What does a contact herbicide do?

A contact herbicide is specifically designed to kill only the parts of the plant that it directly contacts. This type of herbicide works on the principle that when it comes into contact with the plant's tissue — typically leaves or stems — it disrupts cellular functions in those areas, leading to cell death and consequently killing the targeted plant parts.

This mechanism is in contrast to systemic herbicides, which are absorbed and then transported throughout the plant, affecting its entire structure. Contact herbicides do not have the ability to move within the plant to reach untreated areas, and they are often used in situations where precision is necessary, such as in spot treatments or in areas where desirable plants are located nearby that the applicator wishes to protect.