending an exotic touch to more and more Oregon backyards.

"Plants in the past that have not survived more than a year or two are now surviving six or seven," said Paul Bonine, co-owner of Xera Plants, a wholesale nursery in Sherwood.

It appears increasingly that global warming, nudging temperatures up and easing winters, helps gardeners grow plants once frozen out. The trend is altering the rainbow-colored plant hardiness map that splits the nation into zones based on how cold they get.
(6 May 2007)


No More Scrod
Sharon Astyk, Casaubon's Book
...By now most of you may have read the study that says that the oceans will be entirely depleted of edible fish by 2048 at present rates of consumption. Now speaking as a girl from the Massachusetts coast, the granddaughter and step-sister of fishermen, and someone who thinks that there really is no such thing as too much sushi, fish is practically an article of faith. And within my lifetime, it may all be gone. I've cut way back on fish over the last few years, because mercury and PCB contamination are bad news for pregnant women and nursing mothers, but I do miss it.

Now this is terrifically sad for me, of course - my culture too is tied up in its food - but it is really terrifying for people whose indigenous diets revolve around fish. Most Island and Arctic peoples rely on fish for a large percentage of their diet. They're already struggling with rising seas, melting ice and mercury and PCB contamination of their staple food - and now they stand to lose fish altogether.

There are 1 billion people who rely on fish or fish predators as their primary source of animal protein, and another 3 billion people who eat it regularly. But the big problems come from industrialized nations - the US, Japan, Britain, where we increasingly want to eat a lot of fish and seafood imported from far away. Our own waters are depleted, so we go off to the waters of other people, and take their fish. And the oceans cannot endure it.

This is an even bigger problem because we are entering a period in which food supplies themselves are destabilizing.
(6 May 2007)



Could the Mysterious Agricultural Techniques of an Ancient Amazonian Civilization Make New Zealand Farming More Competitive?

David Haywood, Public Address
A month or so ago, I wrote an article on Public Address in which I implied that it would be very difficult to reduce greenhouse gas emissions from New Zealand agriculture. Well, it turns out that perhaps I was being unduly pessimistic -- as structural biologist Alfred Harris has subsequently explained to me.

Alfred's good-news story begins -- like all the best stories -- with a mysterious substance hidden deep in the Amazon region of South America. Terra Preta de Indio or 'Amazonian Dark Earths' are areas which contain soil of exceptionally high fertility.

Naturally enough, scientists were very keen to find out what made these soils so special -- but no-one expected the answer that they got. It turns out that these soils were actually man-made.

Pre-European Amazonians had manufactured these soils by working charcoal and manure into ordinary low-fertility earth. Of course, the fertilizing properties of manure are well-known, but it was the addition of charcoal which dramatically improved soil fertility. So much so, in fact, that the soil was still extremely fertile hundreds of years after the collapse of the civilization that produced it.

And here's an interesting co-incidence -- go a third of the way around the world to New Zealand, and archaeologists discover that pre-European Maori also worked charcoal into the soil to improve fertility.

It seems like an extraordinary co-incidence. Structural biologist Alfred Harris takes up the story...

Alfred Harris: In Waimea, for example -- where there's hundreds of acres of what they call 'Maori soils' -- the experimental work was done on that site, and it was very clear that charcoal was mixed far further into the soil than would be expected simply from just the burning of the site.

Interviewer: It's fascinating that two cultures so far apart should both discover the effects of charcoal in terms of agriculture. At a scientific level, how the does charcoal actually improve soil fertility?

...Voiceover: So it's possible that the use of charcoal in New Zealand agriculture could reduce fertilizer use, save energy, and sequester carbon all at the same time. With rising petroleum costs it seems like maybe the time has come to re-learn a few lessons about charcoal from the ancient Amazonians [and pre-European Maori].
(5 May 2007)



  • [Livingontheland] Food & agriculture news - May 7, Douglas Willhite, 05/08/2007

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