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Where the Rubber Meets the Road: Ecological Economics and Intensive Vegetable Cultivation

Submitted by jcbradford on Mon, 2008-02-11 17:08.

 

"Can
we rely on it that a ‘turning around' will be accomplished by enough people
quickly enough to save the modern world? This question is often asked, but
whatever answer is given to it will mislead. The answer "yes" would lead to
complacency; the answer "no" to despair. It is desirable to leave these
perplexities behind us and get down to work."
E.F. Schumacher, Small is
Beautiful

I would rather have titled this essay "Where the Hoe Meets
the Soil" but that phrase is not part of our cultural lexicon, which is itself
a symptom of the problem I am working to address. Setting aside any prolonged discussion of
whether or what about the modern world should be saved, this essay is primarily
about what it means to "get down to work" as Schumacher puts it. But very quickly, to me saving the modern
world means setting a goal for the human economy to be properly scaled relative
to the global ecology, and maintaining a sufficiency of social stability
necessary to manage a transition.

 

Before getting to work, I want to make sure the work I do is
useful. This is where a clear
understanding of the big picture helps.

 

Ecological Economics

The question of proper economic scale is examined by the field of ecological
economics. In the ecological economics
model, the human economy is a subset of the Earth system, and therefore the scale
of the human economy is ultimately limited.
The human economy depends upon the throughput or flow of materials
from and back into the Earth system.
Limits to the size of the human economy are imposed by the interactions
among three related natural processes:

(1) The capacity of the Earth system to supply inputs to the human economy
(Sources),

(2) The capacity of the Earth system to tolerate and process wastes from the
human economy (Sinks), and

(3) The negative impacts on the human economy and the resources it relies on
from various feedbacks caused by too much pollution.

 

 

Fig. 1. The ecological economics model
of the relationship between the human economy and the Earth system highlighting
the importance of sources, sinks, feedbacks and scale.[i]

For an expanded look at the relationship between our economy and the planet
see the engaging on-line film "The Story of Stuff."[ii]

One measure of whether the human economy is too large is the
ecological footprint (EF), which calculates on a nation-by-nation basis the
consumption of resources and the build-up of wastes relative to resource regeneration
rates and the waste-absorbing capacity of the environment. According to two independent EF analyses (which
I will call EF 1 and EF 2) the human economy (population plus consumption and
waste generation) is in a state of overshoot, meaning it is too large relative
to the long-term capacity of the planet to cope.[iii] The Earth can provide for us beyond its means
for a long time before the consequences become severe, just like a millionaire
can, for a time, live high on the principal in a savings account instead of the
interest. The degree to which we are
drawing down principal as opposed to living on interest is called our
"ecological debt."

 

 

Figure 2. Change in
ecological footprint over time according to EF 1 with our cumulative ecological
debt in blue.[iv]

 

Getting More Specific:
Fossil-fuel Depletion and Climate Change

 

Indicators like the ecological footprint are important for
understanding we have a problem and giving us a sense of the scale, but they
aren't very specific. In order to do
something about reducing our footprint, it would help to know what is causing
the ecological footprint to be so large.
A significant portion of the ecological footprint represents consumption
of fossil fuels and the resulting waste, mainly greenhouse gases. The "carbon" footprint component is about 52%
for EF 1 and the similar "energy land" is 88% for EF 2.[v] According to EF 2, "energy land" is 93% of
the North American footprint. A priority
on reducing fossil fuel consumption appears justified. The human ecological footprint can be lowered
below "1 Earth" only by eliminating the pollution from fossil fuel
combustion.

 

EF analysis uses the capacity of the environment to absorb
greenhouse gas emissions, which, as seen in the model shown in Fig. 1, means EF
measures "sink" capacity. The real
picture is more complex and more disturbing for a couple of reasons. Firstly, fossil fuel extraction is reaching
limits sooner than expected. Since we
have not been weaning our economy off fossil fuels steadily for the past few
decades, rapid energy price inflation will likely make it difficult to maintain
the kind of economic vitality and stability needed for a smooth transition to
renewable energy alternatives. Secondly,
recent evidence suggests that climate change is happening faster than
expected. Ice sheet destabilization is
one major indicator that the Earth system is more sensitive to greenhouse
emissions than most scientists and policy-makers have presumed. Recent articles by Kurt Cobb[vi]
and Richard Heinberg[vii]
review all these points, and the "Climate Code Red" report[viii]
goes into truly excruciating detail so I won't elaborate further here.

 

The bottom line is that every measure must be taken to
rapidly eliminate fossil fuel consumption and dependency in every component of
our lives. The key word is
"rapidly." Don't passively assume
inexpensive alternative energy substitutes will arrive to replace fossil fuels-we
may have waited too long to respond to have a smooth transition. Therefore, focus most attention on reducing
energy demand rather than substituting a new energy supply. And finally, in the context of ecological
economics, fossil fuel depletion and climate change, ask whether what you do in
your life, vocation, hobbies, and habits, contributes to the long-term function
(or dysfunction) of society.

 

The U.S.
Food System and Fossil Fuels

It would be hard to argue against a claim that a secure and
healthy food supply is indispensable to society. A widely known and troubling fact is that the
current food system in the U.S.
(and most highly industrialized nations) is very dependent upon fossil
fuels.

 

As far as I am aware, the most comprehensive study on the
topic of energy use in the U.S.
food system is by Heller and Keoleian of the University of Michigan's
Center for Sustainable Systems.[ix] The report is from 2000 and makes use of data
from the mid-1990s. Although the data
are about 10 years old, I don't believe the basic structure and function of the
U.S.
food system has changed dramatically over the past 10 years. In fact, current trends of increased
industrial meat consumption[x]
and biofuels[xi], which
both rely on grains, make the following case even stronger.

 

We learn from the study that over 10% of the energy
consumption in the U.S.
can be attributed to the food system, and that about 20% of this occurs in the
agricultural production sector. Home
energy consumption (e.g., refrigeration and cooking) consume the largest share
at about 30%. Between the farm and the
home are everything else (transportation, processing, packaging and
retail). Much of this middle portion is
a function of the geographic disconnection between production and
consumption. Eating food out of season
either requires long-distance transportation or energy demanding
processing. Both transportation and
processing require investments in storage.

 

Sorting out the proper scale of operations for farms,
processing and transportation systems is very difficult, however, because optimization
for one factor (e.g., transportation), may be sub-optimal for another (e.g.,
heat intensive food processing). Within
a category, such as transportation, the technologies analyzed may be limited
too. A study comparing rail cars, large
semi-trucks and small produce trucks may conclude that bigger is better, but
what about hyper-local transportation systems using bikes, small electric
vehicles and bipedal locomotion? Another
complicating issue is that studies may assume the U.S. food system should be more or
less similar in its mix of products while lowering energy consumption. For example, tomatoes can be processed using
canning or drying. Canning lends itself
to centralized operations and so does drying if fossil fuels are used as heat
sources. But a naturally decentralized
and fossil-fuel free technique such as passive solar dehydration may not even
be considered. Large energy savings can
be found everywhere in the food system, but especially so if assumptions about scale
and consumer-level demand are allowed to change.

 

Fig. 3. The energy
inputs to the U.S.
food system are several times larger than the energy content of the food. A life-cycle analysis identifies how energy
consumption is partitioned among economic sectors.[xii]

 

Another graphic from the Heller and Keoleian report clearly
identifies a huge savings potential.
Over 50% of U.S.
grains are fed to domestic animals, and most export grains go to animal feed as
well. Overall, only 26% of U.S. grain
production in 1995 went to domestic human consumption.

 

Although poultry need grains, red meat and milk products
dominate the feed market and grains are not a natural part of their diets. If red meat and dairy production were reduced
to only what harvested hay and pasture could provide, perhaps half of annual U.S. grain
production could be eliminated. The
acreage out of food production could be used for green manure crops to build
soil and fix nitrogen. A 2004
Congressional Research Service report showed that fertilizers are the largest
part of farm energy use, and that natural gas to produce nitrogen comprised
75-90% of the fertilizer input (Fig. 5).[xiii] Fixing nitrogen naturally, therefore, saves
significant energy. Some of the vast
cropland area no longer producing grains could then be used for appropriately
scaled biofuels to power farm equipment instead of fossil fuels.

 

 

Fig.
4. A reprint of Fig. 3 from the Heller
and Keoleian report. See graph label
above.

 

Fig.
5. A reprint of Fig. 2 from a 2004
Congressional Research Service report.
See graph label above.

 

An older and less comprehensive on-line
review paper[xiv] titled "Energy Use in the U.S. Food System: a summary of existing research and
analysis" by John Hendrickson of the Center for
Integrated Agricultural Systems, UW-Madison concluded that:

 

"It appears that some of the greatest
saving can be realized by:

 

  • reduced use of petroleum-based fertilizers and
    fuel on farms,
  • a decline in the consumption of highly processed
    foods, meat, and sugar,
  • a reduction in excessive and energy intensive
    packaging,
  • more efficient practices by consumers in shopping
    and cooking at home,
  • and a shift toward the production of some foods
    (such as fruits and vegetables) closer to their point of consumption."

 

Hendrickson's paper is helpful in republishing and comparing
tables from many previous studies, including "Table 5" reprinted here on the
energy consumption of home grown versus market-purchased fruit and
vegetables.

 

Taking Responsibility: Brookside Farm Examples

 

With this extensive background I introduce the project I
have been working on for about two years now, Brookside Farm. This is a 1-acre mini-farm in Willits, CA. It operates as a program of the non-profit
corporation North Coast Opportunities, functions as a working farm with a
community supported agricultural program serving 15 "shares" per year, exists
at an elementary school and is therefore open to classes and tours, and
conducts research and demonstrates aspects of a local food system with the collaboration
and support of Post Carbon Institute.[xv]

 

Brookside Farm thinks about food from a "farm to fork" and
back again perspective. Farmers create
artificial ecosystems, and we therefore look to ecology to guide our
practices. Highly productive and stable
ecological systems are noted for a diversity of species both in kinds and
functional forms. When these diverse
species interact effectively, they maximize the rates of productivity and
nutrient retention in the system using ambient energy sources. We view ourselves as human members of the farm
ecosystem with our labor and wastes as parts of the whole.

 

To get by on ambient energy as much as possible, we have
sought alternatives to fossil fuels in every aspect of the food system we
participate in. Table 1 considers each
type of work done on the farm, to the fork, and back again and contrasts how
fossil fuels are commonly used with the technologies we have applied.

Type of Work

Common Fossil-Fuel
Inputs

Alternatives
Implemented

Soil cultivation

Gasoline or diesel powered rototiller or small tractor

Glazer hoe, broadfork, adze, rake and human labor

Soil fertility

In-organic or imported organic fertilizer

Growing of highly productive, nitrogen and biomass crop
(banner fava beans), making aerobic compost piles sufficient to build soil
carbon and nitrogen fertility, re-introducing micro-nutrients by importing
locally generated food waste and processing in a worm bin, and application of
compost teas for microbiology enhancement.

Pest and weed management

Herbicide and pesticide applications, flame weeder,
tractor cultivation

Companion planting, crop rotation, crop diversity and
spatial heterogeneity, beneficial predator attraction through landscape
plantings, emphasis on soil and plant health, and manual removal with
efficient human-scaled tools

Seed sourcing

Bulk ordering of a few varieties through centralized seed
development and distribution outlets

Sourcing seeds from local supplier, developing a seed
saving and local production and distribution plan using open pollinated
varieties

Food distribution

Produce trucks, refrigeration, long-distance transport,
eating out of season

Produce only sold locally, direct from farm or hauled to
local restaurants or grocers using bicycles or electric vehicles, produce
grown with year-round consumption in mind with farm delivering large
quantities of food in winter months

Storage and processing at production end

Preparation of food for long distance transport, storage
and retailing requiring energy intensive cooling, drying, food grade wax and
packaging

Passive evaporative cooling, solar dehydrating, root
cellaring and re-usable storage baskets and bags

Home and institutional storage and cooking

Natural gas, propane or electric fired stoves and ovens,
electric freezers and refrigerators

Solar ovens, promotion of eating fresh and seasonal foods,
home-scale evaporative cooling for summer preservation and "root cellaring"
techniques for winter storage

 

Table 1. Feeding
people requires many kinds of work and all work entails energy. In most farm operations the main energy
sources are fossil fuels. By contrast,
Brookside Farm uses and develops renewable energy based alternatives.

 

Our use of food scraps to replace exported fertility also
reduces energy by diverting mass from the municipal waste stream. Solid Waste of Willits has a transfer station
in town but no local disposal site. Our
garbage is trucked to Sonoma
County about 100 miles to the south.
From there it may be sent to a rail yard and taken several hundred miles
away to an out of state land fill.

 

We are also planning to irrigate using an on-site well and a
photovoltaic system instead of treated municipal water or diesel-driven
pumps.

 

How much energy does Brookside Farm
save?

The complexity of the food system makes it difficult to
calculate how much energy Brookside Farm is saving. A research program at UC Davis now devoted to
just this sort of question is recently underway, but with few results to share
thus far.[xvi]

 

From previous studies we can find clues about the high
energy inputs to fruit and vegetable cultivation. From Fig. 4. above, we can see that fruits
and vegetables account for (102,370/921,590) 11% of crop production by weight. Table 3 (given below) of the Congressional
Research Service report shows that energy invested in fruit and vegetable
production is proportionally higher, accounting for (3759/18364) 20% of the
energy for crops at the farm level.

 

 

Much of the savings at Brookside Farm occurs off the farm by
replacing what would normally be imported, through passive solar preservation
and storage techniques, and by shifting consumer habits towards seasonally
fresh cuisine proportionally high in vegetables.

 

Does Brookside Farm Scale? Lawns to Food

Before it was Brookside Farm, it was a field of mostly grass
at an elementary school. The school
district watered and mowed it (Fig. 6).

 

Fig. 6. Brookside
Farm in early spring, 2007. The image
shows the farm site adjacent to the forest and bordered by grassy fields,
school buildings and a residential neighborhood. Arrows from a home contrast distance and
direction of food coming from the local Safeway supermarket and Brookside
Farm. The 1 acre Brookside Farm occupies
about a quarter of the available play field at Brookside Elementary School.

 

Using satellite imagery, the area of lawn in the United States
has recently been estimated:

"Even conservatively," Milesi says,
"I estimate there are three times more acres of lawns in the U.S. than irrigated corn." This means
lawns-including residential and commercial lawns, golf courses, etc-could be
considered the single largest irrigated crop in America in terms of surface area,
covering about 128,000 square kilometers in all.[xvii]

 

 

The same study identifies where and how much water these
lawns require:

That means about 200 gallons of
fresh, usually drinking-quality water per person per day would be required to
keep up our nation's lawn surface area.

 

Let me put the area of lawn from this study into a food
perspective. The 128,000 square
kilometers of lawns is the same as 32 million acres. A generous portion of fruits and vegetables
for a person per year is 700 lbs, or about half the total weight of food
consumed in a year.[xviii] Modest yields in small farms and gardens would
be in the range of about 20,000 lbs per acre.[xix] Even with half the area set aside to grow
compost crops each year, simple math reveals that the entire U.S. population could be fed plenty
of vegetables and fruits using two thirds of the area currently in lawns.

 

Number
of people in U.S.

Pounds
of fruits and vegetables per person per year

Yield
per acre in pounds

People
fed per acre in production

Fraction
of area set aside for compost crops

Compost-adjusted
people fed per acre

Number
of acres to feed population

Acres
in lawn

Percent
of lawn area needed

300,000,000

700

20,000

29

0.5

14

21,000,000

32,000,000

66%

 

Labor Compared to Hours of T.V.

 

For its members Brookside Farm's role is to provide a
substantial proportion of their yearly vegetable and fruit needs. Using our farming techniques, we estimate
that one person working full time could grow enough produce for ten to twenty
people. By contrast, an individual could
grow their personal vegetable and fruit needs on a very part-time basis,
probably half an hour per day, on average, working an area the size of a small home (700 sq ft in veggies and fruits plus 700 sq ft in cover crops).

 

American's complain that they feel cramped for time and
overworked. But is this really true or
just a function of addiction to a fast-paced media culture? According to Nielsen Media Research:[xx]

The total average time a household
watched television during the 2005-2006 television year was 8 hours and 14
minutes per day, a 3-minute increase from the 2004-2005 season and a record
high. The average amount of television watched by an individual viewer
increased 3 minutes per day to 4 hours and 35 minutes, also a record. (See
Table 1.)

 

So if we imagine families having the discipline to cut out a
single sitcom viewing per day, or one baseball or football game per weekend
during the growing season, that would free-up sufficient time to become
self-reliant in fruits and vegetables and likely improve overall health.[xxi]

 

(A note of caution though, an article from The Onion warns
"that viewing fewer than four hours of television a day severely inhibits a
person's ability to ridicule popular culture.")[xxii]

 

Conclusions

 

For those wanting to contribute to a lower-energy food
system, starting with fresh produce makes sense for several reasons:

(1) Significant production is possible in a small area,
often what people already have,

(2) Tools and equipment are simple, inexpensive and readily
available,

(3) Fruits and vegetables are heavy due to high water
content, and therefore energy-intensive to transport and process either by
canning or dehydrating,

(4) Growing vegetables and fruits is generally more energy
intensive than other crops because of high fertilizer and irrigation inputs,

(5) Quality declines rapidly after harvest, so home or
locally available food has higher nutritional value and usually tastes better,

(6) Labor, packaging and storage demands of fruits and
vegetables are high in mechanized production systems, making the investment in
home-grown produce financially competitive, and

(7) Gardening and small-scale fruit and vegetable farming
lend themselves to physical and social activities across generation and income
gaps that improve health and enhance a shared sense of purpose and fun.

 


[i] This
graphic was developed based on the principles discussed in Chapter 2 of Daly
and Farley "Ecological Economics:
Principles and Applications" (2004, Island Press)

[ii] http://www.storyofstuff.com/

[iii] http://www.footprintnetwork.org and
http://www.rprogress.org/ecological_footprint/about_ecological_footprint.htm;
the original ecological footprint analysis (EF1) is at the first reference, and
the second type (EF2) at the second. The
major difference between the two is that the second attempts to incorporate
aquatic systems (e.g., oceans), total terrestrial productivity, and
biodiversity reserves.

[iv] Graphic
from: http://www.footprintstandards.org/

[v] For the
50% figure see: http://www.footprintnetwork.org/gfn_sub.php?content=global_footprint; for the greater than 90% and discussion of
differences between methods see: http://www.rprogress.org/publications/2006/Footprint%20of%20Nations%2020...

[vi] http://scitizen.com/screens/blogPage/viewBlog/sw_viewBlog.php?idTheme=14&idContribution=1397

[vii] http://globalpublicmedia.com/richard_heinbergs_museletter_big_melt_meets_big_empty

[viii] http://www.climatecodered.net/

[ix] http://css.snre.umich.edu/main.php?control=detail_proj&pr_project_id=29

[x] See
especially Table 2. in: http://www.fao.org/docrep/005/AC911E/ac911e05.htm

[xi] http://www.theoildrum.com/node/2431

[xii]
Graphic from: http://css.snre.umich.edu/css_doc/CSS01-06.pdf

[xiii] http://www.ncseonline.org/NLE/CRSreports/04nov/RL32677.pdf

[xiv]
Although no date appears on this paper, it is clearly related to a 1994
conference and workshop: http://www.cias.wisc.edu/pdf/energyuse.pdf;
http://www.cias.wisc.edu/archives/1994/01/01/energy_use_in_the_us_food_system_a_summary_of_existing_research_and_analysis/index.php

[xv] http://www.energyfarms.net/

[xvi] http://asi.ucdavis.edu/conferences/farmtofork/;
http://californiaagriculture.ucop.edu/0704OND/editover.html;
http://asi.ucdavis.edu/Research/ASI_Program_Proposal_Brief_-_Energy_Life_Cycle_Assessment_in_Food_Systems_9-13.pdf

[xvii] http://earthobservatory.nasa.gov/Study/Lawn/

[xviii] http://www.ers.usda.gov/Data/FoodConsumption/FoodGuideIndex.htm

[xix] An
acre is ca. 43,000 sq ft. Our experience
at Brookside Farm suggests about 1 lb of produce per square foot of cultivated
space is to be expected, with infrastructure and paths requiring significant
area. Fruit orchards in Mendocino County yield about 20,000 lbs per
acre: http://www.co.mendocino.ca.us/agriculture/pdf/2006%20Crop%20Report.pdf

[xx]http://www.nielsenmedia.com/nc/portal/site/Public/menuitem.55dc65b4a7d5adff3f65936147a062a0/?vgnextoid=4156527aacccd010VgnVCM100000ac0a260aRCRD

[xxi] http://www.csun.edu/science/health/docs/tv&health.html

[xxii] http://www.theonion.com/content/node/30863



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