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Black Spruce

Mortality for Mid-Rotation and Old-Growth Black Spruce

For Black Spruce with DBH>4, annual survival probability (Ps) is predicted using a logistic model.

Pslogistic = exp(c) / (1+exp(c))

Where: C = 4.1334504 + 0.0357828 * dbh - 0.00351298 * Dbh2 + 2.859369 * stAvDbh / dbh - 0.0268818 * stBa - 0.657523 * stSc - 0.036622 * SI

DBH is in cm

stAvgDBH is the stand average DBH

stBa is the stand basal area (m2/ha)

stSc = Black Spruce relative composition of the stand by BA

SI is the black spruce site index


Note: if the MaxDenAdj flag is on, black spruce survival will be adjusted is stand density exceeds the self-thinning line.