Erucastrum:  Answers to key questions leading to this genus

	petals yellow
	petals less than 7 mm long

Cruciferae: Answers to key questions leading to this family

	plants with two floral rings, and with each petal distinct from the other
	corolla regular
	4 petals
	calyx regular
	4 sepals
	stamens usually 6, four long and two short