The data are biomass and ozone-injury data for white clover (Trifolium repens). Dataset concerns a 2014 study on the effects of Jasmonic acid/cutting in modulating the response of clover to ozone. A short-term (4-week) ozone-exposure experiment was conducted in 2014 to investigate the interactive effects of cutting on ozone-induced responses in white clover (Trifolium repens). A strong interaction was found in root biomass and root nodule biomass in cut white clover plants in a high ozone background (45-67 parts per billion (ppb) treatment mean), suggesting ozone-impacts on root nodule biomass occur through limitation of carbon availability. The work was carried out as part of a NERC funded PhD.