We classified red spruce (PicearubensSarg.) sites from northern Maine by radial growth release history. Two major releases were apparent for a majority of the sites. The first was a reduction and subsequent increase in radial increment in 1920. The second was an increase in radial increment from 1935 to 1955. Red spruce radial growth reduction in the 1960s is apparent only for sites released from 1935 to 1955 (approximately 54% of the sites in this study). These sites are now approaching the radial growth rates of the unreleased stands. Birch dieback is suggested as a probable contributor to the 1935–1955 red spruce growth increase and subsequent 1960s growth reduction.