Sugar Maple Decline Following Whole-Tree Harvest of Watershed 5

w5cut_MaryArthur_a.pngIn 1985 we conducted a whole-tree harvest experiment on W5 to evaluate how forest ecosystems respond to this intensive forest management practice and associated high nutrient removal. Periodic measurements on permanent plots across W5 have revealed that sugar maple abundance has drastically declined during thirty years of forest development on W5. Sugar maple comprised nearly half of the forest basal area at the time of whole-tree harvest and now has been relegated to be a minor species, making up less than 4% of forest basal area watershed-wide. The decline in maple abundance was most striking after age 10, as initially regeneration appeared adequate. The decline was most intense in the upper slope positions on W5 where soils have been most severely depleted of calcium by the combination of acid rain and repeated forest harvest. We suggest that low soil calcium availability limits the ability of sugar maple to compete effectively with other tree species like birches and beech. We conclude that forest managers will need to take special care to protect advanced regeneration of heavily cut forests on acidified soils in the eastern United States if they hope to maintain the place of sugar maple in managed forest landscapes.

Natalie L. Cleavitt,  John J. Battles, Chris E. Johnson, Timothy Fahey. 2017. Long-term decline of sugar maple following forest harvest, Hubbard Brook Experimental Forest, New Hampshire. Canadian Journal of Forest Research, https://doi.org/10.1139/cjfr-2017-0233

sugarmaplea_0.png

Changes in the density (stems per square meter, log scale) of sugar maple (ACSA), beech (FAGR) and birches (BETU) in three elevation bands on watershed 5 following whole-tree harvest in 1985. Curves are based on a statistical model of field observations.