Capsella bursa-pastoris (L.) Medik.
Family: Brassicaceae
Capsella bursa-pastoris image
Merel R. Black  
Etymology: Capsella: Latin for "a little box"
Plants: erect, annual, 4"-24" tall forb, with a few branches
Leaves: basal leaves oblong, pinnately-lobed; stem leaves smaller, mostly linear, appearing to clasp the stem with the 2 basal lobes
Flowers: white, 4-parted, 1/4" wide, petals longer than the sepals; inflorescence a dense cluster (raceme) of stalked flowers, elongating with age; blooms April-Aug.
Fruits: heart-shaped to triangular, flat pod fruit drawing
Habitat: disturbed sites such as lawns and roadsides
Conservation Status: Introduced - naturalized