Which statement about translocated herbicides is correct?

• A. They act on surface leaves only
• B. They evaporate quickly
• C. They kill only annuals
• D. They move within the plant to reach vegetative reproductive structures

Answer: (D)

Translocated herbicides are systemic drugs of weed control. After the chemical is absorbed, it moves through the plant’s vascular system to reach growth points, including vegetative and reproductive structures. This mobility is what makes them effective against perennials and woody weeds as well as annuals, because the active ingredient can travel to roots, rhizomes, and meristems where new growth would occur. That’s why the statement that they move within the plant to reach vegetative reproductive structures is correct. They are not limited to surface leaves—that describes contact herbicides, which act only where they touch. They don’t rely on evaporation as their main behavior, and they aren’t limited to killing only annuals, since their systemic movement allows control of perennial forms too.