Flower:

Small rounded clusters at the end of stems that elongate as the plant matures. Flowers are about ¼ inch across, with 4 bright yellow spoon-shaped petals 3 to 5.5 mm long and 6 yellow stamens in the center.

Alternating with the petals are 4 yellow sepals about half as long as the petals. Flower stalks are green and hairless.

Leaves and stem:

Leaves are 1 to 3 inches (3 to 8 cm) long and to 1 inch wide, deeply divided into narrow lobes that may be further lobed or irregularly toothed, becoming smaller and less divided as they ascend the stem. Lower leaves are oblong with 5 to 7 pairs of lobes. Typically several stems ascend from the base; lower stems and the underside of leaves are sparsely to densely covered in short, bladder-like hairs.

Fruit:

Fruit is a slender pod to ½ inch (5 to 12 mm) long, straight or curved upward, with the brown stub of the style persisting at the tip.

Notes:

An infrequent non-weedy native species, occurrences are sparse across the south central parts of the state. The leaves may be confused with the non-native Dog Mustard (Erucastrum gallicum), which is stiffly hairy on leaves, stems and sepals, has flowers that are a pale yellow, and much longer fruits that are mostly straight. This species also lacks a basal rosette of leaves, which may further distinguish it from some other yellow mustards, and has what's known as vesicular hairs (hairs filled with fluid) especially along veins on the lower leaf surface, though these are not always present.