Figure 8 . Simulated effects of leaf hairs (contributing a resistance of r h = 0.1 m2 s mol-1 on (a) net CO2 assimilation rate (A ), (b) transpiration rate (E ), (c) water use efficiency (WUE = A/E ), and (d) leaf temperature (T leaf), under various conditions for the X variables listed in the legend. The ranges and default values for each X variable were as follows: leaf size (0.01 to 0.30 m, default 0.1), stomatal conductance (0.001 to 1.0 mol m-2s-1, default 0.18), PPFD (0 to 2000 µmol m-2 s-1, default 1000), air temperature (5 to 45oC, default 25), and ambient humidity (0.002 to 0.03 mol mol-1, default 0.01). Results for X = leaf size are shown for two air temperatures (25oC and 10oC). The dashed grey line indicates zero change. Note that % changes are shown for A ,E and WUE, whereas absolute changes are shown forT leaf.