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Modification to the law of the wall represented by a dimensionless correction function ϕ RSL (z/h) is derived using atmospheric turbulence measurements collected at two sites in the Amazon in near-neutral stratification, where z is the distance from the forest floor and h is the mean canopy height. The sites are the Amazon Tall Tower Observatory for z/h∈[1, 2.3] and the Green Ocean Amazon (GoAmazon) site for z/h∈[1, 1.4]⁠. A link between the vertical velocity spectrum E w w (k)(k is the longitudinal wavenumber) and ϕ RSL is then established using a co-spectral budget (CSB) model interpreted by the moving-equilibrium hypothesis. The key finding is that ϕ RSL is determined by the ratio of two turbulent viscosities and is given as ν t, B L/ν t, RSL⁠, where ν t, RSL=(1/A)∫ 0∞ τ (k) E w w (k) d k⁠, ν t, B L= k v (z− d) u*⁠, τ (k) is a scale-dependent decorrelation time scale between velocity components, A= C R/(1− C I …