What is the function of systemic herbicides?

Systemic herbicides are designed to be absorbed by the plant and translocated throughout its vascular system. This means that when systemic herbicides are applied, they move through the entire plant, reaching all parts, including leaves, stems, and roots. By moving within the plant, these herbicides effectively target and disrupt vital physiological processes, leading to the death of the weed.

The ability to translocate allows systemic herbicides to be particularly effective against perennial weeds, which may have extensive root systems. They can ensure the herbicide is applied efficiently to the most resistant parts of the plant, such as the roots. This whole-plant action sets systemic herbicides apart from contact herbicides, which only affect the parts of the plant that they directly hit.

Other options involve functions that are not characteristic of systemic herbicides. For instance, acting only on the surface of the leaves describes contact herbicides, while controlling soil erosion and improving photosynthesis hint towards different categories of products and processes not related to herbicide functionality.