Xyris difformis, the bog yelloweyed grass, is a North American species of flowering plant in the yellow-eyed-grass family. It is native to the eastern and southern United States, eastern and central Canada, and Central America.Biota of North America Program 2014 county distribution map
Xyris difformis is a perennial herb up to 90 cm (3 feet) tall with grass-like leaves up to 50 cm (20 inches) long, and yellow flowers.of North America, Xyris difformis Chapm. 1860. Chapman, Alvan Wentworth 1860. Flora of the southern United States 500
Varieties Xyris difformis var. curtissii (Malme) Kral - Belize, coastal states of USA from Texas to Virginia Xyris difformis var. difformis - Nova Scotia, Ontario, USA (coastal states from Maine to Texas plus areas as far inland as Michigan, Oklahoma, Indiana, and Arkansas) Xyris difformis var. floridana Kral - Belize, Honduras, Nicaragua, USA (coastal states from Louisiana to the Carolinas)
References
External links Photo of herbarium specimen at Missouri Botanical Garden, collected in Virginia in 1980