Table 2: Average annual carbon flux by forest type for down woody material components where n 3: live (standing live trees), Sdead (standing dead trees), FWD (fine woody debris), and CWD (coarse woody debris) where a negative estimate indicates a net sequestration north central across the United States, 2002 to 2007.

Forest type Live Std. Err. Sdead Std. Err. FWD Std. Err. CWD Std. Err. Red pine 4 −0.87 0.51 −0.03 0.06 −0.13 0.10 −0.14 0.13 Balsam fir 4 −0.17 0.71 −0.36 0.42 −0.18 0.11 −0.34 0.18 Black spruce 4 0.44 0.43 0.10 0.06 −0.09 0.05 −0.80 0.75 Northern white cedar 7 −0.30 0.23 −0.05 0.05 0.13 0.08 0.27 0.15 White/red oak and hickory 31 −0.03 0.32 0.05 0.13 −0.13 0.10 0.23 0.19 White oak 10 −0.91 0.09 0.00 0.02 0.19 0.08 0.17 0.24 Elm/Ash/Black Locust 12 −0.42 0.16 −0.46 0.16 −0.68 0.74 −0.75 0.43 Mixed upland hardwoods 10 0.46 0.76 −0.53 0.68 −0.12 0.19 −0.20 0.24 Black ash/American elm/red maple 8 −0.53 0.32 −0.08 0.21 0.03 0.25 0.30 0.22 Silver maple/American elm 4 −1.85 0.60 −0.12 0.08 −0.20 0.17 −0.28 0.98 Sugar maple/beech/yellow birch 12 0.07 0.40 −0.20 0.14 0.14 0.10 0.34 0.20 Hard maple/basswood 9 −0.31 0.38 −0.33 0.27 −.20 0.12 0.14 0.39 Aspen 14 −0.36 0.20 −0.02 0.08 0.04 0.13 0.11 0.28 Balsam poplar 4 −0.47 0.20 −0.23 0.20 0.08 0.28 0.04 0.09