High biomass yields have been documented for Tripidium spp. (Erianthus spp., Saccharum spp.), but targeted breeding for bioenergy applications has been limited. Advanced, interspecific hybrids between Tripidium ravennae and T. arundinaceum were planted in replicated field plots in 2016. Comparative feedstock evaluations examined biomass yields, cytogenetics, plant fertility, and compositional analyses relative to Miscanthus × giganteus. Dry biomass yields varied as a function of year and accession and increased each year ranging from 3.4 to 10.6, 8.6 to 37.3, and 23.7 to 60.6 Mg/ha for Tripidium hybrids compared to 2.3, 16.2 and 27.9 Mg/ha for M. × giganteus in 2016, 2017, and 2018, respectively. Cytology and cytometry confirmed that Tripidium hybrids were tetraploid with 2n = 4x = 40 (2C genome size = 5.06 pg) and intermediate between T. ravennae with 2n = 2x = 20 (2C genome size = 2.55 pg) and T. arundinaceum with 2n = 6x = 60 (2C genome size = 7.61 pg). Plant fertility characteristics varied considerably with some accessions producing no viable seeds or fewer than that observed for M. × giganteus. Accessions varied significantly for flowering culm number and height and dates of peak anthesis ranging from 14 September to 2 October. Variations in yield and compositional analyses contributed to variations in theoretical ethanol yields ranging from 10,181 to 27,546 L/ ha for Tripidium accessions compared to 13,095 L/ha for M. × giganteus. Relative feed value (RFV) indices for winter-harvested Tripidium accessions varied from 52.8 to 60.0 compared to M. × giganteus with 45.4. RFV for summer-harvested Tripidium accessions varied from 71.6 to 80.5 compared to M. × giganteus with 61.0. These initial findings for Tripidium hybrids, including high biomass yields, cold hardiness, and desirable traits for multiple markets (e.g., forage, bioenergy, bioproducts), are promising and warrant further development of Tripidium as a temperate bioenergy feedstock. K E Y W O R D S bioenergy, bioprocessing, Erianthus, fertility, forage, lignocellulose, Miscanthus, plant breeding, polyploidy, reproductive biology, Saccharum, sterility, Tripidium [Correction added on 13 April 2020 after first online publication: the genome values have been updated in the Abstract and Results sections in this version.] 362 | MAREN Et Al.Note: Superscript letters indicate statistically significant value p ≤ .05. 1 2C DNA values represent the mean value of three to six samples conducted for each taxon.2 Taxa followed by an asterisk were confirmed with cytology. 3 Values represent the mean ± SEM. Mean separation within columns by Fisher's least significant difference at p ≤ .05. 4 Calculated as (seed set × seed germination)/100. 5 Flowering was not observed within the growing season at the Fletcher, NC evaluation site.