Sisyrinchium angustifolium is a perennial, monocotyledon herb, 15-50 cm tall; stems clumped, flat, broadly winged, 0.3-0.4 cm wide, individual wings wider than center of stem, flowering stems branching from leaf-like bracts 2-4 cm long in middle of stem, bracts stalked.
Leaves all basal, flat, linear, 0.2-0.6 cm wide.
Flowers radially symmetrical, pale-medium blue, petals and sepals the same, 0.7-1 cm long, 3 each; blooming June-July.
Fruit becoming dry blackish, round capsules, 0.4-0.6 cm wide, fruiting stems usually prostrate dropping seeds around edges of parent plant.
Wetland status: FACW-.
Frequency in NYC: Infrequent.
Origin: Native. Moist to wet.
Habitat: Open ground. Wet meadows.