According to FAO (2006), Brazil is the highest emitter of methane from cattle, followed by India and the USA (9.6, 8.6 and 5.1 Mt CH4/yr, respectively). In livestock, CH4, formed from enteric fermentation of carbohydrates, is primarily responsible for the emissions by the agricultural sector. Regarding livestock methane emission, Delgado et al. (2012) evaluated 20 tree and shrub species using in vitro techniques and demonstrated lower methane production from Tithonia diversifolia, a member of the Asteraceae family, than from grasses, for example, Cynodon nlemfuensis. T. diversifolia can be very useful, not only in animal nutrition, e.g. in silvopastoral arrangements (Plate 1), by increasing the protein content of animal diets at low cost (Murgueitio et al. 2010), but also in the recovery of degraded soils, for it grows in areas with low levels of fertility. Furthermore, it has a high phosphorus uptake ability, even if P is unavailable to other forage species (Kwabiah et al. 2003). The objective of this study was to assess the nutritional quality, including quantification of enteric methane generated during in vitro ruminal fermentation, of T. diversifolia as a forage for ruminant nutrition in the tropics.