This tuberous species ("duck potato") is widespread across North, Central and South America. In Ky. it may be less frequent than the australis-brevirostra group, and concentrated in older ponds with more mature vegetation, but there has been frequent confusion among these species in the field. Although highly variable in its leaves, segregates have not been generally recognized in recent treatments. Beal et al. (1980) reported a high degree in interfertility. Records of var. obtusa (Engelm.) Wieg. are included here. Plants with hairy leaves are known as var. pubescens (Muhl. ex Nutt.) J.G. Sm., and are recognized by some authors as a distinct taxon of southeastern states (W), but no other diagnostic characters are known. There is a coll. referable to var. pubescens from CALL (MUR). S. latifolia is well know to have edible tubers, with much traditional human use.