Why does grass stain your clothes?

Grass stains occur due to the presence of chlorophyll, which is the green pigment in plants, and other organic compounds found in grass. When you come into contact with grass, these substances can transfer to your clothing and become embedded in the fabric. The combination of moisture and friction can make it difficult to remove the stain, as the chlorophyll binds to the fibers. Additionally, the longer the stain sits, the more challenging it becomes to eliminate.