What do contact herbicides do?

Contact herbicides are designed to kill only the parts of the plant that they directly touch. When applied, these herbicides work by damaging the cells in the area of contact, leading to the death of that specific plant tissue. This characteristic makes contact herbicides particularly effective for controlling annual weeds and certain soft-bodied perennials.

In contrast, translocating herbicides move throughout the plant, affecting tissues that are not directly contacted during application. They are typically designed to impact the entire plant, including the roots and stems, leading to a more holistic control of the weed. The option of promoting rapid growth does not apply to contact herbicides; rather, their function is to inhibit or kill plant growth. Additionally, soaking into the soil is a characteristic more relevant to systemic herbicides, which can also be absorbed by roots, impacting the plant from within. Thus, the primary action of contact herbicides is localized to the area they touch, making the understanding of this mechanism crucial for effective weed management.