Arabidopsis thaliana is an annual or winter annual herb, to 40 cm tall, stem slender, sparsely branched or simple, hairy at base.
Leaves alternate on flowering stem, winter rosette leaves narrow, oblong, hairy, tip rounded, base narrowed to stalk; stem leaves few, narrow, pointed at both ends, stalkless, hairy.
Flowers white, 4-parted, petals to 0.4 cm long spatula-shaped, blooming from branch tips, stems elongate as fruit develops below.
Fruit dry, hollow, narrow to 1.5 x 0.1 cm long on stalk 1.5 cm long, splitting open to release 40-68, tiny seeds; March-June.
Wetland status: UPL.
Frequency in NYC: Very infrequent.
Habitat: Open, soil, roadsides, prefers sandy soil. An agricultural weed.