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Home  > Question of the Week

Question of the Week

Permalink Where can I find information about fencing for sheep and goats?


Answer: Several articles discuss the various options for fencing for sheep and goats. A few of these articles discuss the costs of the various types of fencing. In addition there is a book, Fences for Pasture & Garden, that you may be interested in. This is a very thorough book about various types and set-ups for fence.


Fences for Pasture & Garden. Storey Publishing. 1 p.

McNally, J. 2004. Sheep fencing: more is usually better. Graze, Vol. 11, No. 9. pg. 14-15.

Zweede-Tucker, Y. 1997. How to Hotwire a Goat. Cashmirror, Vol. 9, No. 2. pg. 19-21.

OBrien, A. 2003. Fencing Options in Predator Control. The Shepherd's Journal, Vol. 10, No. 2. pg. 25-26.

Damerow, G. 1992. Electric fences reduce goat escapes to zero. Dairy Goat Journal, Vol. 70, No. 3. pg. 24.

Mitchell, E. 1994. Controlling Goats with the Right Fence. The Stockman Grassfarmer, Vol. 51, No. 11. pg. 30.

Damerow, G. 1993. Secrets for solving fencing woes. Dairy Goat Journal, Vol. 71, No. 2. pg. 16-17.

Fencing Systems. Pasture Talk, Vol. 6, No. 1. pg. 7, 9.

Barbour, P. 2001. Flexible fencing fit for grazing. Successful Farming, Vol. 99, No. 4. pg. 2.

Shepherd, W. 1996. How to Choose the Right Fence for the Right Job. ACRES USA, Vol. 26, No. 11. pg. 11.

Pratt, D. 1992. Electric Fence Design.



Permalink Is it safe to use manure on my vegetables?


Answer: In general, it is best not to use raw manure on leafy green vegetables that will be harvested 60 days or less prior to application. The National Organic Standards requires a 120 day window for application of raw manure to harvest time.

Composting the manure is an option that makes the manure safer to handle, and provides a more stable nutrient source. If the manure that you use comes with bedding, the correct Carbon to Nitrogen ratio would exist for developing compost on your farm. A great deal of information on composting is available through our Farm-Scale Composting Resource List.

The ATTRA publication Manures for Organic Crop Production discusses specific procedures required by the National Organic Program, and gives in-depth safe manure handling recommendations, as well.



Permalink Where can I find information on obtaining and saving non-GMO heirloom vegetable seeds?

South Carolina

A good place to learn more about heirloom seed production is the ATTRA publication Seed Production and Variety Development for Organic Systems.

ATTRA also offers an online database of seed sources for organic growers that includes a section on untreated, non-GMO, and open-pollinated seed. Visit the Organic Seed Suppliers Search.

Although there are no GMO vegetable seeds on the market at this time, trial plots are situated in some locations. Both GMO tomatoes and GMO potatoes have been developed for commercial producers, but not marketed. Transgenic research has focused on four U.S. crops—soybeans, corn, cotton, and canola. Derivatives from these major crops are found in many processed foods.

A good resource for seed saving is the latest edition of Seed to Seed, by Suzanne Ashworth. It can be ordered through the Web site of Seed Saver Publications, Vegetables such as beans, peas, and tomatoes—which are self-pollinated—are very good choices for the beginning seed saver, as their seed almost always remains true to type.

The Seed Savers Exchange publishes annually an extensive listing of heirloom varieties available from members.
Seed Savers Exchange
3094 North Winn Road
Decorah, IA 52101

Another organization for seed savers is the Southern Seed Legacy Project.
Southern Seed Legacy (SSL)
Department of Anthropology
250A Baldwin Hall
University of Georgia
Athens, GA 30602



Permalink Is special machinery needed for weeding and cultivation on organic farms?


Answer: Farmers and dairy producers, including organic farmers, use a wide variety of management practices and techniques for weed control. Synthetic herbicides are just one tool that conventional farmers use that organic farmers cannot. However, all farmers have many more management tools and strategies that can be used to prevent and control weeds. Many people think first of cultivation when they think about weed control on organic farms. For a review of cultivating tools and implements, guidance systems, and flame weeding equipment, the following book (also available in its entirety online) is a useful reference:

Steel in the Field; A Farmer’s Guide to Weed Management Tools
Edited by Greg Bowman. 1997. Sustainable Agriculture Network, National Agricultural Library, Beltsville, MD

A recent issue of ATTRAnews was dedicated to weed management. It also appears online.

Another useful Web site is: European Weed Research Society, Physical and Cultural Weed Controls. This multi-lingual site has excellent photos as well as a description of the use and application of each tool.

Below I have pasted in a section of the USDA’s National Organic Program (NOP) standards that include general guidelines for preventative pest management practices, and suggestions for approaches to weed control. These are important because they clearly show that cultivation is just one of several strategies for successful weed management.

§ 205.206 Crop pest, weed, and disease management practice standard.
(a) The producer must use management practices to prevent crop pests, weeds, and diseases including but not limited to:

(1) Crop rotation and soil and crop nutrient management practices, as provided for in §§ 205.203 and 205.205;
(2) Sanitation measures to remove disease vectors, weed seeds, and habitat for pest organisms; and
(3) Cultural practices that enhance crop health, including selection of plant species and varieties with regard to suitability to site-specific conditions and resistance to prevalent pests, weeds, and diseases.

(b) Pest problems may be controlled through mechanical or physical methods including but not limited to:

(1) Augmentation or introduction of predators or parasites of the pest species;
(2) Development of habitat for natural enemies of pests;
(3) Nonsynthetic controls such as lures, traps, and repellents.

(c) Weed problems may be controlled through:

(1) Mulching with fully biodegradable materials;
(2) Mowing;
(3) Livestock grazing;
(4) Hand weeding and mechanical cultivation;
(5) Flame, heat, or electrical means; or
(6) Plastic or other synthetic mulches: Provided, That, they are removed from the field at the end of the growing or harvest season.

Two ATTRA publications are also particularly relevant:

Principles of Sustainable Weed Management for Croplands
Thistle Control Alternatives

Thistles are often a problem in pasture settings on dairy farms.

ATTRA’s other current offering of publications on weed management are: Field Bindweed Control Alternatives; Alternative Control of Johnsongrass; Flame Weeding for Agronomic Crops; and Flame Weeding for Vegetable Crops.

Regarding organic compliance, please notice that that both of these publications include a section on least-toxic herbicides with specific materials mentioned. These publications are more that two years old, and the allowability of brand-name materials is subject to frequent change.

I strongly recommend that certified organic producers follow these steps for any material inputs they are considering for use (before use):

1) Become familiar with NOP regulations about materials. The regulatory text can be found at
See sections 205.105 and the National List of Allowed and Prohibited Substances in sections 205.600-606. These state that natural materials are allowed unless they are prohibited, and that synthetic materials are prohibited unless they are allowed. Lists 205.601 and 205.603 list Synthetic substances allowed for use in organic crop and livestock production respectively, and 206.602 and 205.604 list natural materials that are prohibited. List 205.605 lists Non-agricultural substances allowed for use in or on processes products labeled as “organic” or “made with organic…”; and 205.606 lists Non-organically produced agricultural products allowed as ingredients in products labeled as organic or made with organic ingredients. Each list is intended to be specific to its type of production, and several products include annotations that restrict or specify their uses (i.e. crop fertilizers, pest, disease or weed control; livestock feed, feed additive or supplement, disinfectant, medical treatment or topical use).

2) List every material you use or plan to use in your Organic System Plan (OSP) that you submit to your certifier. Include the identity and source, or brand name and manufacturer of every material.

3) Verify whether your organic certifier has a current list of approved brand name materials. Many use OMRI and WSDA lists, and some maintain their own lists in addition to these:

• The Organic Materials Review Institute (OMRI) Products List
In addition to the OMRI Products List of brand name materials, OMRI also publishes a Generic Materials List for subscribers, which is a very useful source of information to help interpret the NOP’s National List, to determine whether a material is natural and whether it is allowed for use in organic production. Inclusion on the OMRI list must be renewed every year. Some products may be listed one year and not the next. Reformulations (common in the industry) may render a product non-compliant, or possibly make it compliant. In some cases, producers will be required to document which lot number of a product they used in order to verify compliance. For the same reasons, producers should review and update their OSPs annually or as needed to verify current materials compliance.

While OMRI is a nonprofit organization that is not officially recognized by the NOP, their services facilitate understanding of the National List, and many certifiers use the OMRI lists as their own list of approved brand name materials.

• Washington State Department of Agriculture (WSDA) Brand Name Materials List
The WSDA list is also recognized as a valid list of approved brand name materials.

United States EPA has begun a labeling program with a seal for products that are allowed under the NOP standards for organic crop production. However, it is not yet widely used.

4) Check whether the material you are interested in using it is on an approved list of Generic or Brand Name materials. Please note: always use the most current information available. The Web sites (above) are best to verify any claim of listing. A very recent printed guide is next best. It is the producer’s responsibility to verify the truth of that statement by checking the current lists on the Web site.

5) If the material/product you are interested in using is not listed in an approved list, follow your certifier’s instructions to verify its allowability. For example, attach a product label with a list of all ingredients, including inert ingredients, or a letter from the manufacturer that provides information sufficient to verify and document that all ingredient are allowed.

6) Be sure every material and supporting documentation is in OSP that it is approved by your Certifier before you use it. Your certification depends on it!

7) Keep documentation of every input material purchase and application for 5 years.



Permalink What vaccinations are recommended for calves in an organic operation?


Answer: Vaccination against disease is an accepted practice in organic beef cattle production and is allowed under the National Organic Program rules section 205.603(a)(3) Biologics-Vaccines. Vaccination should complement other preventative health management practices, such as reducing stress, ensuring a balanced ration, and providing pasture as a significant portion of energy needs.

Some natural beef producers contest vaccination, and assert that providing for the development of natural immunity through farm biodiversification protects animals better than a vaccination regime. Vaccines are seen by these practitioners to bypass natural immunity. Regardless, vaccination is a tool that should be carefully considered by the producer and the veterinarian. Every producer should develop their vaccination program to address the risks of diseases endemic to one's region. Consult your veterinarian to determine the types of vaccines recommended for your area.



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