Systemic herbicides kill weeds on contact.

• A. True
• B. False

Answer: (B)

The statement about systemic herbicides killing weeds on contact is false. Systemic herbicides are designed to be absorbed by the plant and translocated throughout its tissues, which allows them to target the entire plant system, including the roots, stems, and leaves. This internal action is what makes systemic herbicides effective for eliminating deeply rooted and perennial weeds, as they disrupt vital physiological processes.

In contrast, contact herbicides are the ones that kill weeds upon physical contact. These chemicals do not penetrate the plant's system but instead destroy the tissues of the parts of the plant they touch.

Understanding this distinction between systemic and contact herbicides is crucial for effective weed management in agricultural and landscaping practices. It is also essential for applicators to select the appropriate type of herbicide based on the target weeds and their growth stages.