John Bailey gained his PhD at Leicester University on Japanese Knotweed and its hybrids, co-supervised by Ann Conolly and Clive Stace, which established the cytological basis of the genus. He has since travelled extensively on knotweed research activities and speaking at conferences. With the aid of three PhD students, he took advantage of new DNA technologies to further elucidate population structure, evolution and phylogeny of the genus Reynoutria. He has contributed to more than 40 scientific papers on the subject and has a current h-index of 36.