Planting has been considered to be one solution to the problem of inadequate natural oak regeneration following harvesting in the Central Hardwood Region. Two types of tree shelters were used in two separate 3-year studies to determine their effects on the growth and survival of northern red oak seedlings planted in recently harvested forest openings, and to characterize shelter influence on microenvironmental factors. Sheltered seedlings planted in both trials exhibited significantly greater 3-year height growth as compared to the controls. There were no significant differences in survival rates. Relative humidity and carbon dioxide concentrations were increased significantly inside both types of shelters, while there were no differences between shelter exterior and interior daytime temperatures. Interior light intensities differed for the two shelter types and varied according to vertical location within shelters. Recommendations are given for using tree shelters as a possible means for improving oak planting success in recently harvested forest openings. North. J. Appl. For. 9(2):58-63.