Fig. 2. Mean midday C exchange rate of well-watered (W) and water-stressed (D) guayule the day before and the day after irrigation in June, July, and August 2003. Carbon exchange measurements were recorded within 1 h of solar noon. Measurements were taken on 19 plants in each irrigation treatment (five plants in each of four replications, with one plant missing in one replication). The vertical bar indicates ± standard error.