Pledge®, from Sumitomo Chemical, is a herbicide with powerful residual effects if applied to the soil and a fast and “burning” effect if applied to foliage. The active ingredient in Pledge®, is flumioxazin, which blocks protoporphyrinogen oxidase (PPO) in chloroplast. With effect from solar power the herbicide causes active oxygen to oxidise lipids in the cell membrane, thus destroying it. The final result is the destruction of chloroplast in the plant, which prevents photosynthesis and brings about its death.
Pledge®, is effective on species missed by glyphosate and has a very good non-selective effect in several plantation crops. Rain matters little to the effect of this product, even shortly after application to foliage. Soil application creates a zone that prevents germination of weeds and a higher dosage results in a long-term effect. Always read and follow label directions.