Context Tropical forages can improve livestock productivity while reducing methane emissions in smallholder crop–livestock systems. Aims This study evaluated forage mass, forage quality, methane mitigation potential of 12 tropical species at two contrasting sites in the Ethiopian highlands: Hawassa in the south and Bahir Dar in the north. Methods Field experiments were conducted from 2021 to 2023, with two to four cuts per year by using a randomized complete block design. Plant samples were also evaluated for chemical composition and in vitro methane production. Key results Results showed significant site-specific variations, with desho grass (Pennisetum pedicellatum) demonstrating consistently high forage mass production (27.3 Mg ha−1 at Hawassa; 17.58 Mg ha−1 at Bahir Dar) across these environments. Legumes, particularly sunnhemp (Crotalaria juncea L.) and lablab (Lablab purpureus L.), exhibited the highest crude protein yield (590–1300 kg ha−1 year−1) but lower forage production, highlighting their role as supplemental feed sources. Methane mitigation potential also exhibited variations, with lablab, Mombasa (Megathyrsus maximus) and desho producing the lowest emissions (27%) warrant further evaluation. Conclusions The study identified desho and Mombasa as promising options for site-specific forage development because of their dual benefits of productivity and in vitro methane mitigation. Legumes such as sunnhemp and lablab are recommended as high-quality supplements to existing feeding strategies. Implications These findings have provided actionable insights for extension officers, policy makers and researchers seeking to balance livestock productivity with environmental sustainability in Ethiopian highlands. Future research should focus on validating methane mitigation potential under in vivo conditions and addressing challenges in legume establishment.
Raji et al. (Wed,) studied this question.