At room temperature (about 25°C), corn stover briquettes (about 19.2 mm diameter) with relaxed densities (i.e., individual briquette densities measured one week after forming) of 745 to 1013 kg m-3 and switchgrass briquettes (about 19.4 mm diameter) with relaxed densities of 417 to 825 kg m-3 were produced.