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What organic hay preservatives are available?

D.E.IllinoisAnswer: The Resource list below contains several publications and articles discussing various hay preservation methods. The only preservatives that might be approved as organic are acetic acid (vinegar) or bacterial inoculants. Several articles say apple cider vinegar is an alternative treatment, but is only half as effective as propionic acid as a preservative and requires twice as much for equal preservation. Bacterial inoculants may be allowed as long as no GMO bacteria are used or other restricted materials are included. The Maine Organic Farming and Gardening Association publication Raising Organic Livestock in Maine: MOFGA Accepted Health Practices, Products and Ingredients specifically calls propionic acid (preservative for forages) a PROHIBITED material on page 10.Vinegar as a preservative may be an option, but to be considered an animal feed it would need to be organic vinegar. As a crop additive it would not have to be organic vinegar. You will need to discuss the specific products with your certifier prior to their use. Remember, organic production practices and materials needs to be approved by your USDA approved, certifying agency and written into your organic system plan. Each certifying agency has different interpretations on approved control methods and materials. You should also check with your certifier with any questions.Please consider the following advice with respect to use of material inputs:a. List every material you use or plan to use in your Organic System Plan (OSP) that you submit to your certifier as required.b. Identify the source and/or manufacturer of every material.c. Attach a label with a list of all ingredients including inerts.d. If the manufacturer does not provide a complete list of ingredients for the product, check to see if it is on an approved list of Brand Name materials, such as OMRI or WSDA (see and Note: if someone says their product is OMRI listed or cites an article that states that they are, or even shows the OMRI seal on the packaging, beware. It is the producer’s responsibility to verify the truth of that statement by checking the current lists on the website. Inclusion on the list must be renewed every year. Products may be listed one year and not the next. Reformulations (common in the industry) may render a product non-compliant or possible 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. e. Be sure everything is in your OSP and that it is approved by your Certifier before you use it. Your certification depends on it!f. Keep documentation of every input material purchase and application for 5 years.Resources:Anon. 2006. Raising organic livestock in Maine: MOFGA accepted health practices, products and ingredients. January. 14 p. 2006. The breakdown on hay preservatives and additives. Manitoba Agriculture, Food and Rural Initiatives. February. 9 p., Antony Meyer. 1996. Hay types for performance horses. 7 p., Mike. 2000. Preserving baled hay with organic acids. Focus on Forage. 2 p., Dan. 1999. Hay dessicants and preservatives. 2 p., Christy. 2005. Frequently asked questions ? Hay preservatives. Saskatchewan Agriculture and Food. 2 p.