Once in a while you find something useful on Facebook. This is a common recipe for weed killer that works quite well and doesn’t leave a dangerous residue for children and pets.
One gallon vinegar
2 cups Epsom Salt
1/4 cup dish soap (Dawn for the cuticle dissolving properties)
Mix these ingredients together in proportion in a metal or plastic container for spraying. Brown or white vinegar may be used successfully. Table salt may be substituted, but make sure you let it all dissolve to avoid plugging the spray nozzle. Spray generously on leaves of unwanted plants in the morning hours, covering all leaves until dripping. Leaves will brown and dry up within hours in the sunshine. Spray all mixed solution – do not store in the sprayer as the salt will corrode it all.