Table 2.

Significance probabilities and F ratio generated by an analysis of variance (ANOVA) of the effects of commercial parking lot planting location (landscape median and perimeter) and time of year (April and August 2002) on leaf gas exchange [net carbon assimilation (A), stomatal conductance (gs), internal leaf to ambient CO2 concentration (Ci/Ca)] and leaf chlorophyll concentration (Chl) of four landscape tree species in Phoenix, Arizona.

Tree species/ANOVAAgsCi/CaChl
Australian bottle tree
Time of year0.00010.00010.00920.0001
Location × time0.00010.00010.16390.0001
F ratio23.4517.4812.097.41
Arizona ash
Time of year0.24330.00010.00010.0001
Location × time0.01910.10120.00010.3351
F ratio18.8852.15177.7811.92
Argentine mesquite
Time of year0.00410.00010.00010.4340
Location × time0.23670.06520.16380.0077
F ratio10.459.9697.882.96
Chinese elm
Time of year0.00010.87760.00010.0001
Location × time0.00610.00040.00020.0008
F ratio9.816.1516.269.39