Abstract

The objective of this study was to develop a rapid screening technique to characterize selected red maple (Acer rubrum L.) cultivars based on their gas exchange capacities. Evaluations were conducted in Alabama under ambient conditions on an established, irrigated field trial. In preliminary evaluations 9 red maple cultivars (‘Autumn Flame’, ‘Fairview Flam’, ‘Franksred’, ‘Karpick’, ‘Northwood’, ‘October Glory’, ‘Redskin’, ‘Schlesingeri’, and ‘Tilford’) and 3 Freeman maple (Acer x freemanii E. Murray) selections (‘Autumn Blaze’, ‘Morgan’, and ‘Scarsen’) were observed for differences in net photosynthesis (Pn), transpiration (E), and stomatal conductance (Cs). Based on these results, 4 cultivars of A. rubrum were selected and evaluated intensively over 2 years. Throughout the study, growth rates for the 4 selections failed to correspond with gas exchange observations.