Why Horn Manure Works

Italy. An informative study on Preparation 500.1

In a study published this year, Italian scientists described the benefits of the biodynamic production and application of horn manure, also known as Preparation 500. The study focuses on the microbiological transformation process of the manure, which takes place over a six-month period while the horn is buried in the ground. The study particularly emphasizes the horn’s role in this process. The researchers conclude that horn manure exhibits a much higher number of beneficial bacteria compared to open-air manure. At the same time, Preparation 500 favors the spread of an important fungus, Onygenales, precisely because of the keratin-containing horn. This creates an environment that attracts certain soil bacteria. As a result, horn manure contains a special microbiological composition that normally only occurs in fertile, uncultivated soil. The study provides a sound scientific explanation for the positive effects of applying horn manure in biodynamic agriculture.

Full study available at Research Gate
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Translation Joshua Kelberman
Photo Sofia Lismont

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  1. M. Zanardo, M. Giannattasio, G. Sablok, M. Pindo, et al., “Metabarcoding analysis of the bacterial and fungal communities during the maturation of preparation 500, used in biodynamic agriculture, suggests a rational link between horn and manure,” Environment, Development, and Sustainability. (March 22, 2023): 1–19.

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