Fig. 3. Measured maximum (open symbol) and minimum (shaded symbol) UV-B transmittances by plot with fitted line (dashed line), as a function of LAI for (a) alfalfa under clear sky conditions; (b) alfalfa under overcast sky conditions; and (c) tall fescue under clear sky conditions. Fitted lines were determined using a weighted estimate of k (inverse of standard error), thus, unequal weighting of data points (i.e., best fit line is influenced by some points more than others).