Harvest impacts in uneven-aged and even-aged Missouri Ozark forests

Forest managers are concerned about the potential damage to residual trees and site from cyclic harvest re-entries into the same forest stand. This study summarizes logging and felling damage resulting from the harvesting of silvicultural treatments on a large landscape experiment in southern Missouri that is designed to compare impacts of even-aged, uneven-aged and no management on a wide array of ecosystem components. Although damage levels to bole and crown of leave trees was low for all treatments, the individual tree selection (uneven-aged) treatment did show: (1) higher levels of surface area skidder impact; (2) higher percentage of leave trees with one or more bole wounds; (3) higher number of bole wounds; (4) higher percentage of wounded trees in the dominant and co-dominant crown classes; and (5) the highest percentage of leave trees impacted by logging activity. Preharvest planning that involves the layout and discussion with the skidder operator(s) will reduce the area impacted by skidding to less than 12%. Also, the probability of a bole wound to a residual tree can be reduced to less than 5% if skid trails are kept 30 ft or more from the leave tree.