The Vascular Flora of Clinton County, Ohio

Author Institution: Pembroke State College, Pembroke, North Carolin

Check list of scientific names of introduced agricultural grasses

no.34-11

A revision of the Houstonia pur-purea group (Rubiaceae)

Volume: 61Start Page: 157End Page: 18

Zizania

Plants annual or perennial; aquatic, usually rooted in the substrate; sometimes rhizomatous or stoloniferous; monoecious. Culms to 5 m, erect and emergent or floating. Leaves concentrated on the lower portion of the stem or evenly distributed; sheaths open, not inflated; ligules membranous or scarious, glabrous; pseudopetioles absent; blades flat, aerial or floating, scabrous or smooth. Inflorescences terminal panicles; branches usually unisexual, lower branches staminate, upper branches pistillate, middle branches sometimes with staminate and pistillate spikelets intermixed; pedicel apices cupulate; disarticulation beneath the spikelets, in cultivated strains disarticulation delayed, the spikelets tending not to shatter until harvested. Spikelets unisexual, with 1 floret. Glumes absent; calluses inconspicuous; lemmas 5-veined; paleas 3-veined; lodicules 2, membranous. Staminate spikelets pendant, terete or appearing so; lemmas membranous; paleas membranous, loosely enclosing the stamens; anthers 6. Pistillate spikelets terete; lemmas chartaceous or coriaceous, margins involute and clasping the margins of the paleas, apices acute to acuminate, sometimes awned, awns terminal, slender, scabridulous; styles 2, bases not fused, stigmas laterally exserted, plumose. Caryopses cylindrical; embryos linear, often as long as the caryopses; hila linear, x = 15