Mexican primrose-willow, Ludwigia octovalvis

Mexican primrose-willow is a bushy herb or subshrub that grows in and near water. In addition to normal roots, it can develop swollen bunches of specialized roots that serve as floats. The flowers are an inch or more across. It has been used medicinally for headaches, swelling, arthritis, dysentery, or nervous diseases. It is now pantropical and its original home is unclear, but was likely in the Americas. With us it is in AL, FL, GA, HI, LA, MS, NC, SC, and TX. The USDA considers it native. Dixie Co FL, 10/20/15. Willow-herb family, Onagraceae.