Making It Grow - Melanthera nivea no widely used common name sometimes called showy squarestem although flowers aren't particularly prominent. In aster family and in my garden is at least three by
Melanthera nivea (Snow squarestem) | Native Plants of North America
Melanthera Nivea, Snow Square - uploaded by @treefrog44
Melanthera nivea (Asteraceae) image 135873 at PhytoImages.siu.edu
Melanthera nivea (L.) Small | Plants of the World Online | Kew Science
Melanthera, Snow Square Stem - Vincent Gardens
Melanthera nivea (L.) Small. A. Habit; B, C. Flowering and fruiting... | Download Scientific Diagram
Snow Squarestem
Melanthera nivea | Ecos del Bosque
Melanthera nivea - Wikipedia
NameThatPlant.net: Melanthera nivea
Melanthera nivea (Salt and Pepper/ Snow Squarestem) | Naturescapes of Beaufort, SC
Florida Native Plant Society (FNPS)
Photo of the leaves of Snow Squarestem (Melanthera nivea) posted by plantladylin - Garden.org