In this study, we report fuel properties (basic density, high heating value, proximate and elemental parameters) and ash elemental composition of two important forest weed species, i.e. Lantana camara and Eupatorium spp. The physical, chemical and elemental properties of L. camara and Eupatorium spp. were compared with those of a mature tree (20 years of age) of Eucalyptus hybrid. The combustion characteristics under oxidizing atmosphere were also studied using thermogravimetric analysis. The burning profiles of the samples were derived by applying the derivative thermogravimetric technique. The two weed species were found to be different in their physical, chemical and elemental properties. The fuel properties and
combustion characteristics, which largely depend upon the biochemical composition of biomass, were also different in these two weed species. The results suggested that both L. camara and Eupatorium spp. can be used as feedstock in thermochemical conversion processes. The emphasis was given to these species because of the huge biomass they produce. These species are widely present in different agroclimatic zones of India and can play a major role in future bioenergy schemes.