Family: Cyperaceae
Schoenoplectus image
from USDA Plants website  
- spikelets in sessile clusters or open panicle

- spikelets round in cross-section,

- flowers perfect, bristles usually present

- stems triangular or circular in cross-section

- basal leaves few, cauline leaves one or none, all reduced to short projections

- inflorescence subtended by one erect and non-leafy bract, appearing as a continuation of the stem

- plants emergent

- stems round in cross-section

- inflorescenses branched

- spikelets pedunculate