What does the term 'post-emergent' imply about the timing of herbicide application?

• A. Applied before weeds emerge.
• B. Applied after weeds have emerged; example: 2,4-D.
• C. Applied at harvest.
• D. Applied only to soil.

Answer: (B)

Post-emergent means the herbicide is applied after the weeds have emerged from the soil and are visible above ground. It targets actively growing plants that have already germinated, often through foliar uptake, and is most effective when weeds are small and actively growing. This contrasts with pre-emergent use, which is applied before emergence to prevent germination, and with applications intended for soil-only effects or timing at harvest. An example like 2,4-D is typically used as a post-emergent herbicide to control broadleaf weeds after they have emerged.