- Family: bedstraw (Rubiaceae)
- Habitat: swamps, edges of streams and ponds
- Height: 3-10 feet
- Flower size: 1/3 inch flowers in spherical clusters 1-1/2 inches across
- Flower color: white
- Flowering time: June to August
- Origin: native
A flowerhead in bloom and another in bud. Photographed in Bucks County, Pennsylvania in early July.
A buttonbush twig. Note that the leaves may be opposite or in whorls of three.