Carex crebriflora
Carex crebriflora, the coastal plain sedge, is a species of flowering plant in the family Cyperaceae, native to Texas and the southeastern United States. It is typically found growing less than  above sea level in the understory of wet deciduous or mixed deciduous-evergreen forests, preferring alluvial, sandy soils. References

crebriflora
Endemic flora of the United States
Flora of Texas
Flora of the Southeastern United States
Plants described in 1922