The above model was derived to describe inside or outside bark cross-sectional area of tree stems. It is a rational function. In the simplest case, defining the model involves estimating 2 regression coefficients using linear regression. The formula is analytically integrable. It provides analytical inside bark volume estimates for any stem section defined by height or diameter limits. The model is analytically solvable for a stem height location at any given inside bark diameter.The model can be calibrated using either section diameter or section volume data. It is suggested that through involving the ratio H/DBH, the model accounts for the influence of stand density on stem profile.