Fig. 2 Redness susceptibility (R = hue25 - hue550, where hue25 is hue of field-burned soil and hue550 is the hue after 8 h of exposure to 550°C) of surface (0–5 cm) and subsurface soil (5–15 cm) exposed to different peak surface temperatures during a broadcast field burn. Alphanumeric Munsell hues were converted to numerical values by using a Munsell hue circle (Chamberlin and Chamberlin, 1980) before calculating redness susceptibility. With this conversion 10R = 10, 10YR = 20, and 10Y = 30. Different letters (surface soil only) indicate significant differences at P < 0.05
