Understanding root growth response of creeping bentgrass (Agrostis stolonifera L.) to coring will help golf course superintendents maintain high quality putting green turf. Th e objective of this fi eld study was to examine the eff ects of coring on summer rooting in young creeping bentgrass grown on a sand-based root zone and maintained as a putting green. Th e study was initiated on 7-mo-old ‘Providence’ creeping bentgrass in 2006 and compared spring (SP) only coring, spring plus three summer (SU) corings (SP + SU) and a noncored control through 2007. Th e minirhizotron imagining technique was used to measure total root count (TRC) and total root length (TRL) from late spring to  late summer. Th e percentage of the TRC in the surface 0- to 6-cm root zone depth averaged over measurement dates was 48 to 53% and 33 to 44% among all treatments in 2006 and 2007, respectively. Greater TRC were observed in 2006 with 28, 51, and 50% lower TRC’s found in SP + SU, SP only, and noncored plots in 2007, respectively. Spring + SU coring generally reduced TRC and TRL at various root zone depths and dates during the first year of est -ablishment. In 2007, greater TRC and TRL were observed throughout the 0- to 24-cm root zone in SP + SU cored compared to SP only and noncored plots. Th us, SP + SU coring in the second study year promoted creeping bentgrass root growth and/or longevity, but coring during the fi rst summer of establishment reduced rooting.