Abaxial: Underneath

Achene:  One-seed fruit, a fruit that looks like a seed.   Grass and sedge fruits are achenes.

Acropetal: Bottom-to-top, moving upward; opposite of basipetal

Adaxial: On top

Adventive: Introduced from another region and spread(ing) spontaneously

Anther:  Pollen-producing organ

                    (Also see floret illustration below)

Antrorse: Pointing forward (opposite of retrorse)

Apex: tip, top

Apical: near the tip

Auriculate: with "ears," term applied to leaf bases where two lobes reach around the culm

Awn:  Threadlike or needlelike tip on a lemma or glume

                            (Also see spikelet illustration)

Basal:  Near the base, opposite of apical

Basal Meristem:  The growing point of a grass, near its base.  See intercalary meristem

Basipetal: Toward the base, top-down, opposite of acropetal

Bract: Modified leaf associated with flowers.  Glumes, lemmas, and paleas are bracts.  The "scale" in the sedge spikelet is a bract.

Bristle:  A short stiff hair

Capitate: With a head (in trichomes, resembling a pin with a pinhead)

Cilia: Long stiff hairs

Ciliate: made of cilia

Collar: The region where the leaf sheath joins the leaf blade

Culm: Grass stem or stalk

Dehiscence:  Coming apart, separating (acropetal = from bottom up; basipetal = downward from the top)             

Disarticulation:  Separation, coming apart.   A term used in Eragrostis to describe the pattern of deterioration of the spikelet: acropetal (bottom up) or basipetal (top down)

Disarticulation: Separation, coming apart

Etuberculate: with no tubercles (warty projections, bumps)

Floret:  Lemma + palea + flower enclosed in the lemma/palea

Glabrous: Hairless

Glume:  The two bracts at the base of a spikelet are glumes.  They are below the florets.

Hirsute: With long soft hairs

Hispid: Bristly

Hypogynium:  Lobed or unlobed "platform" on the underside of most Scleria fruits

Inner glume: Second glume or upper glume

Intercalary meristem:  The growing point of a grass, near the base of the stem, aka basal meristem.  See Grass Biology link

Leaf sheath:  The basal portion of the leaf, wrapped around the culm

Lemma:  The lower, boat-shaped bract in the lemma-palea bract pair comprising the floret (containing the small flower)

Ligule:  Tiny flap of hairs or membrane (or both) rising from the top of the leaf blade where the blade joins the sheath (see photo below)

Lodicules:  Hidden in the lemma, tiny expanding bulbs at the base of the floret (these are the flower "petals"). Expansion of the lodicules opens the floret to expose the anthers and stigmas.

Lower glume: First glume

Mesoamerica: Mexico and Central America

Mucronate: with a small tooth hat the tip

Nodes: The thickened "joints" along the stem or culm

Outer glume: = first glume or lower glume

Palea:  The lid on the boat-shaped lemma, covering the flower within the lemma (see illustration at top of glossary)

Panicle (paniculate, adj.): An inflorescence where the branches are branched

Papilla: Bump, wart

Papillose: Bumpy, warty, with papillae

Pectinate:  Resembling a fish skeleton

Pedicellate: On a short stalk (pedicel), as in "pedicellate spikelet."  Compare with sessile.

Peduncle:  The stalk at the base of an inflorescence.  In Andropogon, the exposed stem (perhaps with small bracts on it) beneath a pair of rames.

Perianth: The organs surrounding a flower when there is no differentiation between sepals and petals, term often applied to Juncus and to various sedges

Perigynium:  Leafy sheath surrounding the ovary/achene in the sedge genus Carex.

Plano-convex:  Flat on one side and curved on the other. 

Pubescent: Hairy

Pulvinus (pl. pulvini): In the present context, the swollen joint at the base of a main inflorescence branch

Punctate: With tiny spots

Raceme (racemose, adj.):  An inflorescence where unbranched branches arise from a central axis

Rachilla: The axis of a spikelet (in some books spelled rhachilla)

Rachis:  The stem of a spike or raceme---the stem of a branch within an inflorescence

Rame: As used here, the ultimate branching unit, a term used mostly in Andropogon

Reticulate: With a network pattern, often seen on achene surfaces in sedges

Retrorse: Point toward the base (opposite of antrorse)

Rugose: Rough, wrinkled

Scabrous or scabrib: Rough, scratchy

Scale: A broad term.  In our usage, the scale in a sedge spikelet is a tiny bract associated with a flower.

Second glume: Upper glume

Septate: With cross-walls

Sessile: Attached with no stalk, as in "sessile spikelet" (compare with pedicellate)

Sheath: See leaf sheath

Spikelet:  Often resembling a bud, the unit made up of two glumes and one or more florets arranged along a rachilla (see illustration at the top of the glossary)

Stigma: The feathery pollen-receptive organ (see floret illustration above)

Stolon:  A thin horizontal stem

Tepal: A petal-like or sepal-like organ in a flower.  The term applies when sepals and petals are not differentiated.

Terete: round in cross-section. Terete leaves resemble knitting needles.

Tubercucle: Wart (Tuberculate = warty)

Tuberculate: Warty, bumpy, with warty projections

Upper glume: Second glume

Vein:  A visable vascular bundle

Viscid: Sticky, gummy