Over three production years (2021–2024), this study investigated the effects of incorporating plantain into a perennial ryegrass–white clover (RGWC) mixed sward on dairy farm productivity and environmental footprint. Seventy‐two Friesian × Jersey cows were allocated to six farmlets across two replicated herbage treatments (n = 3): RGWC with no plantain (PL0) or RGWC plus 3 kg/ha of plantain seed (PL3). Farmlet production data were used to estimate profitability using the FARMAX model and the environmental footprint using the OverseerEd model. Plantain content in PL3 averaged 23. 5% (±2. 31%; SD) in Year 1, 16. 8% (±2. 46%) in Year 2 and 12. 3% (±1. 12%) in Year 3. Annual herbage production was similar across treatments when estimated by FARMAX (15. 7 kg DM/ha) but showed a year × treatment interaction (p < 0. 001) when estimated by calibrated rising plate meter. Annual imported silage (1. 24 t DM/ha) and milksolids production (1458 kg/ha) were similar across treatments. Farm profitability did not differ between treatments (NZD 5800/ha), indicating no economic disadvantage from plantain inclusion. Modelled annual nitrogen leaching was 17. 5% lower in PL3 than PL0 (p = 0. 032), with no difference in methane emissions. These results suggest that incorporating plantain into RGWC‐based dairy systems can improve environmental sustainability without compromising milk production or profitability.
Hintz et al. (Sun,) studied this question.