Technical Abstract: The objective of this research was to identify and quantify the phenolic acids present in the seeds 3 of three wild-type populations of wild oat and compare these results to the phenolic acid 4 composition and concentration of seeds from two commonly utilized wild oat isolines (M73 and 5 SH430). Phenolic acids have been shown to serve as germination inhibitors, as well as protection 6 for seeds from biotic and abiotic stress factors in other species. The various populations of wild 7 oat were grown under a ‘common garden’ environment to remove maternal variation and the 8 resulting seeds were extracted to remove the readily soluble and chemically bound phenolic acid 9 components. Phenolic acids were identified and quantified using gas chromatography – mass 10 spectrometry. Ferulic and p-coumaric acid comprised 99% of the total phenolic acids present in 11 the seeds, of which 91% were contained in the hulls and 98% were in the chemically bound 12 forms. Smaller quantities of OH-benzoic and vanillic acid were also detected.