June 16, 2005:
As you are planting your fields this season, pay attention to what
your neighbors are planting as well. How are they managing their
land? Be mindful of where they are using chemical fertilizers, pesticides,
and other prohibited substances, since their practices will largely
determine where you need to maintain buffers.
During the inspection for organic certification, the inspector
reviews your management of buffers to insure they minimize the risks
of contamination for your organic crops. Appropriate buffers must
also be maintained in pastures and outdoor access areas used for
organic livestock, if needed.
One of the requirements for organic certification is to have “distinct,
defined boundaries and buffer zones such as run-off diversions to
prevent the unintended application of a prohibited substance to
the crop or contact with a prohibited substance applied to adjoining
land that is not under organic management.” 
A buffer zone is defined as “an area located between a certified
production operation or portion of a production operation and an
adjacent land area that is not maintained under organic management.
A buffer zone must be sufficient in size or other features (e.g.,
windbreaks or a diversion ditch) to prevent the possibility of unintended
contact by prohibited substances applied to adjacent land areas
with an area that is part of a certified operation.” 
In other words, you need to maintain buffer zones along field borders
where your neighbors apply synthetic chemicals (or other prohibited
substances). This includes farm fields, conservation areas, residences,
and commercial operations.
The federal rule does not specify that a buffer zone be a specific
width, but 25 to 30 feet is generally accepted by certifying agents
as adequate to prevent most contamination from a neighboring field.
Buffer zones can be planted to a crop that is managed organically
but is sold as conventional.
A buffer can be planted to grass, or better yet, a permanent tree
and shrub planting, which can provide habitat for birds, wildlife,
and beneficial insects. Significant height in a buffer has the added
benefit of protecting your fields and organic crops from contamination
by aerial movement of pesticides and from wind erosion.
If you choose to plant your buffer to a crop, the crop is treated
as conventional. If sold, you must keep a record of the sale, such
as a weight ticket or invoice. Even if you allow your neighbor to
mow the buffer for hay, you must keep a written record of the hay
harvest (name, date, location of buffer and crop harvested). Certifying
agents can give you examples of buffer record forms. You can also
download an example of a buffer record from ATTRA’s website,
You should also mark all buffer zones on your farm map.
What about an area where your neighbor is not using prohibited
materials? Your certifying agent may require you to have your neighbor
sign a statement that they are not using prohibited substances in
areas adjoining your fields. Once you have written proof that no
prohibited substances are applied on adjoining land, the certifier
can grant you the option to raise organic crops without buffer zones
in affected areas.