Defoliation alone was detrimental to oak regeneration, while thinning moderated the defoliation effect. Oak regeneration was greatest on control stands and stands that were thinned but not defoliated. For both defoliated and undefoliated stands, any effect of thinning on total seedling abundance was lost by 1992. Total seedling production increased significantly on thinned stands two years following thinning, but differences disappeared by third year after treatment. The general response to defoliation was similar in number of seedlings irrespective of thinning, i.e., there was an initial depression of regeneration, although it was more noticeable in stands that were not thinned. Data were collected from these stands for three years subsequent to the disturbances. Five stands were neither thinned nor defoliated. Three stands were thinned and defoliated while five were thinned only and three were defoliated only. Overstory species regeneration was examined in 1989, prior to gypsy moth defoliation and thinnings, on 16 stands in the West Virginia University Forest. Department of Agriculture, Forest Service, Northeastern Forest Experiment Station. Proceedings, 10th Central Hardwood Forest Conference 1995 March 5-8 Morgantown, WV.: Gen.
Publication Series: General Technical Report (GTR).
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