Cyanazine is primarily used as a herbicide in agricultural practices to control the growth of broadleaf weeds and grasses in crops such as corn, sorghum, and sugarcane. It works by inhibiting photosynthesis in target plants, effectively stopping their growth and preventing them from competing with crops for nutrients, water, and sunlight. This helps to improve crop yield and quality. Cyanazine is typically applied pre-emergence or early post-emergence, depending on the crop and weed species. However, due to environmental and health concerns, its use has been restricted or phased out in several regions, with farmers often transitioning to alternative herbicides with lower environmental impact.