Cell wall polysaccharides contain a small amount of ester-linked hydroxycinnamic acid derivatives, such as p-coumaric and ferulic acids. These hydroxycinnamic acids can be coupled oxidatively to form the acid dimers. Dimer formation in the growing plant cell wall would cause the cross-linkage of cell wall polysaccharides and lead to an increase in wall rigidity. Feruloyl polysaccharide esters would also participate with lignin monomers in oxidative coupling pathways to generate a ferulate-polysaccharide-lignin complexes during cell wall development. Feruloyl oligosaccharides derived from feruloyl polysaccharides have been shown to inhibit cell elongation growth induced by auxin or gibberellins. Feruloyl polysaccharides are critical entities in directing wall cross-linking and in limiting biodegradability by microorganisms.