Fig. 1. Changes in gas-exchange WUE in 2002. Irrigation treatments were applied from 1 July through 18 August for the summer treatment period, and then again from 13 September through 1 November for the fall treatment period. (A) General changes in WUE in response to varying levels of deficit irrigation averaged across all three bentgrass species. Symbols indicate the irrigation treatment as a percentage of ET measurements using weighing minilysimeters. (B) General species changes in WUE averaged across the different levels of deficit irrigation. Vertical bars are LSD values (P 0.05) indicating statistically significant differences for irrigation and species treatment comparisons at a given day of treatment.