Important features of this reproductive pattern are rapid development, early maturity, and the allocation of much energy into many small propagules. R. maritima s.s. produces enormous numbers of drupelets about two weeks after first flowering because the many inflorescences are efficiently self-pollinated. The dark brown or black drupelets are 0.5-4 mm long, and vary from obliquely ovoid or rounded to asymmetrical, flattened, and beaked. Salinity may control drupelet size and shape, and drupelets produced in early summer can have a thicker coat than those from the same plant in early fall. Drupelets are attached to slender pedicels that vary in form depending on water conditions.
Pedicels are always longer than the drupelets.
An elliptic or triangular perforation occurs near the base of the beak. A fully-pollinated and mature inflorescence usually consists of eight pedicellate drupelets atop a straight or coiled peduncle. Ripe drupelets are transported short distances in floating vegetation, considerable distances by wind and in the guts of fishes, and long distances in the digestive tracts of waterfowl. Wigeongrass drupelets mix with small amounts of other plant material, forming compact balls up to the size of small watermelons - these are often found along the beaches of saline lakes in windy locations. Water permanency, water depth, depth distribution of drupelets in sediment, sediment chemistry, and water column chemistry can influence drupelet distribution and germination and interact with temperature effects.