Terbuthylazine is primarily used as a selective herbicide in agriculture, especially in the cultivation of corn and other row crops. It controls a broad spectrum of annual grasses and broadleaf weeds by inhibiting photosynthesis in susceptible plants. Due to its soil residual activity, it provides extended weed control, reducing the need for frequent reapplication. It is often applied pre-emergence or early post-emergence to weeds, making it effective in integrated weed management programs. Terbuthylazine is valued for its performance in low-dose applications and compatibility with various crop protection products, enhancing its utility in modern farming systems.