Great Yellow Wood Sorrel (Oxalis grandis)

Showy, colonial herbacious perennial from stout rhizomes; to 39" tall. Leaves are alternate, trifoliote with shamrock-like leaflets each 1-2.5" wide, edged with a maroon line; like typical Oxalis, but much larger. Flowers usually extend above the leaves, are yellow, 5 sepals and petals with traces of red in the center. 

Bloom Time: May - June.

Where found: Rich woods, East of the Mississippi River south of the Great Lakes to Georgia. In TN from the Cumberland Plateau eastward. Occasional. 


Note: Seven species of Oxalis are found in TN. The genus name Oxalis is from the Greek oxys for "sharp or sour", in reference to the flavor of the leaves, which contain sour-tasking oxalic acid. Plants of this genus have leaf blades divided into 3 leaflets, each notched and heart-shaped, forming a shamrock. The leaflets fold down at times, especially at night, as if protecting the plant.