Flower:

Elongating cluster of white flowers on slender stalks at the top of the plant and arising from leaf axils in the upper plant. Flowers are about ½ inch across, have 4 white petals with rounded tips each 2.5 to 4.5 mm long, and 6 creamy white to pale yellow stamens in the center. The 4 sepals behind the flower are much shorter than the petals, pale greenish white around the edges. Flower stalks and sepals are all hairless.

Leaves and stems:

There are both basal and alternate stem leaves. Basal and lower stem leaves are ¾ to 2 inches (2 to 4+ cm) long, oval, round to kidney shaped, hairless, on a stalk usually longer than the leaf blade. The edges may be toothed, scalloped, or toothless, and are often wavy.

The 2 to 4 stem leaves are typically widely spaced and become less round, proportionately longer and narrower as they ascend the stem, the uppermost leaves stalkless and more generally oblong, longer than the basal leaves and the edges toothless or with a few irregular teeth. Stems are hairless or sparsely hairy and mostly unbranched except near the flowers.

Fruit:

Fruit is a straight, linear, flattened pod about 1 inch (2 to 3.5 cm) long, the stalks ascending to spreading and the pods mostly ascending.

Notes:

Spring Cress, formerly Cardamine rhomboidea, is fairly easy to identify from its roundish, unlobed basal leaves and narrowing stem leaves. The flowers are most similar to Cut-leaf Toothwort (Cardamine concatenata), which has deeply lobed leaves, is a shorter plant, and primarily a woodland species. While Spring Cress is not an uncommon species, unless you like traipsing around mucky seeps and wetlands, it is not so likely to be encountered.