Cyanazine solution is primarily used as a selective herbicide in agricultural settings. It effectively controls annual grasses and broadleaf weeds in crops such as corn, sugarcane, and certain vegetables. The chemical works by inhibiting photosynthesis in susceptible plants, leading to their gradual decline and death. Due to its systemic action, it is often applied pre-emergence or early post-emergence to maximize weed control while minimizing crop damage. Its use has declined in recent years due to environmental concerns, particularly regarding groundwater contamination and toxicity to aquatic life. Where still permitted, it is applied with careful attention to dosage, timing, and environmental conditions to reduce off-target effects.