Grasses and grass-like plants; graminoides.

Poaceae/Gramineae -> grass family

Cyperaceae -> sedge family

Juncaceae -> rush family

Contains about 8,500 species in approximatly 650 genera
Ecomomically important
Cereal grains: wheat; corn; rice; barley; rye; etc.
Forage for livestock
Turf for lawns; parks; athletic fields
Source of cover and food for wildlife
Source of construction materials and utensils

Vegetative grass structure
    Roots: adventitious and fibrous
    Stems: specialized types: rhizomes; stolons; runners
    Culm is the upright aerial stem

Recognition Characteristics:
    Jointed with swollen nodes; often hollow at the internodes
    Circular or ellipsoid in cross-section
    Leaves: 2-ranked
    Leaf consists of the blade; open sheath with ligule; auricles may be present
    on the blade; veination is parallel.

Reproductive structure

Inflorescence -> a spikelet which is a two-rankes cluster of florets (small flowers) typically subtended by a pair of glumes (sterile bracts).

Grass flower: adapted for wind or self pollination
    Lemma
    Palea
    Locicules
    Rachilla
    Awns
    Sterile lemma
    Sterile floret
    Stamens: 3 (1-6 or numerous)
    Carpels 3 (often appearing as 2) stigmas 2 (-3) plumose

Grass fruit: a grain or caryopsis

Examples of grasses that typify variation within the family members found in the Gulf Coast Region:

Arundinaria; Hydrochloa; Monanthochloe; Erianthus; Schizachrium; Andropogon; Phragmites; Ctenium; Spartina; Paspalum; Panicum; Zizaniopsis; Setaria; Manisuris; Chinochloa; Eragrostis; Briza; Aristida; Muhlenbergia.
 

Grass identification literature:

Worldwide: 6 genera, 400 species. Louisiana: 2 genera, 30 species.
Juncus and Luzula are two genera found in our region
Juncus: glabrous plants; capsules with many powderlike seeds
Luzula: hairy plants; capsules each with 3 seeds.

Vegetative features:

Herbs
Stems: round and solid, not jointed.
Leaves: 3-ranked, basal or along lower portion of the stem
Composed of a blade and a usually open sheath lacking a ligule
Blade linear, grass-like, may be reduced or absent

Reproductive features

Inflorescence highly branched, but often condensed and head-like
Inflorescence bract may be upright and appear as a continuation of the stem giving the appearance that the flowers are growing from one side of the stem.
i.e.: J. effusus; J. romerianus;

Flowers: 6 distinct perianth (tepals) parts, scale-like.
    Stamens: (3-) 6
    Pistil of three fused carpels; ovary superior

Placentation: parietal or axile
Fruit a capsule

Worldwide: 122 genera, 4500 species.
With approximately 240 species the family is the third most diverse family in the Louisiana after grasses, Poaceae, (360) and sunflowers, Asteraceae, (375).

Vegetative features:

Herbs, often rhizomatous
Stems: usually triangular in cross-section, solid, not jointed.
Leaves: 3-ranked, basal or along lower portion of the stem
Composed of a blade and a closed sheath, generally lacking a ligule
Blade linear, grass-like, may be reduced or absent

Reproductive features

Inflorescence a complex arrangement of small spikelets, usually subtended by bracts.
Flowers bisexual or unisexual, (plants monecious such as in Carex).
Each flower subtended by a scale-like bract.
Flowers: lacking a perianth (tepals) or composed of bristles, scales, or hairs
Stamens: 1-3 (-6)
Pistil of 2-3 fused carpels; ovary superior

Placentation: basal
Fruit an achene

Common genera and their recognition features:

Carex: flowers unisexual; monoecious; spikelets cylindrical and often composed of either pollen bearing
               or seed bearing flowers; pistil surrounded by a perigynium;

Scleria: perianth absent, achene white, bony in appearance, without a tubercle.

Fuirena: perianth of 3, stalked, scale-like or paddlelike structures; spikelets with scales spirally attached, usually in terminal umbels.

Elocharis: leaves lacking a blade; aerial stem unbranched, terminated by a single spikelet (spike); achene bearing a persistent tubercle.

Dichromena: Inflorescence subtended by leaflike bracts that are white at the base and green at the tips.

Rhynchospora: spikelets 1-2 flowered; achene bearing a persistent tubercle.

Bulbostylis: typically small plants with leaves capillary or filiform; spikelets many flowered, spiral; achene with a minute, persistent tubercle.

Cyperus: scales of spikelet two-ranked; perianth lacking; spikelets usually in head-like or umbel-like clusters; achenes lacking tubercles.

Cladium: stems 3 meters (ca. 10 ft.) tall; leaf blades 0.5-1 meter long, margins sharply saw-toothed; spikelets
                  in clusters on elongate inflorescences; spikelets one-flowered,; flowers without a perianth.

Fimbristsylis: spikelets several flowered, scales spirally arranged; spikelets arranged in terminal clusters or simple to compound umbelliform
                         cymes; perianth absent; unbranched part of the style is flattened and sometimes fimbriate; tubercle not persistent.

Scirpus: stems unbranched, triangular to essentially terete; in some species leaves bladeless; inflorescence variable, without bracts, with
                several leaflike bracts, with a single bract appearing like a continuation of the stem; spikelets many flowered, scales spirally arranged;
                perianth of 1-6 bristles; if style base persistent not tubercle-like.

    You may see Scirpus divided into the following genera: