Gypsum May make clay soil absorbent when guaranteeing it drains quickly ample to prevent water buildup and root rot. The calcium it provides will also continue to keep grassroots healthful. Map of gypsum deposits in northern Ohio, black squares indicate the location of deposits, from "Geography of Ohio", 1923 Gypsum https://www.propanraya.com/id/produk/eco-gypsum-ee-4050