blogs.vancouversun.com — Among the common practices of biodynamic agriculture is the making of Preparation 500, in which manure from a lactating cow is buried underground for the winter in a hollowed out cow's horn. Summerhill Pyramid Winery CEO Ezra Cipes admits there are elements of biodynamic farming that sound more like witchcraft than modern agriculture, but he insists you can taste the results in a superior glass of wine.