Arabis rhomboides.

Botanical name: 

ARABIS RHOMBOIDES, Mx. Meadow Cress. Equivalent of Water Cresses, the tuberous root edible as well as the leaves, similar to Radishes, taste like Cochlearia.

Medical Flora, or Manual of the Medical Botany of the United States of North America, Vol. 2, 1830, was written by C. S. Rafinesque.