ABSTRACT This study comparatively analysed biogas production from three waste materials: Grass - Axonopus compressus, cow dung and pig waste slurry, with respect to the effects of carbon/nitrogen (C:N) ratio on biogas yield. A mixing ratio of 1:10 (one (1) part of substrate to ten (10) parts of water) was used. Nine 2L plastic digesters, were used for the study. Digestion was carried out in triplicates, 3 digesters for each substrate. The C:N ratios of the substrates were as follows: Axonop...