This section is from the book "Harper's Guide To Wild Flowers", by Caroline A. Creevey. Also available from Amazon: Harper's Guide To Wild Flowers.
Family, Mustard. Color, white or greenish. Flowers similar to others of this Family. Pod, long, slender, upright, 2-valved by a thin partition. Stem, roughish, erect, simple (unbranched), 1 to 2 feet high. Leaves, long, narrow or oblong, partly clasping the stem by somewhat arrow or heart - shaped bases. May and June.
Wet places in the Middle States.
A, laevigata has root-leaves occasionally lyre-shaped, stem-leaves similar to those above. A smooth plant, taller than the last.
 
Continue to: