Postemergent

Referring to the phase in a plant's growth subsequent to the emergence of its initial leaves from the soil, the term is specifically employed to characterize a category of herbicides designed for application on weeds that have already developed leaves. Post-emergent herbicides, like glyphosate, typically function by destroying the cells of fully developed leaves, hindering photosynthesis and leading to the demise of the entire plant. They tend to have limited effectiveness on very young plants and seeds.