Salix nigra bark of the tree contains salicylic acid, a chemical compound similar to aspirin (acetylsalicylic acid). It may also be used as an environmental restorative. Swamp trees in general are, by necessity, good at surviving and thriving in areas where highly mobile environmental toxins are present. Black Willow is very resistant to herbivory and flooding and is also a fantastic erosion control tool. Thus, it is useful for any sort of marshland stabilization or restorative as long as the roots don’t penetrate any clay liner that may be in place. In a relatively extensive phytoremediation study, "Salix nigra" demonstrated some success
Gallic acid contain various amounts of gallic acid, especially fruits (including strawberries, grapes, bananas), as well as teas, cloves, and vinegars. Gallic acid is easily freed from gallotannins by acidic or alkaline hydrolysis. When gallic acid is heated with concentrated sulfuric acid, rufigallol is produced by condensation. Oxidation with arsenic acid, permanganate, persulfate, or iodine yields ellagic acid, as does reaction of methyl gallate with iron(III) chloride. Reference Also known as galloylated esters: Gallic acid Gallic acid (also known as 3,4,5-trihydroxybenzoic acid) is a trihydroxybenzoic acid, a type of phenolic acid, found in gallnuts, sumac, witch hazel, tea leaves, oak bark, and