Effects of different silvicultural systems on initial soft mast production
Recent policy changes by federal land management agencies such as the United States [Department of Agriculture] Forest Service have led to increased use of silvicultural systems other than clearcutting. Because soft mast is an integral part of wildlife habitat and the effects of these alternative silviculture systems on soft mast production are unknown, we evaluated effects of different stand-level silvicultural systems on soft mast production in the Ouachita Mountains of Arkansas and Oklahoma. We evaluated differences in soft mast production and coverage among 4 replications of 5 treatments (clearcut, shelterwood, group selection, single-tree selection, and late-rotation, unharvested forest stands) during the first (1994), third (1996), and fifth (1998) years after initial timber harvest. Coverage of all mast-producing plants combined did not differ among treatments over all years. Soft mast production did not differ among treatments the first year after timber harvest, but was greater in harvested stands than in unharvested stands in the third post-harvest year. Production in shelterwood cuts and clearcuts was greater than in single-tree selection, group selections, and unharvested stands the fifth post-harvest year. Unharvested stands, greenbelts (unharvested buffers surrounding stream drainages), and the thinned matrix of group-selection stands produced little mast in all years. A significant linear relationship between soft mast production and residual overstory basal area was present in years 3 and 5. We present equations to predict soft mast production 3 and 5 years after harvest when residual overstory basal areas are known. Without additional stand treatments (e.g., thinning or burning), we expect production in even-aged stands (clearcuts and shelterwood cuts) to decline as canopy closure progresses; likewise, production in single-tree selection stands will likely decline due to midstory development.