But its active ingredient, pendimethalin, is a pre- and early post-emergent herbicide for both broadleaf and grassy weeds. It works by preventing cell elongation, thereby stopping shoot and root ...

in order to reduce the pressure on post-emergence chemistry. He recommends a pendimethalin-based product, such as Stomp, at 1,000-1,200g active/ha, followed by a full-rate post-emergence spray ...