Flag leaf blades 5-39 cm long. Panicles (9.5-)13-40 cm long. Glumes 8-15 mm long; anthers 3.5-7 mm long.
Ammophila breviligulata subsp. breviligulata grows on sand dunes and dry, sandy shores from around the Great Lakes to the Atlantic Coast from Newfoundland to South Carolina and, as an introduction on the west coast. It flowers from late July to September whereas Ammophila breviligulata subsp. champlainensis flowers from June to early July.