Castor oil, the active ingredient in Tomcat 0348206 Mole and Gopher Repellent, works by making the soil unpleasant for moles—not toxic, but irritating. When applied using the product’s Ground Penetrating Technology, the castor oil mixes with water and penetrates deep into the soil. This alters the scent and taste of the soil, disrupting the moles’ food sources (like earthworms) and their sensitive tunneling environment. Instead of killing them, it drives moles away by creating a habitat they find intolerable. Think of it as a gentle eviction notice backed by nature’s chemistry