Culms 70-200 cm tall, 6-8 mm thick at the base. Ligules 3-7(9) mm; blades 20-45 cm long, 4-12 mm wide. Panicles 15-30 cm; primary branchesascending to divergent, spikelets appressed to the branches. Spikelets 7-11 mm. Lower glumes 5-8 mm; upper glumes 6.5-9 mm; calluses about 0.5 mm; lemmas 4-9 mm; paleas about as long as the lemmas; anthers 2-4 mm. 2n = 28.
Scolochloa festucacea grows in ponds, marshes, seasonally flooded basins, and shallow margins of freshwater to moderately saline lakes and streams. It provides good nesting cover for some waterfowl and shorebirds, and can provide valuable forage for livestock and wildlife. It does not compete well with hybrid cattails (Typha latifolia × T. angustifolia or T. domingensis).