Metsulfuron is a herbicide which belongs to the category of sulfonopyrimidines. It works by inhibiting the production of auxins in plants, which leads to the curling and wilting of the foliage. Metsulfuron is widely used to control grasses and other weeds in cereal crops, gardens, lawns, and golf courses. It is important to follow the proper application protocols and guidelines when using metsulfuron to minimize potential risks to human health and the environment.