Fig. 2. Estimated juglone pore water concentrations (C_pw) in equilibrium with total extractable juglone (C_s*) from Ryker A horizon soils beneath a black walnut agroforestry system at two locations within the cropping alley (1.2 and 4.2 m from the tree row). The solid line is the prediction from Eq. [1] in which the reversible sorption coefficient was estimated using for average % organic carbon values of the two alley positions. Symbols are predicted C_pw values for specifically measured soil concentrations from the field for reference.