The dataset consists of ACi (net CO2 assimilation rate, A, versus calculated substomatal CO2 concentration, Ci) curve data from an ozone experiment during which Trifolium repens and Lolium perenne were exposed as both monocultures and two-species mixtures to an episodic rural ozone regime in large, well-watered containers within solardomes for 12 weeks. Treatments were elevated ozone (AOT40 (Accumulated Ozone Threshold exposure of 40 parts per billion) of 12.86 ppm h) or control conditions (AOT40 of...