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 LiveStd. Err.SdeadStd. Err.FWDStd. Err.CWDStd. Err.

Red pine4−0.870.51−0.030.06−0.130.10−0.140.13
Balsam fir4−0.170.71−0.360.42−0.180.11−0.340.18
Black spruce40.440.430.100.06−0.090.05−0.800.75
Northern white cedar7−0.300.23−
White/red oak and hickory31−0.030.320.050.13−
White oak10−0.910.
Elm/Ash/Black Locust12−0.420.16−0.460.16−0.680.74−0.750.43
Mixed upland hardwoods100.460.76−0.530.68−0.120.19−0.200.24
Black ash/American elm/red maple8−0.530.32−
Silver maple/American elm4−1.850.60−0.120.08−0.200.17−0.280.98
Sugar maple/beech/yellow birch120.070.40−
Hard maple/basswood9−0.310.38−0.330.27−.
Balsam poplar4−0.470.20−