Grammia arge (arge moth) is a moth of the family Erebidae. It is found from Quebec and Maine to Florida, west to New Mexico, north to North Dakota and Ontario. The wingspan is 38–50 millimetres (1.5–2.0 in). Adults are on wing from April to September in most of the range and from July to September in Quebec. There are two generations per year in the south and one or two in the north. The larvae feed on the leaves of corn, dock, lambs-quarter, Chenopodium, grape, plantain, Opuntia, smartweed and sunflower.