Iowa State University Extension Fundamentals of Organic Agriculture - Transition to Organic Partnership Program

Detailed information on organic agriculture including history, legalities and logistics, labeling, marketing, and pest and weed management. Includes two field examples on organic soybean and apple production.
Midwest

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2003

Organic Agriculture
The primary goal

What Is Organic Agriculture?

of organic agriculture
is to optimize
the health

and productivity

of interdependent

According to the National Organic Standards Board (NOSB) of the United States
Department of Agriculture (USDA), organic agriculture is “an ecological production
management system that promotes and enhances biodiversity, biological cycles, and
soil biological activity. It is based on minimal use of off-farm inputs and on

communities of

management practices that restore, maintain, or enhance ecological harmony. The

soil life, plants,

primary goal of organic agriculture is to optimize the health and productivity of

animals, and people.

interdependent communities of soil life, plants, animals, and people.” (NOSB, 2003)
Though the term “organic” is defined by law (see “Legal” section on pages 3
and 4), the terms “natural” and “eco-friendly” are not. Labels that contain those terms may imply some
organic methods were used in the production of the foodstuff but do not guarantee complete adherence to
organic practices as defined by a law. Some products marketed as “natural” may have been produced with
synthetic or manufactured products (those not
considered to be “organic”), such as “natural beef.”
While eco-labels are encouraged for producers
interested in lowering synthetic inputs and farming
with ecological principles in mind (biodiversity, soil
quality, biological pest control), eco-labels are not
regulated as strictly as USDA organic labels.

Products labeled as “organic” meet strict legal
requirements, including certification by a third party.

PM 1880 May 2003

Organic Agriculture

. . . the largest

U.S. Statistics

purchasers of

Organic agriculture is the oldest form of
The USDA reported on organic producorganic products
agriculture on earth. Farming without
tion statistics in the United States
the use of petroleum-based chemicals
(USDA-ERS, 2002). This census, conductare young people
(fertilizers and pesticides) was the sole
ed in 2002, identified U.S. farmers who
and college-educated
option for farmers until after World War
reported 2.5 million acres of land
II. The war brought with it technologies
dedicated to organic production. This
consumers.
that were useful to agricultural producfigure probably under-represents current
tion. For example, ammonium nitrate
production because many organic farmused for munitions during World War II
ers produce their products organically,
evolved into ammonium nitrate fer tilizer;
but sell less than $15,000 per year and are exempt
organophosphate nerve gas production led to the
from inspection (see “Organic Certification”), or do
not label their product as organic and, in general,
development of powerful insecticides. These technical advances since World War II have resulted in
are direct marketing to a local customer. In 1999,
significant economic benefits as well as environIowa farmers reported 150,000 acres of organic
mental and social detriments. Organic agriculture
cropland to the Iowa Department of Agriculture and
seeks to use those advances that consistently yield
Land Stewardship (IDALS) survey. This increase in
benefits, such as new varieties of crops, precision
organic acreage in Iowa represents a doubling from
agriculture technologies, and more efficient
the previous year and a sixfold increase since 1996.
The U.S. organic industry continues to grow at
machinery, while discarding those methods that
a rate of 20 percent annually. Industry estimates
have led to negative impacts on society and the
placed it at $10 billion in 2001. The organic industry
environment, such as pesticide pollution and insect
is a consumer-driven market. According to industry
pest resistance. Organic farming is considered a
surveys, the largest purchasers of organic products
systems approach, where interactions between
are young people and college-educated consumers.
components (crops, animals, insects, soil) are as
Today we are faced with the unique opportunity to
important as the whole farm itself.
Instead of using synthetic fertilizers, organic
take advantage of a growing market demand and
farmers use crop rotations, cover crops, and comuse the technologies developed over the past 50
post to maintain or enhance soil fertility. Also,
years. More and more farmers are interested in
instead of using synthetic pesticides, organic
the profitability and environmental benefits that
farmers employ biological, cultural, and physical
organic systems yield.
methods to limit pest expansion and increase
populations of beneficial insects. Geneticallymodified organisms (GMOs), such as herbicideresistant seeds and plants, as well as product
ingredients, such as GM-lecithin, are disallowed in
organic agriculture because they constitute
synthetic inputs and pose unknown risks (see GMO
discussion opposite).
In 2001, there were 2.3 million
acres in organic production in
the United States.

WASHINGTON STATE UNIVERSITY

History

World Statistics

Worldwide consumption of organic products has
experienced tremendous growth, often surpassing
the U.S. figures of 20 percent annual gain. Much of
the increase in worldwide consumption has been
fueled by consumers’ demand for GMO-free
products. Because GMOs are disallowed in organic
production and processing, organic products automatically are designated as GMO-free at the
marketplace. European consumers have led the
demand for organic products, particularly in countries such as the Netherlands, Italy, and Austria.
Two percent of all German farmland, four percent of
Italian farmland, and 10 percent of Austrian farmland is managed organically. Prince Charles of
England has developed a model organic farm and
has established a system of government support for
farmers making the transition to organic production. Major supermarket chains and restaurants in
Europe and the United States offer a wide variety of
organic products in their aisles and on their menus.

Organic produce has become a more visible menu item at
restaurants around the world.

through conservation of food and nesting sites.
Others import their fertility and pest management
inputs. The philosophy of “input substitution” is
discredited by many longtime advocates of organic
agriculture. A truly sustainable method of organic
farming would seek to eliminate, as much as possible, reliance on external inputs.

Organic Certification—
Legalities and Logistics

Philosophy

The motivations for organic production include
The motivations for
concerns about the econoorganic production
my, the environment, and
food safety. Although all
include concerns
organic farmers avoid
about the economy,
synthetic chemicals in
their operations, they difthe environment,
fer in how they achieve
and food safety.
the ideal system. Organic
farmers span the spectrum: some completely
eschew external inputs
and create on-farm sources of compost for fertilization and encourage the activity of beneficial insects

When Congress passed the Organic Food
Production Act (OFPA) in 1990, it was heralded by
many as the first U.S. law to regulate a system of
farming. This law can be accessed at the Web site
http://www.ams.usda.gov/nop/. OFPA requires
that anyone selling products as “organic” must
follow a set of prescribed practices that includes
avoiding synthetic chemicals in crop and livestock
production and in the manufacturing of processed
products. Organic certification agencies were
established in the United States to provide the
required third-party certification. Some states,
including Iowa, followed suit and established their
own organic laws. In 1990 Iowa passed Chapter 190,

Organic Agriculture

adopting the definition of
organic as prescribed in
OFPA and establishing
. . . all farmers
penalties for producers
falsely identifying their
are encouraged
products as organic. Iowa
to join a
allows private certification
agencies to operate in
certifying association
addition to its own certifiand a network
cation program. This
system is in contrast to
of organic farmers.
that of California, for
example, which relies on a
private certifier, California
Certified Organic Farmers
(CCOF), and that of Washington, which requires all
farmers to be certified through the state. Inspection
fees average $250 per year per farm to support the
independent inspection structure. Additional fees
are based on sales or individual acreage, depending
upon the agency.
After seven years of revisions, proposed rules
implementing the federal OFPA law were promulgated in 1997. However, these rules were revised
and released in 2001. Federal rules require that all
farmers who gross more than $5,000 per year from
organic sales be certified through an agency
accredited with the USDA’s National Organic
Program (NOP). The small farmer exemption allows
small-scale producers to receive the benefits of
premium prices (provided produce is raised organically) while avoiding certification fees. This
allowance may change in the future, however, and
all farmers are encouraged to join a certifying
association and a network of organic farmers.

OCIA Chapter Three–Southeast Iowa
319-592-3266
OCIA Chapter Four–Northeast Iowa
641-435-2156
Farm Verified Organic, North Dakota
701-486-3578
Quality Assurance International (QAI)
San Diego
858-792-3531
California Certified Organic Farmers (CCOF)
831-423-2263
Oregon Tilth
503-378-0690

Organic Labels

In October 2002, the USDA began enforcing a set of
national standards that food labeled “organic” must
meet, whether it is grown in the United States or
imported from other countries. The use of the seal is
voluntary, so some organic food products may not
carry the new label, but all organic products will
carry notification of third-party certification.
Under the new standards, before a food can be
labeled as organic, a government-approved certifier
must inspect the farm where it is grown to ensure
that it was raised according to USDA organic
standards. In addition, companies that handle or
process food labeled organic must be certified.
The standards permit four different types of
organic labeling. Foods labeled “100 percent
Organic” must contain 100 percent organically
produced ingredients. Products labeled “Organic”
must contain at least 95 percent organic ingredients. Packages that state, “Made with Organic Ingredients” must contain at least 70 percent organic
ingredients. Packages that claim their products
have some organic ingredients may contain
more than 30 percent of conventionally produced
agricultural ingredients and/or other substances.

Certification Agencies Practicing in Iowa
Organic Crop Improvement Association (OCIA)
Lincoln, Nebraska
402-477-2323
OCIA Chapter One–Central/Western Iowa
712-367-2442
OCIA Chapter Two–Northeast Iowa
507-583-4581
P

organics every other year.
For more infor mation,
contact Kathleen Delate,
assistant professor in
the departments of horticulture and agronomy, 106
Horticulture Hall, Ames,
Iowa 50011, by telephone
at 515-294-7069, by FAX at
515-294-0730, or by e-mail
at kdelate@iastate.edu.

The new USDA organic
label appears on all
certified products in
the U.S.

Required Certification
Practices for Crops

as “organic” the
crop must have been
raised on land that
no synthetic chemical
(including fertilizers,
herbicides, insecticides,
or fungicides) inputs

To sell a product as
were applied for
“organic” the crop must
have been raised on land
three years prior
that no synthetic chemical
to harvest.
(including fertilizers, herbicides, insecticides, or
fungicides) inputs were
applied for three years
prior to its harvest. In addition, no GMO crops (e.g.,
Roundup-Ready ® soybeans and Bt-corn ®) are
allowed in organic production.
Split operations, which means conventional and
organic fields are located on the same farm, are
allowed by Iowa law, but they require special care.
For example, a border of 25 feet is recommended
between organic and conventional fields in mixed
operations (see “Organic Soybean Production”
section on page 10).
Only naturally occurring materials are allowed
in production and processing operations, and all
treatments must be noted in farm records.
A crop rotation plan must be in place to protect
against pest problems and to maintain soil health.
Row crops should be raised for no more than four
out of five years, and the same row crop cannot be
grown in consecutive years on the same land.
Legumes (e.g., alfalfa, red clover, berseem clover,
and hairy vetch) alone, or in combination with small
grains (e.g., wheat, oats, and barley), should be
rotated with row crops (corn, soybeans, amaranth,

Added water and salt are not counted as organic
ingredients. The use of the USDA Organic Seal can
only be used on the 95% and 100% organic products.
For more detailed information about the USDA
organic labeling requirements or information on
how to become certified organic, visit the following
Web sites:
http://extension.agron.iastate.edu/organicag/
www.ams.usda.gov/nop/Consumers/brochure.html
www.ams.usda.gov/nop/NOP/NOPhome.html

State of Iowa Organic Certification Program
IDALS began offering a state certification program
in March 2000. Farmers may elect to use the state
program in place of or in conjunction with a private
certification agency. The state program will use
similar rules and fee structures as private
certification agencies operating in Iowa. For more
information, contact Maury Wills, IDALS Organic
Program, by telephone at 515-281-5783.

Iowa State University
Organic Agriculture Program
Iowa State University operates the Organic
Agriculture Program (OAP) to provide research
information and extension presentations for
Iowans. OAP holds field days, workshops, and an
Iowa Communications Network (ICN) series on

To sell a product

K. DELATE

Organic Agriculture

Organic crops are required to be grown in rotations, as
demonstrated by the corn-soybean-oat-alfalfa rotation,
shown at the I.S.U. Neely-Kinyon Farm.

Organic livestock must be fed 100 percent organic feed
and hay.

order to be certified organic. Alternative
and vegetables) to ensure a healthy
health therapies, such as botanical
system (see “Soil Health” section, page
remedies and muscle manipulation, are
9). A typical six-year rotation in Iowa is
The first step
used by some organic livestock produccorn (with a cover of winter rye)ers. Organic cows must be raised as
soybeans-oats (with an underseeding of
in making the
organic (following prior specifications)
alfalfa)-alfalfa-corn-soybeans. Horticultransition to certified
in the final trimester in order to sell
tural crops should be rotated with a
calves as “organic.” Supplements
leguminous cover crop at least once
organic production
(vitamins, minerals) must be approved
every five years to enhance soil quality.
is contacting a
by your certification agency and must
Organic production specifically
not be listed as Prohibited Substances of
prohibits certain practices, such as the
certification agency.
the National List (www.ams.usda.gov/use of biosolids, or sewage sludge, due
nop/NationalList/ListHome.html).
to concerns about bacterial and heavy
metal contamination. Irradiated products
First Steps to Certification
also are prohibited because irradiated elements do
The first step in becoming certified for organic
not occur in nature. Examples of products used in
production is contacting a certification agency. By
organic crop production are described in the
joining a local organic certification association,
“Examples from the Field” on page 10.
organic farmers may participate in various meetings,
field days, and visits to organic farms. Certain
Required Certification Practices for Livestock
sections of land can be converted (such as CRP)
Purchasing (or raising your own) parasite-free,
immediately into certified organic status if no synorganically-raised stock and providing access to
thetic chemicals (including Round-Up® and fertilizers)
ample pasture, water, and nutritional feed should
have been applied for the previous three years.
allow for healthy organic livestock production.
During the three-year transition to certified
Livestock must receive 100 percent organic feed.
organic production, records should be kept on all
Synthetic hormones and antibiotics are not permitsubstances applied to the land. An inspector will
ted; however, the natural bacteria present in
visit the farm in the third year (or the year the
vaccinations is permissible. Synthetic parasiticides
farmer anticipates selling his or her crop as organic)
are not allowed; instead, organic farmers rely on
and review all records, crops, storage bins, and
natural parasiticides, such as diatomaceous earth
equipment used on the farm to assure compliance
(DE). Livestock must have access to pasture in
P

with organic standards. The farmer will be issued a
certificate upon completion of inspection and
approval by the certification board. Certification
fees are based on an inspection fee (average cost is
$250/year) and anticipated acreage/livestock
costs (average total fees are $3/acre).

J. DEWITT

Marketing

Although the organic
industry began as a niche
Although the
market, steady growth has
organic industry
led to its place as a segment market since 1997.
began as a
The organic dairy industry
niche market,
expanded by 73 percent
from 1996 to 1997 and consteady growth
tinues to grow. Organic
has led to its place
markets can be divided
into indirect and direct
as a segment market
markets. Indirect or wholesince 1997.
sale markets include cooperatives, wholesale produce
operations, brokers, and
local milling operations for organic grains (see
companies listed on page 14). Many supermarket
chains buy directly from farmers (organic certificates are required) or from wholesalers of organic
products. Because meat now can be labeled as
organic, the marketing of organic beef, pork,
chicken, and lamb has been simplified significantly.
Roadside stands, farmers markets, and community supported agriculture farms (CSAs) constitute
the direct marketing end of the organic industry.
There are approximately 1,000 CSAs across the
United States. In CSAs, clients support a farm’s
production by purchasing a share, which can range
from $200 to $400/season. For each share, clients
receive an average of 15 pounds of produce per
week. For more information on CSAs, see the Iowa
State University Extension publication on Iowa
CSA Farms (PM 1693).

Farmers markets offer opportunities for small- and largescale operations.

Premium Prices
According to the Organic Alliance (www.organicalliance.org), organic premiums range from 20
percent to 400 percent above conventional prices,
depending on the season and availability of the
product. As an example, premium prices for organic
carrots have ranged from 27 percent in the summer
growing season to 200 percent in the winter
months. Most consumers relate their willingness
to pay premium prices for food raised without
synthetic chemicals to their concerns about food
safety and the environment.

Subsidies
Although many European countries financially
support their farmers’ organic production practices,
the United States has made small gains in this area.
In Iowa, the Natural Resources Conservation
Services (NRCS) offers organic farmers $50/acre
during their transition to organic farming through
the Environmental Quality Indicators Program
(EQIP). and through the new organic cost-share
programs with the 2002 Farm Bill. Check with
local NRCS or FSA offices regarding deadlines and
required documents. Other conservation practices
used on organic farms (e.g., riparian buffer strips,
filter strips, and crop rotations) also may qualify for
cost sharing.

Organic Agriculture

The basis for all organic
farming systems is the
health of the soil.

Composting, the preferred method of stabilizing
manure, is a controlled
Organic farmers
process in which nitrogencontaining materials are
strive to maintain
mixed with a carbon-conadequate fertility as
taining source to produce
a substance preferably in a
well as biologically
carbon-to-nitrogen ratio
active soil with the
(C:N) of 30 to 1. Compost
temperatures must reach
microbial populations
131–170°F for 15 days, and
required for
be turned a minimum of 5
times to aerate the pile.
nutrient cycling.
Additional information on
composting practices is
listed in the references.
Though many soil amendments are available
for organic farming, these materials must be naturally based. In addition to manure-based fertilizers,
many organic farmers rely on fish emulsion and
seaweed preparations to supply nitrogen and other

Soil Health:
The Basis for Organic Farming

Organic farmers strive to maintain adequate
fertility as well as biologically active soil with the
microbial populations required for nutrient cycling.
Crop rotation provides nutrients such as nitrogen
from legume crops and carbonaceous biomass upon
which beneficial soil microorganisms depend for
survival. Naturally mined lime products, manure,
and composted manure are the most common forms
of soil amendments for organic operations. Iowa
rules specify the number of months prior to harvest
that manure should be applied to allow adequate
decomposition and to avoid bacterial contamination
of produce. Manure cannot be applied for a
minimum of four months prior to the harvest of
horticultural crops and for three months prior to
agronomic crop harvest. Raw manure cannot be
applied to frozen or snow-covered ground.

K. HAGEN

K. DELATE

In trials at Iowa State University, organic peppers fertilized
with compost produced equivalent yields compared with
non-fertilized plants.

Green lacewings are prominent predators on organic farms
in Iowa.

elements. When phosphorus and potassium limit
crop production, rock phosphate and naturally mined
potassium chloride are allowed. It is imperative
that organic farmers check with their certification
agencies before applying any materials. Certification
may be revoked for up to three years if a material
contaminated with prohibited materials is applied.

commercial preparations
of natural insect pathogens, such as Bacillus
The basis of insect,
thuringiensis (Bt), which
are used to manage
disease, and
pestiferous larvae such as
nematode management
corn borers.
Botanical insecticides,
in organic farming
such as neem and ryania,
systems is the
also are allowed in organic
production, but as with all
reliance on the
insecticides, they should
inherent equilibrium
be used only as a last
resort. Although these
in nature.
materials are naturally
based, some materials may
affect natural enemies.
Prevention is a cornerstone of organic farming.
Only pest-free seeds and transplants should be
brought onto organic farms. Physical and cultural
methods are used to prevent pest infestations.
Physical methods include the use of row covers for
protection against insects, such as cabbage
butterflies and aphids. Cultural methods include
sanitation (destroying all infested plant material
at season’s end) and resistant varieties. The
varieties used in organic farming have been bred
traditionally (i.e., no manipulated gene insertion
or engineering involved) for insect, disease, and
nematode resistance or tolerance.

Pest Management:
Working with Nature

The basis of insect, disease, and nematode management in organic farming systems is the reliance
on the inherent equilibrium in nature. Most insect
pests have natural enemies to keep their populations in check. Natural enemies include insect
predators (insects that consume part or all of pest
insects), parasites (insects that use other insects to
produce their offspring, thereby killing the pest
insect in the process), and pathogens (diseases
that kill or decrease the growth rate of insect
pests). Predatory insects on organic farms include
lady beetles, lacewings, and spiders. Parasitic
insects include wasps and flies that lay their eggs
in/on pest insects, such as larvae or caterpillars.
Beneficial insects exist naturally on farms, or
they can be purchased from commercial insectaries
and released seasonally. Also available are

Organic Agriculture

K. DELATE

cultivation, particularly during times of high field
moisture. Mulching with straw or wood chips is a
common practice in many horticultural operations.
Mulch from organic farms is preferred to avoid any
possibility of pesticide residues from conventional
materials. If organic sources are not available,
turning the mulch pile for several weeks prior to
application is recommended (follow composting
practices). Allelopathic crops, such as rye and oats,
exude a chemical that mitigates against weed
establishment and seedling vigor and are
recommended between corn and soybean crops.

Propane flame burners can be used on organic farms to
control weeds between and within rows.

Weed Management:
Multiple Tactics Work Best
Examples from the Field:
Organic Soybean Production
Most organic farmers

Preplanting and Seed Selection

rely on multiple

Organic soybeans were grown on approximately
60,000 acres in Iowa in 1998. Though the market
remains strong for organic soybeans, determining
your market should occur before any acreage is
planned. Buyers will help determine the varieties
their organic farmers should grow based on their
needs. A list of some of the buyers operating in
Iowa is included on page 14. All organic soybean
varieties are bred for the food-based tofu or natto
market (e.g., specific seed size and protein
requirements).
The ideal crop preceding soybeans is winter
rye, an allelopathic crop, to help prevent weed
establishment. In the spring, rye that is less than 8
inches in height can be killed with a field cultivator.
If plants are taller, rye should be mowed or cut with
a stalk chopper before cultivating or disking to kill
the rye. A second cultivation may be necessary if
there are any remaining rye plants.
Fall soil sampling will help determine if soil is
adequate for soybean production. Adjustments to a

tactics for their
weed management.
Allelopathic crops,
cultivation, mulching,
and flame burning
are methods available
to organic farmers.

Organic strawberries are commonly mulched with
straw to prevent weeds and disease, aid in moisture
retention and keep fruits free of soil particles.

J. DEWITT

Most organic farmers rely
on multiple tactics for their
weed management. Allelopathic crops, cultivation,
mulching, and flame burning are methods available
to organic farmers. Depending on the crop, cultivation
offers the least laborintensive method of weed
management. Timely cultivation is key; weeds will
proliferate without specific
schedules. Propane flame
burning is generally used
in conjunction with

K. DELATE

Many organic farmers plant a cover crop of winter rye on
ridges prior to their soybean crop to assist in erosion and
weed prevention.

Rotary hoes or harrows are the first tillage operation used
on organic farms.

Pest Management

K. DELATE

Weed management is key
to a successful organic
Weed management
crop. Three to five days
is key to
after planting, fields are
rotar y-hoed at a slow
a successful
speed (5 mph) to kill weeds
organic crop.
in their initial germination
or white-thread stage. A
harrow also can be used at
this stage. One week later,
after soybeans have emerged, fields are hoed again
at a faster speed (7–9 mph). Two- to three-row
cultivations are a normal practice. The first cultivation is at a slow speed, as soon as rotary-hoeing
ends. The second cultivation is at mid-season at a
faster speed to throw about one inch of soil around
the base of plants. The third cultivation is at a slow
speed (5 mph).
Various attachments and plant protection
devices can be added to cultivators (see the
reference Steel in the Field, produced by the USDA
Sustainable Agriculture and Research Education
[SARE] Sustainable Agriculture Network, available
from Iowa State University).
Insects generally do not cause yield loss in
organic soybeans. Occasional browsing by grasshoppers, leafhoppers, and bean leaf beetles rarely

Row cultivators are used two to three times to control
weeds between rows.

proper soil pH of 6.5 to 7.0 can be made through
applications of lime in the fall or spring (usually
Iowa soils do not require dolomitic lime). Phosphorus
may also be required and can be supplied through
composted manure or rock powders. Seeds are
planted when the soil is adequately warmed for
this tropical crop (usually around May 15), 1 inch
deep, in a planting population ranging from 175,000
to 225,000 seeds/acre (depending on the variety).
Seeds normally are planted in 30 or 36 inch rows,
depending on planting/cultivating equipment
specifications. Seeds planted in narrower rows
have been attempted, but currently, the most
economical method of weed management requires
cultivators, which usually cannot fit narrow rows.

surpasses economic threshold levels.
If any GMO seeds are found in
If any GMO seeds
An issue of growing importance, howorganic lots, the entire field can be
ever, is the relationship between the
rejected for organic certification. Certain
are found in
bean leaf beetle and a host of soybean
specifications in combine settings must
organic lots,
seed diseases.
be followed in order to prevent any
Because the majority of organic
soil from contaminating the edible
the entire field
soybeans are destined for the edible tofu
beans. Smooth plates, dual rotating
can be rejected for
market, a white seed color is required.
screens, and slower speeds are used to
Soybeans will enter the organic feed
avoid splitting seeds and lowering seed
organic certification.
market at a reduced price if there is
quality. Seed moisture also is a concern;
seeds should be harvested at full size
purple, brown, or tan staining from
from 16–13 percent moisture to avoid
Cercospora, Fusarium, soybean mosaic
cracking or shriveling in the case of immaturity.
virus, or bean pod mottle virus, transmitted by the
Because soybeans may not be sent to market
bean leaf beetle. Although certain varieties appear
for periods ranging from one week to six months
to resist staining, high rainfall during pod set may
(depending on the buyer’s scheduling), storage
create ideal conditions for the spread of the disease
facilities are necessary. Again, separate storage
in any variety. Soybean cyst nematode has not been
facilities for conventional and organic crops are
found to be a problem on organic farms. Several
required. Proper seed moisture content should
factors, including crop rotations and chemical exudates from crop residues and manure applications,
prevent the need for additional drying, but fans and
may mitigate against nematode survival. Soil samdrying facilities should be used to adjust for
pling two weeks prior to harvest is recommended to
seasonal differences. Diatomaceous earth (DE) can
determine any possible nematode introductions.
be mixed in storage bins to prevent insect contamination. This substance is nontoxic to humans but
Non-GMO SCN-resistant varieties can be used if
damages the exoskeleton of insects and causes
infestations are detected.
death. Moldy or “buggy” soybeans will be rejected.
Harvesting and Storage
Many buyers require a sample of soybeans prior
Harvesting and storage of organic soybeans repreto accepting a load. Soybeans will be screened
sent the final key areas of concern in garnering
premium prices. The contract will dictate the
desired seed size, moisture content, and cleanliness
of the soybean harvest. Certain weed seeds, such
as nightshade, can stain soybeans and must be
weeded from fields prior to harvest. In general,
organic farmers plan for one hour of hand-weeding,
or walking, for every acre of soybeans.
It is imperative that separate combines are
used for organic and conventional fields or combines
undergo a thorough cleaning (a minimum of two
hours) between conventional and organic fields.
Iowa State University has a video describing the
combine clean-out procedures (Combine Clean-Out
Harvesting and storing organic soybeans are important
Procedures for Identity-Preserved Grains, EDC-255).
steps in collecting a premium price.

USDA NATURAL RESOURCES CONSERVATION SERVICE

Organic Agriculture

the nutrition of the tofu or natto, but it can affect the
texture and color.

based on size and will be tested for GMO contamination. Most buyers allow a certain percentage of
“clean-out” (generally less than 15 percent).
Screened beans (small sized or split seeds) can
enter the organic livestock feed market. Stained
beans either can enter the organic livestock market
or be blended into other clean streams (if less than
3 percent are stained). The staining does not affect

Economics
Cost-of-production studies for organic and conventional tofu soybeans are presented in Tables 1 and 2.
Costs for 1998 represent actual costs incurred
at the Iowa State University Neely-Kinyon Farm.

Table 1

Comparison of Organic and Conventional Clear-Hilum Soybean Economic Analysis, Greenfield, 1998
Production Costs
(actual cost per acre)
Moldboard plowing

Organic

Conventional

$8.10

Disking

4.00

Field cultivation (preplant)

4.00

Fertilization

Planting

9.00

31.60

22.00

Seed
Herbicide

10.38

Sprayer

2.50

Rotary hoeing (2x)

4.00

Row cultivating (2x)

7.00

Hand-weeding

14.00

Combining

21.00

0
(FOB per contract)

3.00

Hauling grain to market
Total cost per acre
Returns

$102.70

$108.98

$850.00
50 bu/A x $17.00/bu

$312.00
48 bu/A x $6.50/bu

Profit per acre

$747.30
Excluding price of land

$203.02
Excluding price of land

Organic profit

368%

Table 2

Estimated Economic Analysis, Adjusting for On-Farm Costs in 1999
Production Costs
(per acre)

Organic

Land

$100

Certification fees
1999 Total costs per acre
1999 Returns
1999 Profit/acre

Conventional
$100

$15

$217.70

$208.98

$700
$14/bu x 50 bu/A

$300
$6/bu x 50 bu/A

$482.30

$91.02

Organic Agriculture

Iowa State found that projected costs of production
for similar operations were
Soybeans currently
comparable in 1998. Selling
price for organic crops
are the most lucrative
represented 1998 prices
crop in the system,
(free on board [F.O.B.] or
pick-up on the farm). Prices
but new markets for
also reflect the obtainable
non-GMO crops and
price for certified organic
crops or crops grown on
alternative crops,
land without synthetic
such as organic
chemicals for three years
prior to harvest. Transition
dry beans,
soybeans were sold for
hay/silage/grain for
$10 per bushel in 1998, but
because of the availability
organic dairies and
of organic soybeans in
equestrian centers,
1999, there were limited
markets for transitional
and medicinal/culinary
soybeans. Selling price for
herbs, continue
organic soybeans in 1999
averaged $14 per bushel.
to grow.
Averaging across all crops
in a typical rotation for
certified organic systems,
Iowa State University research demonstrated a
return of $300/acre. Soybeans currently are the
most lucrative crop in the system, but new markets
for non-GMO crops and alternative crops, such as
organic dry beans, hay/silage/grain for organic
dairies and equestrian centers, and medicinal/
culinary herbs, continue to grow.

Profiseed International, Inc.
Hampton, IA
641-456-5955
Clarkson Grain
Beardstown, IL
217-323-2350, 800-252-1638
Dunn International
Waterloo, IA
319-233-5504
Pattison Brothers
Fayette, IA
800-632-5952
Stonebridge Limited
Cedar Falls, IA
319-27
Sunrich
Hope, MN
800-342-6976
Microsoy Corporation
Jefferson, IA
515-386-2100
Natural Products
Grinnell, IA
641-236-0852
Organic Valley/CROPP
(Coulee Region Organic Produce Pool)
LaFarge, WI
608-625-2602

Buyers of Organic Grains, Produce,
and Livestock
Heartland Organic Marketing Cooperative
Stuart, IA
515-523-1888
Pacific Soybean and Grain
San Francisco, CA
415-433-0867

moth, and leaf-eating larvae
(caterpillars). Codling moth
management includes
pheromone traps or ties
Organic apple
placed on branches, which
production represents
emit a chemical that disrupts the mating ability of
one of the most
the codling moth and leads
intensively managed
to lower insect populations. The plum curculio
organic systems.
beetle can be controlled
through physical means:
teams of workers displace
beetles by tapping trees
with baseball bats or sticks wrapped in cotton cloth.
Beetles drop from trees onto squares of white
sheets placed under trees to be collected and
burned or buried. Apple maggot flies are managed
through the use of Stickem®-coated plastic red balls
resembling apples. Adult flies cue in on the shape of
the ball and attempt to oviposit eggs. Kaolin clay
sprays, have proven successful in mitigating egg
laying from the codling moth and plum curculio.
This clay-based spray has been reported to lower
plant pathogens affecting apple leaves, but our
research has shown only insect control due to low
disease pressure in our trials (Friedrich et al., 2003).
Weeds are managed in tree middles by mowing
ground covers, usually a mix of grass and legumes.
Specialized mowers are available with articulated
hydraulic arms to mow between trees within rows.
Some growers use Weed Badgers® to cultivate
around trees, but caution must be used to avoid
damage to trees and root systems. Protection from
deer browsing can include perimeter fencing and/or
individual cages when trees are young. Many
growers employ alarms or dogs within their
orchards to prevent deer attacks.
Marketing of organic apples can occur through
several channels—on-farm sales, CSAs, or directly
to stores. Stores will require proof of organic certification if you wish to sell your fruit as “organic.”

Examples from the Field:
Organic Apple Production

K. DELATE

Organic apple production represents one of the
most intensively managed organic systems.
Because scab is the most destructive disease of
apples in Iowa, it is imperative that growers select
disease-resistant varieties suitable for this state.
Iowa State University has tested the following
varieties and found them to be suitable: Jonafree,
Redfree, Liberty, Freedom, Dayton, William’s Pride,
Gold Rush, Enterprise, Priscilla, and Nova Easygro.
Trees should be purchased from a reputable
nursery and should be free of diseases and insects.
Graft marks should be well above where trees will
be placed (even with the soil surface). Trees should
be planted in the spring after threat of frost has
passed. Today, most growers are planting on dwarf
or semi-dwarfing root stocks. Trees can be trellised
or planted in normal rows. Apple blossom thinning
to increase size of harvested fruits is normally
conducted by hand, but natural sprays are being
used in large, commercial orchards in other parts of
the country.
Pest management in apple orchards includes
control of the plum curculio, apple maggot, codling

Unblemished organic apples can be grown when growers
employ rigorous pest management practices.

Organic Agriculture

References
Bowman, G. (ed.). 1997. Steel in the Field—A farmer’s

IDALS (Iowa Department of Agriculture and Land

guide to weed management tools. Sustainable

Stewardship). 2000. Iowa Organic Certification and

Agriculture Network, USDA, National Agriculture

Organic Standards. Des Moines, IA.

Library, Beltsville, MD.

NOSB (National Organic Standards Board), USDA-NOP,
http://www.ams.usda.gov/nop/.

Delate, K., C. Cambardella, K. Taylor, and B. Burcham.
1999. Comparison of organic and conventional rota-

Rynk, R. 1992. On-Farm Composting Handbook. NRAES-

tions at the Neely-Kinyon Long-Term Agroecological

54. Northeast Regional Agricultural Engineering

Research (LTAR) site: First year results. Leopold

Service. Ithaca, NY.

Center for Sustainable Agriculture Annual Report,

Sustainable Agriculture Network (SAN). 1998. Managing

Iowa State University, Ames, IA.

cover crops profitably. 2nd Edition. Sustainable

Friedrich, H., K. Delate, P. Domoto, G. Nonnecke and

Agriculture Network, USDA National Agriculture

L. Wilson. 2003. Effect of organic pest management

Library, Beltsville, MD.

practices on apple productivity and apple food safety.

USDA-ERS (Economic Research Service), www.ers.usda.-

Biological Agriculture and Horticulture 21: 1–14.

LEOPOLD CENTER

gov/Data/organic.

This research project is partially funded by the
Leopold Center for Sustainable Agriculture at
Iowa State University and the USDA-IFAFS
Organic Agriculture Consortium.

File: Agriculture 2

[C]

. . . and justice for all
The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, gender, religion,
age, disability, political beliefs, sexual orientation, and marital or family status.
(Not all prohibited bases apply to all programs.) Many materials can be made
available in alternative formats for ADA clients. To file a complaint of discrimination, write USDA, Office of Civil Rights, Room 326-W, Whitten Building, 14th and
Independence Avenue SW, Washington, DC 20250-9410 or call 202-720-5964.

Prepared by Kathleen Delate, Iowa State University.
Edited by Jean McGuire, ISU Extension
Continuing Education & Communication Services.

Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30,
1914, in cooperation with the U.S. Department of Agriculture. Stanley R. Johnson,
director, Cooperative Extension Service, Iowa State University of Science and
Technology, Ames, Iowa.

Illustrated by Jane Lenahan.
Designed by Mary Sailer, Spring Valley Studio.
Soil Web graphic on page 8 reprinted with permission from
Soil and Water Conservation Society (SWCS). 2000. Soil
Biology Primer. Rev. ed. Ankeny, Iowa: Soil and Water
Conservation Society.
Some photos on the cover were provided courtesy of Iowa
State University College of Agriculture and the USDA NRCS.
For the latest on organic agriculture from Iowa State University
go to http://extension.agron.iastate.edu/organicag/.