Energetic substances used in homemade weed killers act as contact herbicides, only harming what they touch. Since they only harm prime growth (leaves, stems) and not the root system, they get the job done properly on youthful once-a-year weeds with little roots but are significantly less helpful on perennial weeds https://quincloracsurfactant96517.mybuzzblog.com/11781051/organosilicone-surfactant-for-dummies