Hibiscus trionum is an annual herb to 50 cm tall, very hairy, branching.
Leaves alternate, deeply 3-parted, middle lobe longest, segments oblong, coarsely toothed or lobed.
Flowers pale yellow with purple center, broad, lasting only a few hours, petals 5, to 4 cm long, widest at top, calyx becoming infflated, 5-angled or winged, coarsely hairy.
Fruit enclosed in hairy sepals; blooms and fruits July-Sept.
Wetland status: UPL.
Frequency in NYC: Very infrequent.
Habitat: Open areas, roadsides.