The effect of different gravel thickness treatments (circle: 0 cm, triangle: 2.5 cm, square: 7.5 cm) on average maximum (open symbols), minimum (filled symbols), and mean average (gray symbols) daily temperature in different depths in solarized and non-solarized plots in trial 2 in CA. Non-linear regression lines are shown for each gravel treatment (solid lines: 0 cm gravel, dashed lines: 2.5 cm gravel, dotted lines: 7.5 cm gravel thickness). Similar trends were observed in other trials.