Yellow Rocket

biennial or short-lived perennial, a mustard-like crucifer, common in Ozarks region, yellow flowers, leaves edible in winter and spring but bitter and very acrid, to the point of near-inedibility at other times, plant looks like small headed Italian broccoli (rapini) when just about to bloom, then turns gold-yellow with flowers, followed by abundant pods, a good winter green vegetable, same species as wintercress ({iB. vulgaris vulgaris})