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Deciduous: (1) [Leaves] {duration} Falling at the end of one growing season, as the leaves of non-evergreen trees; not evergreen. (Compare with evergreen and semi-evergreen.)

Deciduous: (2) [Seed cone armature] {persistence} Armature tending to fall off while the cone is otherwise still intact.

Decurrent: [Leaf bases, Leaflet bases]{shape}With the leaf base extending downward along the stem

Decussate: [Leaves] {insertion} Arranged along the stem in pairs, with each pair at right angles to the pair above or below; a form of opposite arrangement.

Deeply lobed: [Leaflets, Leaves, Petals, Sepals] {lobing} With lobes that are cut approximately = to > the distance to the midrib or base; deeply cleft.

Dehiscent: Splitting or forming one or more openings in a regular pattern at maturity enabling the contents to be released for dispersal, as certain fruits, such as capsules, that split open when ripe releasing seeds.

Deltoid: [Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Similar in shape to an equilateral triangle, with the point of attachment along one of the sides; like the Greek letter delta.

Dentate: [Leaf margins, Leaflet margins, Petal margins, Phyllary margins, Sepal margins] {form} Toothed along the margin, with pointed teeth that are directed outward rather than forward.

Denticidal capsule: [Fruits] {type} A capsule that opens (dehisces) at the apex, leaving a ring of teeth.

Denticulate: [Leaf margins, Leaflet margins] {form} Toothed along the margin, with very small, pointed teeth that are directed outward rather than forward; finely dentate.

Determinate inflorescence: An inflorescence in which the terminal or central flower opens first, halting further elongation of the main axis, as in cymes.

Diadelphous: of stamens united by the filaments into two fascicles

Diaphragmed: [Pith] {type} Uninterrupted by cavities but with regularly spaced partitions of denser tissue.

Dichotomous: dividing into two parts or groups

Dimorphic: having two forms

Dioecious: [Plants] {distribution of gender} Having functionally unisexual (i.e. separate male and female) flowers or cones, which are borne on different plants within the species; thus some plants are male and others are female.

Disarticulation: As the spikelets of grasses become mature, their floral scales (whether glumes and/or lemmas) become separated from their stems and fall to the ground. When the glumes (the lowermost scales) persist on their stems while the lemmas fall to the ground, this is referred to as 'disarticulation above the glumes.' When both glumes and lemmas separate from their stems and fall to the ground, this is referred to as 'disarticulation below the glumes.'

Disciform: of round or oval shape

Discoid: relating to or having a disk as a of a composite floret : situated in the floral disk : being a disk floret b of a composite flower head > having only tubular florets

Discoidal [Leaf lower surface, Leaf upper surface] {color variegation} A single large spot of color in the center of another.

Disk: the central portion of the flower head of a typical composite composed of closely packed tubular flowers

Disk floret: one of the tubular flowers in the disk of a composite plant

Dissected: deeply divided into many narrow segments (h)

Dissepiment: a separating tissue PARTITION SEPTUM

Distichous: [Leaves] {habit} With leaves arranged along the stem in two rows, the rows

Distinct: separate, not attached to like parts (h)

Dotted [Leaf lower surface, Leaf upper surface] {color variegation} The color disposed in very small round spots.

Doubly serrate: [Leaf margins, Leaflet margins] {form} Margin with teeth of two sizes (small teeth on the big teeth), the teeth bent toward the apex; doubly sawtoothed.

Drupe: [Fruits] {type} A fleshy fruit that does not split open at maturity (indehiscent), with a soft outer wall and one or more hard inner stone(s) each usually containing a single seed, as cherries and plums (Prunus).

Drupelet: one of the individual parts of an aggregate fruit (as the raspberry)

Duration: The length of time that a plant or any of its component parts exists.
opposite one other; two-ranked

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Edged: [Leaf lower surface, Leaf upper surface] {color variegation} One color is surrounded by a very narrow rim of another.

Ellipsoid: [Buds] {shape}; [Seed cones] {shape before opening, shape when open} Widest near the middle, with convex sides tapering equally toward rounded ends, and rounded in cross section; elliptic or oval-shaped in outline.

Ellipsoid-cylindric: [Buds] {shape}; [Seed cones] {shape before opening, shape when open} Intermediate in shape between ellipsoid and cylindric.

Elliptic: [Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Widest near the middle, with convex sides tapering equally toward both ends

Emarginate: [Leaf apices, Leaflet apices, Petal apices, Phyllary apices, Sepal apices] {shape} With a notch at the apex.

Endemic: restricted to or native to a particular area or region : INDIGENOUS -- used of kinds of organisms

Ensiform: [Leaflets, Leaves] {shape} Long and moderately slender, flat in cross section, gradually tapering to a pointed apex; sword-shaped; as an Iris leaf.

Entire: [Leaf margins, Leaflet margins, Petal margins, Phyllary margins, Sepal margins] {form} With relatively smooth margins that lack teeth, spines or other projections (the margins may be lobed); with a continuous margin.

Epidermal: of, relating to, or arising from the epidermis [which is] a layer of primary tissue in higher plants that is commonly one cell thick, often cutinized on its outer surface, and continuous in young plants except over the stomata, that provides protecti on to underlying parts against mechanical injury and desiccation, and that is largely replaced (as by periderm or exodermis) in older plants except on leaves and herbaceous stems

Epidermis: The outermost layer of cells of leaves, young stems and roots.

Epigynous: [Flowers] {perianth position} With the free portion of the perianth (the whorl of sepals and petals) borne at the top of a floral cup which is fused to and wholly encloses the ovary, the perianth thus appearing to arise from the top of the ovary.

Epiphytic: [Plants] {habit} Physically supported in its entirety by another plant through all or the major part of its life, but not drawing direct nutrition from the host plant.

Episepalous: growing on or adnate to the sepals

Equitant: [Leaves] {habit} With leaves clustered at the base of the stem and in two ranks, the sides overlapping at the base and often sharply folded along their midridge, as in Iris.

Erose: [Leaf margins, Leaflet margins, Petal margins, Phyllary margins, Sepal margins] {form} With the margin irregularly toothed, as if gnawed.

Estipulate: without stipules

Even-pinnate: [Terminal leaflet] {presence} Pinnately compound with an even number of leaflets, none truly terminal.

Evergreen: [Leaves] {duration} Bearing green leaves through the winter and into the next growing season; persisting two or more growing seasons; not deciduous.

Exfoliating: [Bark of mature trunks] {surface appearance} Bark splitting or cracking and falling away in thin patches or sheets, as in shagbark hickory (Carya ovata).

Exudate: exuded matter fr. exude : to ooze out slowly in small drops through openings (as pores) . . . b : to flow slowly out : issue slowly forth

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Falcate: [Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Long, arcing to one side and

Fan-shaped: [Leaflets, Leaves] {shape} Shaped like a fan, as a Gingko leaf.

Fascicle: [Inflorescences] {type} A tight cluster of stalked (pedicellate) flowers, the stalks originating very close to one another and diverging little if at all.

Fascicled: [Leaves] {insertion}; [Needles] {presence of clusters or fascicles} In a tight bundle, several leaves appearing to arise from a common point and diverging little if at all, as the needles of many pines (Pinus).

Fibrous: [Roots] {type} With several to many relatively slender roots of about the same diameter.

Filament: The stalk of a stamen, which supports an anther at its tip.

Filiform: [Leaflets, Leaves] {shape} Long and very slender, basically round in cross section and of uniform diameter; thread-like.

Flagellum: (pl. flagella) a long tapering process that projects singly or in groups from a cell or microorganism, is possibly equivalent to a much enlarged cilium, and is the primary organ of motion of flagellated protozoans and many algae, bacteria, and zoospores <.b>4 : a long slender shoot (as a stolon or runner) of a plant

Flaky: [Bark of mature trunks] {surface appearance} Bark with more or less regular, thin flakes, as in eastern hophornbeam (Ostrya vriginiana) and many pines (Pinus).

Fleshy: [Seed cone scales] {type} Fairly firm and dense, juicy or at least moist, and easily cut.

Floral: upon, within, or associated with the flowers.

Floral Bracts: A compound flower often has floral bracts that circumscribe its base, particularly among members of the Asteraceae (Aster family). These scale-like bracts surround the ovaries of the flower and they are often appressed together. They are often referred to as 'involucral bracts' or 'phyllaries' by botanical authorities.

Floral cup: A cup or tube usually formed by the fusion of the basal parts of the sepals, petals and/or stamens, and on which they are seemingly borne; surrounds the ovary, or ovaries, and may be fused wholly, partly or not at all to them; the shape varies from disc-like to cupshaped,flask-like or tubular; a hypanthium.

Floret: A very small, structurally specialized flower, especially those of the grasses (Poaceae) and the sunflower family (Asteraceae).

Flower: The reproductive structure in flowering plants (angiosperms), consisting of stamens and/or pistils, and usually including a perianth of sepals and/or petals.

Follicle: [Fruits] {type} A usually dry fruit, with one interior chamber or locule, and splitting open (dehiscing) lengthwise along a single line, as in milkweed (Asclepias). [

Forbs: These are plants that produce flowers with conspicuous petals and/or sepals; the flowers of such plants are often showy and insect-pollinated. In contrast, grasses (Poaceae), sedges (Cyperaceae), and miscellaneous other plants are not forbs because their wind-pollinated flowers lack petals and sepals, or their petals and sepals are tiny and inconspicuous. Such wind-pollinated flowers are not very showy, although there are some exceptions.

Four-angled: [Leaf cross section] {shape} More or less diamond-shaped in cross section.

Four-ranked: [Leaves] {habit} With leaves arranged in along the stem in four rows.

Free-central: [Placentation] {type} Attachment of ovules to a free-standing central axis in a compound ovary which has a single inner compartment (unilocular), and thus no interior partitions (septa).

Fruit: The seed-bearing structure in flowering plants, consisting of one or more matured or ripened pistil(s), along with any persisting accessory parts such as sepals or receptacle.

Funnelform: A corolla that is shaped like a funnel, being narrow and tubular at the base, but flaring outward toward the outer margin. The corollas of Ipomoea spp. (Morning Glories) and Calystegia spp. (Bindweeds) are funnelform.

Furrowed: [Bark of mature trunks] {surface appearance} Bark with relatively long narrow depressions or grooves, as in tulip-tree (Liriodendron tulipifera).

Fusiform: [Buds] {shape} Elongate, broadest at the middle, evenly tapering to either end, and rounded in cross section; spindle-shaped.

Fusion: The physical connection of equivalent or dissimilar structures, as fused sepals or petals.

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Gametophyte: the individual or generation of a plant exhibiting alternation of generations that bears sex organs, constitutes the major part of the plant body in most algae, fungi, and mosses, exists as an independent transitory thalloid body in ferns and related plants, and is reduced to a microscopic or rudimentary structure in see plants -- distinguished from sporohphyte

Geminate: In pairs, as a leaf which is divided into two leaflets.

Germination: The beginning or resumption of growth by a seed, bud or other structure.

Glabrate: [2-4-year-old twigs, Buds, Leaf lower surface, Leaf upper surface, Petals, Petioles, Phyllaries, Rachises, Sepals, Young twigs] {pubescence} Becoming glabrous; almost glabrous; pubescent when young, but losing the hairs in maturity.

Glabrous: [2-4-year-old twigs, Buds, Leaf lower surface, Leaf upper surface, Petals, Petioles,Phyllaries, Rachises, Sepals, Young twigs] {pubescence} Lacking plant hairs (trichomes).

Glandular: (1) [Petioles, Rachises] {special surface features} Bearing secreting organs, or glands.

Glandular: (2) [Stipules] {type} In the form of a secreting organ or gland. blade-like, scale-like and spinose.)

Glaucous: [Buds, Young twigs, Leaves] Covered with a whitish or bluish waxy coating (bloom) that can sometimes be rubbed off.

Globose: [Buds] {shape}; [Seed cones] {shape before opening, shape when open} Circular in cross section and in outline when viewed from any angle; like a globe or sphere.

Glochid: glochidium : a barbed hair or spine (as on the massulae of a water fern or on some cacti)

Glomerule: [Inflorescences] {type} A dense cluster of flowers.

Glossy: Lustrous or shiny, as the upper surface of southern magnolia (Magnolia grandiflora) leaves.

Glume: one of the two empty bracts at the base of the spikelet in grasses

Glutinous: Gluey, sticky or gummy; covered with sticky exudates.

Grain: A grain is a seed with a hard coat. It typically refers to the seeds of grasses (Poaceae). Sometimes this term refers to a particle of pollen (e.g., a grain of pollen).

Grass: Members of the Poaceae (Grass family) are true grasses.

Grass-like herbaceous: [Plants] {habit} Herbaceous with relatively long, narrow leaves appearing similar to those of grasses (Poaceae).

Grooved: [Apophyses] {texture} With a narrow depression or groove.

Gymnosperm: [Plants] {major group} A seed plant which produces seeds that are not enclosed inside an ovary, as the conifers.

Gynecandrous: This refers to a spikelet that has pistillate (female) flowers above the staminate (male) flowers. Some sedges (e.g., Carex spp.) have this arrangement of flowers on the same spikelet.


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