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Term Definition
1 Accessory fruit[Fruits] {type} A fruit or group of fruits that ripen together and include some accessory tissue (i.e. structures not derived from the pistil) such as the thickened hypanthium of a rose (Rosa) hip or the fleshy receptacle of a strawberry (Fragaria). [modified from W&K, p. 585]
2 Accessory parts of fruitsStructures consisting of, or derived from, floral parts other than the pistil, such as sepals, hypanthium or receptacle.
3 Achene[Fruits] {type} A more or less small, dry fruit that does not split open at maturity (indehiscent), with a typically thin, close-fitting wall surrounding a single seed. [modified from Z p. 357]
4 Acicular[Leaflets, Leaves] {shape} Very long and slender, gradually tapering to a point, like a needle; needle-shaped. (Compare with awl-shaped, filiform and linear.) [modified from K&P, p. 11]
5 Acorn[Fruits] {type} A nut with a persistent, cup-like structure (cupule) attached at the base consisting of numerous partially fused, overlapping, dry bracts, as in oaks (Quercus). [modified from K&P, p. 11]
6 Acuminate[Leaf apices, Leaflet apices, Petal apices, Phyllary apices, Sepal apices] {shape} Gradually tapering to a sharp point, forming concave sides along the tip. (Compare with acute.) [modified from H&H, p. 153]
7 Acute[Leaf apices, Leaflet apices, Petal apices, Phyllary apices, Sepal apices] {shape} Tapering to a pointed apex with more or less straight sides, the sides coming together at an angle of less than 90 degrees. (Compare with acuminate and obtuse.) [modified from H&H, p. 153]
8 Adventitious (1)Structures or organs arising in a position that is unusual for their type, as roots originating on the stem. [modified from H&H, p. 5]
9 Adventitious (2)[Roots] {type} Roots arising from any part of the plant (e.g. stem or leaf) other than the root system; usually growing laterally, often from the lower part of the main stem. [modified from Z p. 358]
10 Aerial stem[Stems] {type} A prostrate to erect, above ground stem. [modified from W&K, p. 30]
11 Aggregate fruit[Fruits] {type} A cluster of fruits that stick together or are fused, originating from two or more separate pistils contained within a single flower, as in blackberry (Rubus). (Compare with multiple fruit.) [modified from H&H, p. 6]
12 Alternate[Leaves] {insertion} Positioned singly at different heights on the stem; one leaf occurring at each node. (Compare with opposite and whorled.) [modified from L, p. 738]
13 AndroeciumA collective term for all the stamens and any closely associated structures in a flower. [modified from W&K, p. 585]
14 Angiosperm[Plants] {major group} Plants that bear their seeds enclosed in an ovary; the flowering plants. (Compare with gymnosperm.)
15 Annual[Plants] {life span} Normally living one year or less; growing, reproducing, and dying within one cycle of seasons. [K&P, p. 15]
16 AntherThe pollen-producing portion of the stamen typically borne at the tip of a stalk or filament. [modified from Z p. 358]
17 ApexThe portion of a plant structure (such as a leaf, bud, stem, etc.) farthest from its point of attachment or uppermost; the tip. (Compare with base.) [modified from H&H, p. 10]
18 Apical[Placentation] {type} Attachment of ovules at the top or apex of the ovary. (Compare with basal placentation.) [modified from Z p. 359]
19 Apiculate[Leaf apices, Leaflet apices, Petal apices, Phyllary apices, Sepal apices] {shape} Ending abruptly in a small, slender, point that is not stiff and often slightly curved. (Compare with aristate, caudate and mucronate.) [modified from H&H, p.153]
20 Apopetalous[Corolla] {fusion} With petals distinct, not fused. (Compare with sympetalous.) [modified from K&P, p. 16]
21 ApophysisThe outer portion of a cone scale which is exposed when the cone is closed. [modified from H&H, p. 10]
22 Aposepalous[Calyx] {fusion} With sepals distinct, not fused. (Compare with synsepalous.) [modified from K&P, p. 16]
23 Appressed[Leaves, Petals, Phyllaries, Sepals] {vertical orientation} Pressed upwardly close or flat against the bearing structure, thus more or less parallel to it. (Compare with ascending, reflexed and spreading.) [modified from K&P, p. 16]
24 Aquatic-emergent[Plants] {habit} Growing in water with stem and leaves extending above the surface. (Compare with aquatic-floating and aquatic-submerged.)
25 Aquatic-floating[Plants] {habit} Growing in water with leaves floating on the surface. (Compare with aquatic-emergent and aquatic-submerged.)
26 Aquatic-submerged[Plants] {habit} Growing in water with stem and leaves beneath the surface. (Compare with aquatic-emergent and aquatic-floating.)
27 Arachnoid[Buds, Leaf lower surface, Leaf upper surface, Phyllaries, Sepals, Young twigs] {pubescence type} With fairly sparse, fine, white, loosely tangled hairs; cobwebby. [modified from K&P, p. 17]
28 Aristate[Leaf apices, Leaflet apices, Petal apices, Phyllary apices, Sepal apices] {shape} Bearing a prolonged, slender, stiff, usually straight tip; awned or bristled. (Compare with apiculate, caudate and mucronate.) [modified from K&P, p. 18]
29 ArmatureAny kind of sharp defense such as thorns, spines, or prickles. [modified from L, p. 739]
30 Armed (1)[Bark of mature trunks] {surface appearance} Bearing any kind of sharp defense such as thorns, spines, or prickles. [modified from L, p. 739]
31 Armed (2)[Seed cone scales] {armature} Bearing a hook, prickle or other sharply pointed structure on the end of the cone scale.
32 Ascending[Leaves, Petals, Phyllaries, Sepals] {vertical orientation} Spreading at the base and then curving upward to an angle of 45 degrees or less relative to the bearing structure. (Compare with appressed, reflexed and spreading.) [modified from K&P, p. 18]
33 Asymmetric (1)[Calyx, Corolla] {symmetry} Not divisible into essentially equal halves along any plane. (Compare with bilaterally symmetric and radially symmetric.) [modified from K&P, p. 18]
34 Asymmetric (2)[Seed cones] {symmetry} Not divisible into essentially equal halves along any plane. (Compare with nearly symmetric and symmetric.) [modified from K&P, p. 18]
35 Attenuate[Leaf bases, Leaflet bases] {shape} Tapering gradually to a narrow base. [H&H, p. 150]
36 Auriculate[Leaf bases, Leaflet bases] {shape} With ear-shaped appendages at the base. [modified from H&H, p. 150]
37 Autotrophic[Plants] {nutrition} Able to synthesize the nutritive substances an organism needs from the non-living environment; in plants, photosynthetic. (Compare with parasitic.) [modified from REE, p. 891]
38 Awl-shaped[Leaflets, Leaves] {shape} Narrowly triangular and sharply pointed, like an awl. (Compare with acicular and ensiform.) [modified from H&H, p. 150]
39 AwnA slender, more or less straight and stiff, fine-pointed appendage; may be located at the tip of a leaf or bract and a continuation of the midvein, or comprising the pappus in fruits of the sunflower family (Asteraceae). [modified from K&P, p. 19 & W&K, p. 587]
40 AxilThe point of the upper angle formed between the axis of a stem and any part (usually a leaf) arising from it. [H&H, p. 13]
41 Axile[Placentation] {type} Attachment of ovules at or near the center of a compound ovary which has more than one inner compartment (multilocular), the ovules located on the inner angle formed by the interior partitions (septa). (Compare with free-central placentation.) [modified from Z pp. 359-60]
42 Axillary[Buds, Inflorescences, Seed cones] {position} On the stem just above the point of attachment of a leaf (or leaf scar) or branch; borne in the axil of a leaf or branch. (Compare with terminal.) [modified from W&K, p. 32]
43 AxisAny relatively long, continuous, supporting structure that typically bears other organs laterally, and represents the main line of growth and/or symmetry; as a stem that bears leaves or branches, or the rachis of an inflorescence that bears flowers along its length. [modified from K&P, p. 19 & H&H, p. 13]
44 Banded[Leaf lower surface, Leaf upper surface] {color variegation} Transverse, or horizontal, stripes of one color crossing another. (Compare with striped.) [modified from RDMB, p. 150]
45 BarkThe outermost layer of a woody stem, usually with one or more corky layers that prevent water loss and protect the inner living tissues from mechanical damage. [modified from W&K, p. 587]
46 Basal (1)At or very near the base of a plant structure. [modified from K&P, p. 20]
47 Basal (2)[Leaves] {position} With leaves arising at or near the base of the stem. (Compare with cauline.) [modified from H&H, p. 162]
48 Basal (3)[Placentation] {type} Attachment of ovules at the base of the ovary. (Compare with apical placentation.) [modified from Z p. 360]
49 BaseThe portion of a plant structure (such as a leaf, bud, stem, etc.) nearest the point of attachment or lowermost; the bottom. (Compare with apex.)
50 Berry[Fruits] {type} A fleshy fruit that does not split open at maturity (indehiscent), with few or more seeds (rarely just one), the seeds without a stony covering; the flesh may be more or less homogenous or with the outer portion more firm or leathery; as grapes (Vitis). (Compare with drupe.) [modified from Z p. 360]
51 Biennial[Plants] {life span} Normally living two years; germinating or forming and growing vegetatively during one cycle of seasons, then reproducing sexually and dying during the following one. [K&P, p. 21]
52 Bifoliolate[Leaves] {complexity form} Compound with two leaflets; two-leafleted or geminate. (Compare with bigeminate and trifoliolate.) [modified from W&K, p. 587]
53 Bigeminate[Leaves] {complexity form} With two orders of leaflets, each divided into pairs or geminately compound; doubly paired. (Compare with bifoliolate.) [modified from RDMB, p. 94, modified; H&H, p. 16]
54 Bilaterally symmetric[Calyx, Corolla] {symmetry} Divisible into two essentially equal portions along only one plane. (Compare with asymmetric and radially symmetric.) [modified from K&P, p. 120 (see zygomorphic)]
55 Bipalmately compound[Leaves] {complexity form} With two orders of leaflets, each palmately compound; twice palmately compound. (Compare with once palmately compound and tripalmately compound.) [modified from RDMB, p. 94]
56 Bipinnate-pinnatifid[Leaves] {complexity form} Twice pinnately compound with pinnatifid leaflets. (Compare with once pinnate-pinnatifid and tripinnate-pinnatifid.)
57 Bipinnately compound[Leaves] {complexity form} With two orders of leaflets, each pinnately compound; twice pinnately compound. (Compare with once pinnately compound and tripinnately compound.) [modified from RDMB, p. 94]
58 Bipinnately lobed[Leaves] {lobing form} With two orders of leaf lobing, each pinnately lobed; twice pinnately lobed. (Compare with once pinnately lobed and tripinnately lobed.)
59 Bisexual (1)Having functional reproductive structures of both sexes (i.e. male and female) in the same flower or cone. (Compare with unisexual.) [modified from K&P, p. 21]
60 Bisexual (2)[Flowers] {gender} Having functional reproductive structures of both sexes (i.e. male and female) in the same flower. (Compare with unisexual.) [modified from K&P, p. 21]
61 Biternate[Leaves] {complexity form} With two orders of leaflets, each divided into threes or ternately compound; twice trifoliolate. (Compare with trifoliolate and triternate.) [modified from RDMB, p. 94]
62 BladeThe flat, expanded portion of a leaf, petal, sepal, etc. [modified from RDMB, p. 93]
63 Blade-like[Stipules] {type} Expanded and flattened, as the main portion or blade of a broad leaf. (Compare with glandular, scale-like and spinose.)
64 Blotched[Leaf lower surface, Leaf upper surface] {color variegation} The color disposed in broad, irregular blotches. [RDMB, p. 150]
65 Bordered[Leaf lower surface, Leaf upper surface] {color variegation} One color is surrounded by an edging of another. (Compare with edged.) [modified from RDMB, p. 150]
66 BractA modified, usually reduced leaf, often occurring at the base of a flower or inflorescence. [modified from H&H, p. 18]
67 BranchA division or subdivision of a stem or other axis. [modified from H&K, p. 6]
68 BranchletAn ultimate branch, i.e. one located at the end of a system of branches; a small branch. (Compare with twig.) [modified from K&P, p. 22]
69 BristleA slender, more or less straight and stiff, fine-pointed appendage; may be located at the tip of a leaf or bract and a continuation of the midvein, or comprising the pappus in fruits of the sunflower family (Asteraceae). [modified from K&P, p. 22 & W&K, p. 587 (see awn)]
70 Broad-leaved[Leaves] {general form} With leaves that are not needle-like or scale-like, but having relatively broad, flat surfaces, as in most deciduous trees such as maples (Acer) and hickories (Carya). (Compare with needle-like and scale-like.)
71 Broadleaf herbaceous[Plants] {habit} Herbaceous with relatively broad leaves, thus differing from the long, narrow leaves of grasses (Poaceae) and other grass-like plants . (Compare with grass-like herbaceous.)
72 BudAn immature shoot, either vegetative, floral or both, and often covered by protective scales. [modified from RDMB, p. 88]
73 Bulb[Stems] {type} A short, vertical, usually underground stem with fleshy storage leaves attached, as in onions (Allium cepa). (Compare with corm.) [W&K, p. 588, modified.]
74 Bundle scarA small scar within a leaf scar left by a vascular bundle that previously entered the stalk (petiole) or base of the fallen leaf. [modified from W&K, p. 588]
75 Bur[Fruits] {type} A cypsela or other fruit enclosed in a whorl of dry bracts (involucre) covered with spines or prickles that are often hooked, aiding in their dispersal by animals, as in cocklebur (Xanthium). [modified from RDMB, p. 111, H&H, p. 19, & H&K, p. 6]
76 Caducous[Petals, Sepals, Stipules] {persistence} Falling off very early, as stipules that drop soon after the leaf develops. (Compare with persistent.) [modified from Z p. 361]
77 CalyxThe collective term for all of the sepals of a flower; the outer perianth whorl. (Compare with corolla.) [modified from H&H, p. 20]
78 Canescent[Buds, Leaf lower surface, Leaf upper surface, Phyllaries, Sepals, Young twigs] {pubescence type} Gray or white in color due to a covering of short, fine, gray or white hairs. [H&H, p. 165]
79 Capsule[Fruits] {type} A dry fruit that opens (dehisces) in any of various ways at maturity to release few to many seeds. [modified from Z p. 362]
80 Carnivorous[Plants] {carnivory} Capturing animals (usually insects), digesting their tissues and assimilating the digested substances as nourishment, especially nitrogen. [modified from K&P, p. 25]
81 CarpelThe basic ovule-bearing unit of flowers, thought to be evolutionarily derived from an infolded leaf-like structure; equivalent to a simple pistil or a division of a compound pistil. [modified from K&P, p. 25]
82 Caryopsis[Fruits] {type} A more or less small, dry fruit that does not split open at maturity (indehiscent), with a thin wall surrounding and fused to the single seed, as the fruits of the grass family (Poaceae); a grain. [modified from Z p. 362 & H&H, p. 22]
83 Catkin[Inflorescences] {type} A pendent, more or less flexible, spike-like inflorescence with numerous small flowers, typically of only one sex (unisexual), lacking petals and subtended by scaly bracts, as in willows (Salix) and birches (Betula); catkins are often wind pollinated and fall as a unit after flowering or fruiting. [modified from Z p. 358 (see ament)]
84 Caudate[Leaf apices, Leaflet apices, Petal apices, Phyllary apices, Sepal apices] {shape} Ending in a long, tapering, straight or curved, flexible tip; tailed. (Compare with apiculate, aristate and mucronate.) [modified from K&P, p. 26]
85 Cauline[Leaves] {position} With leaves positioned along the stem above ground level. (Compare with basal.) [modified from H&H, p. 162]
86 Chambered[Pith] {type} Interrupted by more or less regularly spaced cavities. (Compare with continuous, diaphragmed and hollow.) [modified from K&P, p. 27]
87 Checkered[Bark of mature trunks] {surface appearance} Bark divided into small squarish plates, resembling alligator leather, as in flowering dogwood (Cornus florida). (Compare with plated and warty.) [modified from C&A, pp. 1-3]
88 Ciliate[Leaf margins, Leaflet margins, Petal margins, Phyllary margins, Sepal margins] {form}; [Buds] {pubescence type} With a fringe of hairs along the margin. [modified from H&H, p. 24]
89 Circular[Leaf cross section] {shape} Round in cross section.
90 Circumferential[Stipules, Stipule scars] {extent} Encircling the twig.
91 Circumscissile capsule[Fruits] {type} A capsule that splits open (dehisces) by a horizontal line around the fruit, the top coming off as a lid. [modified from Z p. 362]
92 Clasping[Leaf bases, Leaflet bases] {shape} The base partly surrounding the stem. [modified from RDMB, p. 134]
93 Clawed[Petals] {shape}
94 Cleft[Petal apices] {shape}
95 Clouded[Leaf lower surface, Leaf upper surface] {color variegation} Colors are unequally blended together. [RDMB, p. 150]
96 Clustered[Leaves] {insertion}; [Needles] {presence of clusters or fascicles} Leaves grouped closely together at the point of attachment and tending to diverge from one another, as the leaves on short shoots in Gingko (Gingko biloba) or the needles on short shoots in larches (Larix). (Compare with fascicled and solitary.) [modified from K&P, p. 29]
97 Collateral[Buds] {position} In pairs, within or straddling the leaf axils; often located on either side of an axillary bud. (Compare with superposed.) [modified from K&P, p. 30]
98 Compound[Leaves] {complexity} Divided into two or more equivalent parts, as a leaf that consists of multiple, distinct leaflets; not simple. [modified from K&P, p. 31]
99 Compound dichasium[Inflorescences] {type} A determinate, cymose inflorescence with the main axis bearing a terminal flower and a pair of opposite or nearly opposite lateral branches, each branch also bearing a terminal flower and a pair of lateral flowers or branches; a branched dichasium. (Compare with cyme and simple dichasium.) [modified from K&P, p. 38]
100 Compound ovaryAn ovary formed by the fusion of the bases of two or more carpels; recognizable by the presence of more than one area of placentation, locule, ovary lobe, style (or style branch), or stigma. (Compare with simple ovary.) [modified from W&K, p. 590]
101 Compound umbel[Inflorescences] {type} An inflorescence composed of several branches that radiate from almost the same point, like the ribs of an umbrella, each terminated by a secondary set of radiating branches that end in one or more flowers, the upper surface of the whole inflorescence rounded, or more or less flat; a branched umbel; as in Queen Anne’s lace (Daucus carota). (Compare with simple umbel.) [modified from Z p. 388]
102 ConeReproductive structures in conifers comprised of scales and/or other types of modified leaves densely arranged on a central stalk; female, or seed cones, bear ovules on the surface of their scales; male cones produce pollen.
103 Conic[Buds] {shape}; [Seed cones] {shape before opening, shape when open} Rounded in cross section, broadest at the base and essentially triangular in outline; cone-shaped. [modified from K&P, p. 32]
104 ConiferCone-bearing plants, such as pines (Pinus).
105 Conspicuous lenticels[Bark of mature trunks] {surface appearance} Bark with readily visible pores or lenticels, as in many of the birches (Betula).
106 Continuous[Pith] {type} Uninterrupted by cavities and essentially homogenous in texture; solid. (Compare with chambered, diaphragmed and hollow.) [modified from K&P, p. 32]
107 Cordate[Leaf bases, Leaflet bases, Leaflets, Leaves] {shape} Heart-shaped, with the notch at the base. [H&H, p. 150]
108 Corm[Stems] {type} A short, solid, vertical, usually underground, enlarged stem with leaves that are dry and scale-like or absent. (Compare with bulb.) [W&K, p. 31, modified.]
109 CorollaThe collective term for all of the petals of a flower; the inner perianth whorl. (Compare with calyx.) [modified from H&H, p. 31]
110 Corymb[Inflorescences] {type} A racemose inflorescence with the individual flower stalks (pedicels) progressively shorter toward the apex so the flowers are all at about the same level, forming a flat or rounded surface across the top. (Compare with simple umbel.) [modified from K&P, p. 33]
111 Crenate[Leaf margins, Leaflet margins, Petal margins, Phyllary margins, Sepal margins] {form} With rounded teeth along the margin; scalloped. (Compare with crenulate, dentate and serrate.) [modified from H&H, p. 157]
112 Crenulate[Leaf margins, Leaflet margins] {form} With very small, rounded teeth along the margin; finely crenate or small-scalloped. (Compare with crenate, denticulate and serrulate.) [modified from H&H, p. 157, K&P, p. 34]
113 Crisped[Leaf margins, Leaflet margins] {form} Margins divided and twisted in more than one plane, as parsley (Petroselinum crispum) leaves; curled. [modified from RDMB, p. 137 (see crispate)]
114 Cuneate[Leaf bases, Leaflet bases] {shape} Wedge-shaped and tapering to a point at the base. [H&H, p. 150]
115 CupuleA cup-like structure at the base of some fruits, such as the acorns of oaks (Quercus), composed of a persistent, usually dried, whorl of bracts (involucre) or other sterile floral parts, that are often partially fused. [modified from L, p. 747, & K&P, p. 35]
116 Cyathium[Inflorescences] {type} An inflorescence consisting of a single, naked, terminal pistillate flower with several tiny, naked, lateral staminate flowers, the whole more or less enclosed by a cuplike whorl of bracts (involucre) and resembling a single flower; as in poinsettias (Euphorbia). [modified from K&P, p. 36]
117 Cylindric[Buds] {shape}; [Seed cones] {shape before opening, shape when open} Rounded in cross section with a more or less uniform diameter and blunt ends; cylinder-shaped. [modified from K&P, p. 36]
118 Cyme[Inflorescences] {type} Generally, a determinate, compound, and frequently more or less flat-topped inflorescence; the basic cymose unit is a three-flowered cluster composed of a main stalk bearing a terminal flower and below it, two stalked, lateral flowers, each with a reduced leaf or bract at the base. (Compare with compound dichasium, helicoid cyme, scorpioid cyme and simple dichasium.) [modified from Z p. 365]
119 CymoseIn the form of a simple or compound cyme; bearing cymes. [modified from H&K, p. 11]
120 Cypsela[Fruits] {type} A dry, one-seeded fruit that does not split open at maturity (indehiscent), with persistent perianth tissue (pappus) attached at the top, as in some members of the sunflower family (Asteraceae). [modified from H&H, p. 35]
121 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.) [modified from L, p. 748]
122 Deciduous (2)[Seed cone armature] {persistence} Armature tending to fall off while the cone is otherwise still intact. (Compare with persistent.)
123 Decurrent[Leaf bases, Leaflet bases] {shape} With the leaf base extending downward along the stem. [modified from RDMB, p. 134]
124 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. [modified from H&H, p. 162]
125 Deeply lobed[Leaflets, Leaves, Petals, Sepals] {lobing} With lobes that are cut approximately 1/2 to 3/4 the distance to the midrib or base; deeply cleft. (Compare with divided, moderately lobed and shallowly lobed.) [modified from RDMB, p. 137 (see parted) & H&H, pp. 157-58 (see parted)]
126 DehiscentSplitting 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. (Compare with indehiscent.) [modified from K&P, p. 37 & W&K, p. 591]
127 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. (Compare with cordate and obdeltoid.) [modified from H&H, p. 150]
128 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. (Compare with crenate, denticulate and serrate.) [modified from H&H, p. 157]
129 Denticidal capsule[Fruits] {type} A capsule that opens (dehisces) at the apex, leaving a ring of teeth. [modified from RDMB, p. 110]
130 Denticulate[Leaf margins, Leaflet margins] {form} Toothed along the margin, with very small, pointed teeth that are directed outward rather than forward; finely dentate. (Compare with crenulate, dentate and serrulate.) [modified from H&H, p. 157, & K&P, p. 37]
131 Determinate inflorescenceAn inflorescence in which the terminal or central flower opens first, halting further elongation of the main axis, as in cymes. (Compare with indeterminate inflorescence.) [modified from Z p. 366]
132 Diaphragmed[Pith] {type} Uninterrupted by cavities but with regularly spaced partitions of denser tissue. (Compare with chambered, continuous and hollow.) [modified from K&P, p. 38]
133 Dichotomous[Leaf venation, Leaflet venation] {form} With veins forking into more or less equal pairs, as in Gingko leaves. (Compare with palmate, parallel, pinnate and reticulate venation.) [modified from W&K, p. 591]
134 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. (Compare with monoecious and synoecious.) [modified from K&P p. 39]
135 Discoidal[Leaf lower surface, Leaf upper surface] {color variegation} A single large spot of color in the center of another. (Compare with dotted and spotted.) [modified from RDMB, p. 150]
136 Distichous[Leaves] {habit} With leaves arranged along the stem in two rows, the rows opposite one other; two-ranked. (Compare with three-ranked and four-ranked.) [modified from K&P, p. 40]
137 Divided[Leaflets, Leaves, Petals, Sepals] {lobing} Cut or split almost to the midrib or base. (Compare with deeply lobed, moderately lobed and shallowly lobed.) (Please note that the word “divided” as used here to describe a particular type of lobing, has a narrower meaning than the general sense of the word used elsewhere in this glossary.) [modified from H&H, p. 157]
138 Dotted[Leaf lower surface, Leaf upper surface] {color variegation} The color disposed in very small round spots. (Compare with discoidal and spotted.) [modified from RDMB, p. 150]
139 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. (Compare with serrate.) [modified from W&K, p. 38]
140 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). (Compare with berry.) [modified from K&P, p. 41]
141 DurationThe length of time that a plant or any of its component parts exists. [RDMB, p. 87]
142 Edged[Leaf lower surface, Leaf upper surface] {color variegation} One color is surrounded by a very narrow rim of another. (Compare with bordered.) [modified from RDMB, p. 150]
143 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. [modified from K&P, p. 42]
144 Ellipsoid-cylindric[Buds] {shape}; [Seed cones] {shape before opening, shape when open} Intermediate in shape between ellipsoid and cylindric.
145 Elliptic[Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Widest near the middle, with convex sides tapering equally toward both ends [modified from W&K, p. 36]; in the shape of an ellipse or narrow oval [modified from H&H, p. 150]. (Compare with oblong and oval.)
146 Emarginate[Leaf apices, Leaflet apices, Petal apices, Phyllary apices, Sepal apices] {shape} With a notch at the apex. [H&H, p. 153]
147 Ensiform[Leaflets, Leaves] {shape} Long and moderately slender, flat in cross section, gradually tapering to a pointed apex; sword-shaped; as an Iris leaf. (Compare with awl-shaped, linear and lorate.) [modified from K&P, p. 43 & H&H, p. 150]
148 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. [modified from H&H, p. 157]
149 EpidermisThe outermost layer of cells of leaves, young stems and roots. [modified from REE, p. 896]
150 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. (Compare with hypogynous and perigyneous.) [modified from K&P, p. 43]
151 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. (Compare with parasitic.) [modified from K&P, p. 44]
152 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. [modified from Z p. 367]
153 Erose[Leaf margins, Leaflet margins, Petal margins, Phyllary margins, Sepal margins] {form} With the margin irregularly toothed, as if gnawed. [H&H, p. 157]
154 Even-pinnate[Terminal leaflet] {presence} Pinnately compound with an even number of leaflets, none truly terminal. (Compare with odd-pinnate.) [modified from K&P, p. 44]
155 Evergreen[Leaves] {duration} Bearing green leaves through the winter and into the next growing season; persisting two or more growing seasons; not deciduous. (Compare with deciduous and semi-evergreen.) [modified from RDMB, pp. 146 & 154]
156 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) and river birch (Betula nigra). [modified from K&P p. 44]
157 Falcate[Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Long, arcing to one side and tapering toward the apex; sickle-shaped. [modified from K&P, p. 45]
158 Fan-shaped[Leaflets, Leaves] {shape} Shaped like a fan, as a Gingko leaf.
159 Fascicle[Inflorescences] {type} A tight cluster of stalked (pedicellate) flowers, the stalks originating very close to one another and diverging little if at all. [modified from K&P, p. 45]
160 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). (Compare with clustered and solitary.) [modified from RDMB, p. 119]
161 Fibrous[Roots] {type} With several to many relatively slender roots of about the same diameter. (Compare with tap root.) [modified from W&K, p. 593]
162 FilamentThe stalk of a stamen, which supports an anther at its tip. [modified from K&P, p. 46]
163 Filiform[Leaflets, Leaves] {shape} Long and very slender, basically round in cross section and of uniform diameter; thread-like. (Compare with acicular and linear.) [modified from K&P, p. 46]
164 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). [modified from H p. 18 (see scaly)]
165 Fleshy[Seed cone scales] {type} Fairly firm and dense, juicy or at least moist, and easily cut. (Compare with leathery and woody.) [modified from K&P, p. 47]
166 FloralUpon, within, or associated with the flowers. [K&P, p. 48]
167 Floral cupA 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 cup-shaped, flask-like or tubular; a hypanthium. [modified from REE, p. 897 (see floral tube), Z p. 368, K&P, p. 48, & W&K, p. 595 (see hypanthium)]
168 FloretA very small, structurally specialized flower, especially those of the grasses (Poaceae) and the sunflower family (Asteraceae). [modified from K&P, 48]
169 FlowerThe reproductive structure in flowering plants (angiosperms), consisting of stamens and/or pistils, and usually including a perianth of sepals and/or petals. [modified from H&H, p. 48]
170 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). [modified from K&P, p. 49 & Z p. 368]
171 Four-angled[Leaf cross section] {shape} More or less diamond-shaped in cross section.
172 Four-ranked[Leaves] {habit} With leaves arranged in along the stem in four rows. (Compare with distichous and three-ranked.)
173 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). (Compare with axile placentation.) [Z p. 368]
174 Fringed[Petal apices] {shape}
175 FruitThe 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. [modified from K&P, p. 49]
176 Furrowed[Bark of mature trunks] {surface appearance} Bark with relatively long narrow depressions or grooves, as in tulip-tree (Liriodendron tulipifera). [modified from K&P, p. 50]
177 Fusiform[Buds] {shape} Elongate, broadest at the middle, evenly tapering to either end, and rounded in cross section; spindle-shaped. [modified from K&P, p. 51]
178 FusionThe physical connection of equivalent or dissimilar structures, as fused sepals or petals. [modified from K&P, p. 51]
179 GeminateIn pairs, as a leaf which is divided into two leaflets. (Compare with ternate.)
180 GerminationThe beginning or resumption of growth by a seed, bud or other structure. [modified from REE, p. 898]
181 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 [H&H, p. 167]; pubescent when young, but losing the hairs in maturity [W&K, p. 594].
182 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). (Compare with pubescent.) [modified from W&K, p. 39]
183 Glandular (1)[Petioles, Rachises] {special surface features} Bearing secreting organs, or glands. [modified from L, p. 754]
184 Glandular (2)[Stipules] {type} In the form of a secreting organ or gland. (Compare with blade-like, scale-like and spinose.) [modified from L, p. 754]
185 Glaucous[Buds, Young twigs, Leaves] Covered with a whitish or bluish waxy coating (bloom) that can sometimes be rubbed off. [modified from W&K, p. 594]
186 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. [modified from K&P, p. 52]
187 Glomerule[Inflorescences] {type} A dense cluster of flowers. [modified from H&H, p. 51]
188 GlossyLustrous or shiny, as the upper surface of southern magnolia (Magnolia grandiflora) leaves.
189 GlutinousGluey, sticky or gummy; covered with sticky exudates. [modified from H&H, p. 168]
190 Grass-like herbaceous[Plants] {habit} Herbaceous with relatively long, narrow leaves appearing similar to those of grasses (Poaceae). (Compare with broadleaf herbaceous.)
191 Grooved[Apophyses] {texture} With a narrow depression or groove.
192 Gymnosperm[Plants] {major group} A seed plant which produces seeds that are not enclosed inside an ovary, as the conifers. (Compare with angiosperm.) [modified from REE, p. 898]
193 HabitThe general appearance, characteristic form, or mode of growth of a plant. [H&H, p. 52]
194 Half-inferior[Ovaries] {position} With the lower portion of the ovary enclosed by and fused to a floral cup, the whorl of sepals and petals (perianth) and/or stamens (androecium) thus appearing to arise from near the middle of the ovary. (Compare with inferior and superior.) [modified from K&P, p. 54]
195 Hastate[Leaf bases, Leaflet bases, Leaflets, Leaves] {shape} Arrowhead-shaped, but with the basal lobes turned outward rather than downward. (Compare with sagittate.) [modified from H&H, p. 53]
196 Head[Inflorescences] {type} An inflorescence with crowded, sessile or nearly sessile, small flowers (florets) borne on a common receptacle which is convex or flat and often disc-shaped; characteristic of the sunflower family (Asteraceae). [modified from K&P, p. 55]
197 Helicoid cyme[Inflorescences] {type} A cyme in which the lateral branches develop on only one side, all segments branching on the same side, causing the inflorescence to curve or coil. (Compare with cyme and scorpioid cyme.) [modified from K&P, p. 36]
198 Hemi-parasitic[Plants] {nutrition} Partially parasitic; in plants, photosynthetic but deriving at least some nutrients from a host organism. (Compare with parasitic.) [modified from RDMB, p. 312]
199 Herbaceous[Plants] {woodiness} Having little or no living portion of the shoot persisting aboveground from one growing season to the next, the aboveground portion being composed of relatively soft, non-woody tissue. (Compare with woody.) [modified from K&P, p. 56]
200 Hesperidium[Fruits] {type} A specialized berry with a leathery skin or rind, and a fleshy interior divided into sections or locules, as lemons and oranges (Citrus). (Compare with pepo.) [modified from K&P, p. 56]
201 Hip[Fruits] {type} An aggregation of achenes surrounded by an urn-shaped, more or less fleshy floral cup or hypanthium, as in roses (Rosa). [modified from RDMB, P. 111]
202 Hirsute[Buds, Leaf lower surface, Leaf upper surface, Petioles, Phyllaries, Rachises, Sepals, Young twigs] {pubescence type} With coarse, stiff hairs. [modified from W&K, p. 595]
203 Hispid[Buds, Leaf lower surface, Leaf upper surface, Phyllaries, Sepals, Young twigs] {pubescence type} With stiff, bristly, usually stout-based hairs. [modified from W&K, p. 595]
204 Hollow[Pith] {type} With an uninterrupted central cavity, the pith lacking or disintegrating prior to maturity. (Compare with chambered, continuous and diapraghmed.) [modified from K&P, p. 57]
205 HypanthiumA 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 cup-shaped, flask-like or tubular; a floral cup. [modified from REE, p. (see floral tube), Z p. 368 (see floral cup), K&P, p. 58, & W&K, p. 595]
206 Hypogynous[Flowers] {perianth position} With the perianth (the whorl of sepals and petals) not fused into a floral cup of any kind and arising at the same level as the base of the ovary. (Compare with epigynous and perigyneous.) [modified from K&P, p. 58]
207 Imbricate (1)[Leaves] {habit} Overlapping, as the shingles on a roof. [modified from L, p. 756]
208 Imbricate (2)[Bud scales] {type} Overlapping, as the shingles on a roof. (Compare with valvate.) [modified from L, p. 756]
209 Impressed[Leaf upper surface venation] {relief}
210 Incised[Leaf margins, Leaflet margins, Petal margins, Phyllary margins, Sepal margins] {form} Margins sharply and deeply cut, usually jaggedly. [RDMB, p. 137]
211 Inconspicuous[Stipule scars] {presence} Not readily visible.
212 IndehiscentNot splitting or forming an opening at maturity, the contents being released for dispersal only after decay, digestion or erosion of the structure, as certain fruits, such as achenes and berries, that retain their seeds when ripe. (Compare with dehiscent.) [modified from K&P, p. 59]
213 Indeterminate inflorescenceAn inflorescence in which the lowermost or outermost flower opens first, with the main axis often elongating as the flowers develop, as in racemes. (Compare with determinate inflorescence.) [modified from Z p. 371]
214 Inferior[Ovaries] {position} With the ovary wholly enclosed by and fused to a floral cup, the whorl of sepals and petals (perianth) and/or stamens (androecium) thus appearing to arise from the top of the ovary. (Compare with half-inferior and superior.) [modified from K&P, p. 60]
215 Inflorescence1) The mode or pattern of flower bearing; the arrangement of flowers on the floral axis. 2) A basic unit of the flower-producing portion of a plant, composed of one or more flowers and any supporting stalks and appendages (e.g. bracts, involucres, etc.); a flower cluster. [modified from K&P, p. 60]
216 Infrapetiolar[Buds] {position} Axillary and surrounded by the base of the leaf stalk or petiole. [modified from K&P, p. 60]
217 InsertionThe location of points of attachment of a structure (e.g., a leaf) to some dissimilar bearing structure (e.g., a twig). [modified from K&P, p. 60]
218 InternodeThe portion of a stem between two nodes, i.e. the part where leaves and/or branches do not arise. [H&H, p. 60]
219 InvolucreA whorl of bracts subtending a flower or flower cluster. [H&H, p. 61]
220 Involute[Leaf margins, Leaflet margins] {vertical disposition} With margins rolled inward, toward the upper side. (Compare with plane and revolute.) [modified from H&H, p. 157]
221 KeelA longitudinal ridge, more or less triangular in cross section, like the keel of a boat. [modified from K&P, p. 61]
222 Keeled (1)[Petals] {shape}
223 Keeled (2)[Apophyses] {keels} With a vertical ridge or keel. (Compare with cross-keeled.)
224 Keeled above[Leaves] {keels} With a longitudinal ridge or keel, more or less triangular in cross section, running down the center of the upper surface of the leaf. (Compare with keeled below.) [modified from K&P, p. 61]
225 Keeled below[Leaves] {keels} With a longitudinal ridge or keel, more or less triangular in cross section, running down the center of the lower surface of the leaf. (Compare with keeled above.) [modified from K&P, p. 61]
226 Lacerate[Leaf margins, Leaflet margins, Petal margins, Phyllary margins, Sepal margins] {form} Margins irregularly cut, appearing torn. [RDMB, p. 137]
227 Laciniate[Leaf margins, Leaflet margins, Petal margins, Phyllary margins, Sepal margins] {form} Cut into narrow, ribbon-like segments. [modified from H&H, p. 157]
228 Lance-cylindric[Buds] {shape}; [Seed cones] {shape before opening, shape when open} Intermediate in shape between lanceoloid and cylindric.
229 Lance-obovoid[Seed cones] {shape before opening, shape when open} Intermediate in shape between lanceoloid and obovoid.
230 Lance-ovoid[Buds] {shape}; [Seed cones] {shape before opening, shape when open} Intermediate in shape between lanceoloid and ovoid.
231 Lanceolate[Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Several times longer than broad, widest near the base and tapering to a point at the apex; lance-head-shaped. (Compare with oblanceolate.) [modified from W&K, p. 36]
232 Lanceoloid[Buds] {shape}; [Seed cones] {shape before opening, shape when open} Considerably longer than broad, rounded or somewhat flattened in cross section, broadest near the base and somewhat concavely tapering toward the tip; lance-head shaped in outline. [modified from K&P, p. 63]
233 LeafA lateral outgrowth of a stem, usually green and photosynthetic, and often consisting of a stalk (petiole) and an expanded portion (blade); leaves may also be needle-like or scale-like in form. (Compare with leaflet.) [modified from H&K, p. 24]
234 Leaf complexityThe division (or not) of a leaf into distinctly separate segments or leaflets; whether a leaf is simple or compound.
235 Leaf insertionThe position of leaves as defined by the relative location of their points of attachment on the stem (e.g. alternate, opposite, whorled, etc.)
236 Leaf scarThe scar remaining on a twig at the former place of attachment of a leaf, after the leaf has fallen. [modified from H&H, p. 63]
237 Leaf venationThe visible pattern of veins on a leaf. [modified from W&K, p. 608]
238 LeafletOne of the separate, leaf-like segments of a compound leaf. [modified from K&P, p. 64]
239 Leathery[Seed cone scales] {type} Moderately thick, tough and pliable. (Compare with fleshy and woody.) [modified from K&P, p. 64]
240 Legume[Fruits] {type} A usually dry fruit that splits open (dehisces) lengthwise along two sutures and has a single interior chamber (locule), as in the pea family (Fabaceae). (Compare with loment.) [modified from Z p. 373 & K&P, p. 64]
241 LenticelThe specialized openings in the bark of some woody stems that provide a passage for gas exchange, often appearing as small, circular to elongate marks on the surface of the bark. [modified from W&K, p. 596]
242 LepidoteCovered with small scales. [modified from RDMB, p. 141]
243 Linear[Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Long and narrow, with the sides more or less straight and parallel. (Compare with acicular, ensiform, filiform and lorate.) [modified from K&P, p. 66]
244 LobeA more or less major protrusion or segment of a leaf or leaflet delimited by concavities (sinuses) in the leaf margin. [modified from K&P, p. 66]
245 LoculeA distinct compartment or cavity within organs such as ovaries, anthers or fruits. [modified from K&P, pp. 66-67]
246 Loculicidal capsule[Fruits] {type} A capsule that splits open (dehisces) lengthwise directly into the locules or chambers of the ovary, more or less midway between the ovary partitions. (Compare with septicidal capsule.) [modified from Z p. 374 & L p. 760]
247 Loment[Fruits] {type} A usually dry fruit that breaks apart crosswise at points of constriction into one-seeded segments, as in beggar’s ticks (Desmodium); considered to be a modified legume. (Compare with legume.) [modified from Z p. 374 & W&K, p. 597]
248 Lorate[Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Long and moderately narrow, flat in cross section, with sides more or less straight and parallel, often flexible and curving; strap-shaped. (Compare with ensiform and linear.) [modified from K&P, p. 67]
249 Lyrate[Leaflets, Leaves] {shape} Pinnately lobed, with a large, rounded terminal lobe and smaller lower lobes; lyre-shaped. (Compare with pandurate, runcinate and spatulate.) [modified from H&H, p.150]
250 Marbled[Leaf lower surface, Leaf upper surface] {color variegation} A surface traversed by irregular veins of color, as a block of marble. [modified from RDMB, p. 150]
251 MarginThe edge, as in the edge of a leaf blade. [H&H, p. 67]
252 Marginal[Placentation] {type} Attachment of ovules along one side of a simple ovary. (Compare with parietal placentation.) [modified from H&K, p. 25]
253 Mericarp[Fruits] {type} One of the segments of a schizocarp once it has split apart, often appearing to be a separate fruit; usually one-seeded and not splitting open at maturity (indehiscent); as the small, relatively hard-coated “nutlets” in the mint familiy (Lamiaceae) or the individual winged samaras of maples (Acer). [modified from K&P, p. 69]
254 MidribA main or primary vein running lengthwise down the center of a leaf or leaf-like structure; a continuation of the leaf stalk (petiole); the midvein. [modified from W&K, p. 598, & K&P, p. 70]
255 MidveinA main or primary vein running lengthwise down the center of a leaf or leaf-like structure; a continuation of the leaf stalk (petiole); the midrib. [modified from W&K, p. 598 (see midrib), & K&P, p. 70]
256 Moderately lobed[Leaflets, Leaves, Petals, Sepals] {lobing} With lobes that are cut approximately 1/4 to 1/2 the distance to the midrib or base. (Compare with deeply lobed, divided and shallowly lobed.) [modified from RDMB, p. 137 (see cleft) & H&H, pp. 157 (see cleft)]
257 Monoecious[Plants] {distribution of gender} Having functionally unisexual (i.e. separate male and female) flowers or cones, which are borne on the same plant; each plant thus possessing both male and female reproductive structures. (Compare with dioecious and synoecious.) [modified from K&P, p. 70]
258 Mucronate[Leaf apices, Leaflet apices, Petal apices, Phyllary apices, Sepal apices] {shape} Ending abruptly in a short, hard point. (Compare with apiculate, aristate and caudate.) [modified from K&P, p.71]
259 MultilocularWith more than one interior compartment or locule. (Compare with unilocular.)
260 Multiple fruit[Fruits] {type} A fruit formed from several flowers (and associated parts) more or less coalesced into a single structure with a common axis, as a mulberry (Morus) or pineapple (Ananas comosus). (Compare with aggregate fruit.) [modified from Z p. 375 & H&H, p. 71]
261 Naked[Bud scales] {type} With no scales covering the immature shoot.
262 Nearly sessile[Flowers, Leaflets, Leaves, Seed cones] {form of attachment} With a very short, somewhat indistinct stalk. (Compare with petiolate, petioulate, sessile and stalked.) [modified from K&P, p. 106]
263 Nearly symmetric[Seed cones] {symmetry} Not fully symmetric, but divisible into nearly equal halves along one or more planes. (Compare with asymmetric and symmetric.)
264 NectarA sugary, sticky fluid secreted by many plants. [H&H, p. 73]
265 Nectary-bearing[Petioles, Rachises] {special surface features} Bearing a glandular structure that secretes nectar [modified from W&K, p. 598 (see nectary)], often appearing as a protuberance, scale or pit [modified from L, p. 762 (see nectary)].
266 Needle-like[Leaves] {general form} With leaves that are more or less needle-shaped, and usually evergreen; they may be flattened as in hemlocks (Tsuga) or more rounded as in pines (Pinus). (Compare with broad-leaved and scale-like.)
267 NodeThe portion of a stem where leaves and/or branches arise; often recognizable by the presence of one or more buds. (Compare with internode.) [modified from H&H, p. 73]
268 Not persistent[Seed cones] {persistence} Falling from the branch soon after shedding seeds.
269 Not serotinous[Seed cones] {serotiny} Having cones that open when the seeds ripen or soon thereafter.
270 Nut[Fruits] {type} A more or less large, dry fruit that does not split open at maturity (indehiscent), with a single inner chamber and a thick, bony wall surrounding a single seed, as walnuts (Juglans). [modified from Z p. 376 & K&P, p. 73]
271 NutritionMode of acquiring substances necessary for growth and development. [modified from K&P, p. 73]
272 Obcordate[Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Heart-shaped with the point of attachment at the narrow end; inversely cordate. (Compare with cordate and obdeltoid.) [modified from H&H, p.150]
273 Obdeltoid[Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Similar in shape to an equilateral triangle, with the point of attachment at the narrow end; inversely deltoid. (Compare with deltoid and obcordate.) [modified from H&H, p.150]
274 Oblanceolate[Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Several times longer than broad, widest near the apex and tapering to a point at the place of attachment; inversely lanceolate. (Compare with lanceolate and spatulate.) [modified from H&H, p.150]
275 Oblique[Leaf bases, Leaflet bases] {shape} Having an asymmetrical base. [RDMB, p. 137]
276 Oblong (1)[Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Shaped like a compressed oval, with the sides approximately parallel for most of their length. (Compare with elliptic.) [modified from K&P, p. 73]
277 Oblong (2)[Buds] {shape}; [Seed cones] {shape before opening, shape when open} Shaped like an elongated ellipsoid, the sides almost parallel from near one end to near the other end. [modified from K&P, p. 73]
278 Oblong-cylindric[Buds] {shape} Intermediate in shape between oblong and cylindric.
279 Oblong-cylindric[Seed cones] {shape before opening, shape when open} Intermediate in shape between oblong and cylindric.
280 Oblong-ovoid[Buds] {shape}; [Seed cones] {shape before opening, shape when open} Intermediate in shape between oblong and ovoid.
281 Obovate[Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Egg-shaped with the point of attachment at the narrower end; inversely ovate. (Compare with ovate.) [modified from H&H, p.150]
282 Obovoid[Seed cones] {shape before opening, shape when open} Egg-shaped with the base at the narrow end; inversely ovoid. [modified from K&P, p. 74]
283 Obtuse (1)[Leaf apices, Leaflet apices, Petal apices, Phyllary apices, Sepal apices] {shape} More or less blunt at the apex, with the sides coming together at an angle of greater than 90º. (Compare with acute.) [modified from H&H, p. 153]
284 Obtuse (2)[Leaf bases, Leaflet bases] {shape} More or less blunt at the base, with the sides coming together at an angle of greater than 90º. [modified from W&K, p. 37]
285 Ocellated[Leaf lower surface, Leaf upper surface] {color variegation} A broad spot of some color has another spot of a different color within it. (Compare with zoned.) [modified from RDMB, p. 150]
286 Odd-pinnate[Terminal leaflet] {presence} Pinnately compound with an odd number of leaflets, one of them terminal. (Compare with even-pinnate.) [modified from K&P, p. 74]
287 Once palmately compound[Leaves] {complexity form} Compound with leaflets all attached at a common point and diverging from one another. (Compare with once pinnately compound, bipalmately compound and tripalmately compound.) [modified from K&P, p. 76]
288 Once pinnate-pinnatifid[Leaves] {complexity form} Once pinnately compound with pinnatifid leaflets. (Compare with bipinnate-pinnatifid and tripinnate-pinnatifid.)
289 Once pinnately compound[Leaves] {complexity form} Compound with leaflets attached at different points along and on either side of a central axis or rachis. (Compare with once palmately compound, bipinnately compound and tripinnately compound.) [modified from K&P, p. 81]
290 Once pinnately lobed[Leaves] {lobing form} With several main segments or lobes positioned along and on either side of a central axis; lobed in a feather-like pattern. (Compare with palmately lobed.) [modified from K&P, p. 81 (see pinnate)]
291 Opposite[Leaves] {insertion} Positioned in pairs along the stem, the members of each pair at the same level across from one another; two leaves occurring at each node. (Compare with alternate and whorled.) [modified from K&P, p. 75]
292 Orbiculate[Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Approximately circular in outline. (Compare with oval and reniform.) [modified from H&H, p.150]
293 Oval (1)[Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Broadly elliptic, the width more than one-half the length, with rounded ends. (Compare with elliptic, orbiculate and ovate.) [modified from H&H, p.150]
294 Oval (2)[Leaf cross section] {shape} Elliptic in cross section.
295 Ovary[Flowers] The lower portion of a pistil where ovules are borne; often distinguishable from the rest of the pistil by its larger circumference. [modified from K&P, p. 75]
296 Ovate[Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Egg-shaped in outline, with the broader end near the base. (Compare with obovate and oval.) [modified from H&H, p.150]
297 Ovoid[Buds] {shape}; [Seed cones] {shape before opening, shape when open} Rounded in cross section, broadest near a bluntly rounded base and convexly tapering to a narrower rounded tip; egg-shaped. [modified from K&P, p. 75]
298 Ovoid-acuminate[Buds] {shape} Egg-shaped but with the narrow end concavely tapering to a point.
299 Ovoid-conic[Buds] {shape}; [Seed cones] {shape before opening, shape when open} Intermediate in shape between ovoid and conic.
300 Ovoid-cylindric[Buds] {shape}; [Seed cones] {shape before opening, shape when open} Intermediate in shape between ovoid and cylindric.
301 Ovoid-ellipsoid[Buds] {shape} Intermediate in shape between ovoid and ellipsoid.
302 OvuleThe structure in flowering plants and gymnosperms which when fertilized develops into a seed. [modified from H&K, p. 29]
303 Painted[Leaf lower surface, Leaf upper surface] {color variegation} Colors disposed in streaks of unequal intensity. [RDMB, p. 150]
304 Palmate (1)With three or more leaflets, lobes or other structures arising from a common point and diverging from one another; arranged or structured in a hand-like pattern. (Compare with pinnate.) [modified from K&P, p. 76 & RDMB, p. 139]
305 Palmate (2)[Leaf venation, Leaflet venation] {form} With three or more primary veins arising from a common point at or near the base of the leaf or leaflet blade. (Compare with dichotomous, parallel, pinnate and reticulate venation.) [modified from RDMB, p. 139]
306 Palmately lobed[Leaflet, Leaves] {lobing form} With three or more main segments or lobes essentially arising from a common point near the base of the leaf or leaflet blade; lobed in a hand-like pattern. (Compare with once pinnately lobed.) [modified from RDMB, p. 139]
307 Pandurate[Leaflets, Leaves] {shape} Basically inversely egg-shaped (obovate), but with two opposite rounded sinuses in the lower half and two small basal lobes; fiddle-shaped. (Compare with lyrate.) [modified from K&P, p. 76]
308 Panicle[Inflorescences] {type} A branched raceme, the main axis either determinate or indeterminate, and the lateral branches racemose; more loosely, a much-branched inflorescence of various types. (Compare with raceme and thyrse.) [modified from K&P, p. 76]
309 PappusA ring or pair of hairs, bristles, awns or scales attached at the top of the ovary just beneath the petals, persisting in fruit and often aiding in dispersal by wind or animals, especially in the sunflower family (Asteraceae). [modified from K&P, p. 77 & Z p. 377]
310 Parallel[Leaf venation, Leaflet venation] {form} With two or more primary veins that run more or less parallel from the base to the tip of the leaf or leaflet blade. (Compare with dichotomous, palmate, pinnate and reticulate venation.) [modified from K&P, p. 87 (see parallelodromous)]
311 Parasitic[Plants] {nutrition} Living in or on an organism of a different species and deriving nutrients from it. (Compare with autotrophic, epiphytic, hemi-parasitic and saprophytic.) [modified from REE, p. 904]
312 Parietal[Placentation] {type} Attachment of ovules on the inner wall, or intrusions of the wall, of a compound ovary with a single inner compartment (unilocular). (Compare with marginal placentation.) [modified from RDMB, p. 18]
313 Pectinate[Leaves] {habit} Arranged like the teeth of a comb, the leaves slender and more or less perpendicular to the stem; comb-like. [modified from K&P, p. 78]
314 PedicelThe stalk of a individual flower, either that of a solitary flower or of single flowers in a multi-flower inflorescence. (Compare with peduncle.) [modified from K&P, p. 78]
315 PeduncleThe main stalk of a multi-flower inflorescence or of a cluster of flowers within an inflorescence. (Compare with pedicel.) [modified from K&P, p. 79]
316 Peltate[Leaf bases, Leaflet bases] {shape} Having the leaf stalk (petiole) attached to the lower surface of the leaf, usually near the center. [modified from RDMB, p. 137]
317 Pepo[Fruits] {type} A specialized berry with a hard or leathery rind and a fleshy interior surrounding a mass of seeds, without interior sections or locules, as melons and cucumbers (Cucumis). (Compare with hesperidium.) [modified from Z p. 378]
318 Perennial[Plants] {life span} Normally living more than two years, with no definite limit to its life span. [K&P, p. 79]
319 Perfoliate[Leaf bases, Leaflet bases] {shape} Having the base completely surrounding the stem, so that the stem appears to pass through the leaf. [modified from H&H, p. 150]
320 PerianthThe collective term for the outer sterile parts of a flower, comprising the calyx (sepals) and the corolla (petals) when both whorls are present. [modified from W&K, p. 600]
321 Perigynous[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 either a) fused to and partially encloses the ovary (the perianth thus appearing to arise at a level between the bottom and top of the ovary), or b) free from the ovary and extending up and around it to some extent. (Compare with epigynous and hypogynous.) [modified from K&P, p. 79-80]
322 Persistent (1)[Petals, Sepals, Stipules] {persistence} Remaining attached; not falling off early, as stipules that remain attached while the leaves are attached. (Compare with caducous.) [modified from L, p. 764]
323 Persistent (2)[Seed cones] {persistence} Remaining on the branch long after shedding seeds, sometimes for many years.
324 Persistent (3)[Seed cone armature] {persistence} Remaining attached; not falling off while the cone is still intact. (Compare with deciduous.) [modified from L, p. 764]
325 PetalA unit or segment of the inner floral envelope or corolla of a flower; often colored and more or less showy. (Compare with sepal.) [modified from L, p. 764]
326 Petiolate[Leaves] {form of attachment} With a leaf stalk or petiole. (Compare with nearly sessile, petiolulate and sessile.)
327 PetioleThe stalk of a leaf. (Compare with petiolule and rachis.) [modified from W&K, p. 600]
328 Petiolulate[Leaflets] {form of attachment} With a leaflet stalk or petiolule. (Compare with nearly sessile, petiolate and sessile.)
329 PetioluleThe stalk of a leaflet of a compound leaf. (Compare with petiole.) [modified from H&H, p. 84]
330 PhotosyntheticAble to convert light energy to chemical energy by means of chlorophylls and other photosynthetic pigments. [modified from REE, p. 905 (see photosynthesis)]
331 Pilose[Buds, Leaf lower surface, Leaf upper surface, Petioles, Phyllaries, Rachises, Sepals, Young twigs] {pubescence type} With soft, more or less straight hairs. [modified from W&K, p. 39]
332 Pinnate (1)With several leaflets, lobes or other structures positioned along and on either side of a central axis; arranged or structured in a feather-like pattern. (Compare with palmate.) [modified from K&P, p. 81]
333 Pinnate (2)[Leaf venation, Leaflet venation] {form} With secondary veins arising from a single, large midvein. (Compare with dichotomous, palmate, parallel and reticulate venation.) [modified from RDMB, p. 139]
334 Pinnately lobed[Leaflets] {lobing form} With several main segments or lobes positioned along and on either side of a central axis; lobed in a feather-like pattern. (Compare with palmately lobed.) [modified from K&P, p. 81 (see pinnate)]
335 PinnatifidWith several lobes positioned along and on either side of a central axis; lobed in a feather-like pattern. [modified from K&P, p. 81]
336 PistilThe female or ovule-bearing organ of a flower, typically composed of an ovary, style and stigma. [modified from Z p. 379]
337 Pistillate[Flowers] {gender} Having functional pistils, but no functional stamens, making the flower unisexual and female. (Compare with staminate.) [modified from K&P, p. 81]
338 PithThe more or less soft and spongy tissue in the center of some stems and roots; sometimes degenerating to leave a hollow tube. [modified from H&H, p. 87]
339 PlacentationThe arrangement of ovules within the ovary. [modified from L, p. 765]
340 Plane[Leaf margins, Leaflet margins] {vertical disposition} With midrib and margin all in one plane, or nearly so; flat. (Compare with involute and revolute.) [modified from W&K, p. 39]
341 Plated[Bark of mature trunks] {surface appearance} Bark with relatively large, more or less flat plates, as in mature loblolly pine (Pinus taeda) or mature white oak (Quercus alba). (Compare with checkered.)
342 PollenThe small, often powdery, grains which contain the male reproductive cells of flowering plants and gymnosperms. [modified from H&K, p. 33]
343 Pollen coneA male or pollen-producing cone; typically smaller and of shorter duration than seed cones.
344 Polygamous[Plants] {distribution of gender} Having both bisexual (combined male and female) and unisexual (separate male and female) flowers or cones, which are borne on the same plant or on different plants of the same species. [modified from K&P, p. 83]
345 Pome[Fruits] {type} A fleshy fruit that does not split open at maturity (indehiscent), with a more or less soft outer part derived from ripened hypanthium; the interior portion enclosing the seeds is divided into several sections or locules bounded by cartilaginous tissue; as apples (Malus). [modified from K&P, p. 84]
346 Poricidal capsule[Fruits] {type} A capsule that develops openings or pores (dehisces), usually at or near the apex, through which the seeds pass to the outside; as in poppy (Papaver). [modified from K&P, p. 84]
347 PrickleA small, sharp, non-woody structure developed from outgrowth of the surface of bark or epidermis. (Compare with spine and thorn.) [modified from W&K, p. 39]
348 Primary veinA main vein in a leaf or other laminar structure from which other veins branch; the midvein or midrib when present. [modified from K&P, p. 84]
349 Pseudoterminal[Buds] {position} Appearing to be the terminal bud, but actually the uppermost axillary bud with a subtending leaf scar on one side and the scar of the terminal bud often visible on the other side. (Compare with terminal.) [modified from L, p. 767]
350 Puberulent[Buds, Leaf lower surface, Leaf upper surface, Petioles, Phyllaries, Rachises, Sepals, Young twigs] {pubescence type} With very short hairs. [modified from W&K, p. 39]
351 PubescenceThe broad term for any type of plant hairiness. [W&K, p. 602]
352 Pubescent[2-4-year-old twigs, Buds, Leaf lower surface, Leaf upper surface, Petals, Petioles, Phyllaries, Rachises, Sepals, Young twigs] {pubescence} Bearing plant hairs (trichomes). (Compare with glabrous.) [modified from W&K, p. 39]
353 Punctate glandular[Petioles, Rachises] {special surface features} Bearing sessile or embedded glands. (Compare with stipitate glandular.) [modified from W&K, p. 602 (see punctate)]
354 Raceme[Inflorescences] {type} An elongate, indeterminate inflorescence with stalked flowers borne singly along an unbranched main axis or rachis. (Compare with panicle and spike.) [modified from K&P, p. 87]
355 RacemoseIn the form of a simple or compound raceme; bearing racemes. [modified from H&K, p. 35]
356 Rachis1) The main axis of a compound leaf above the point of attachment of the lowermost leaflet; a continuation of the leaf stalk or petiole. 2) The main axis of a compound inflorescence above the point of attachment of the lowermost flower; a continuation of the inflorescence stalk or peduncle. [modified from W&K, p. 33]
357 Radially symmetric[Calyx, Corolla] {symmetry} Divisible into two essentially equal portions along more than one plane. (Compare with asymmetric and bilaterally symmetric.) [modified from K&P, p. 12 (see actinomorphic)]
358 Raised[Leaf upper surface venation] {relief}
359 Receptacle1) The more or less enlarged end of an individual flower stalk (pedicel) which bears some or all of the flower parts. 2) The enlarged end of a compound flower stalk (peduncle) bearing two or more flowers, or the florets of a head, as in the sunflower family (Asteraceae). [modified from W&K, p. 602, Z p. 381 & K&P, p. 88]
360 Reflexed[Leaves, Petals, Sepals] {vertical orientation} Bent backward or downward. (Compare with appressed, ascending and spreading.) [modified from H&H, p. 98]
361 Reniform[Leaflets, Leaves] {shape} Broader than long, broadly rounded and notched at the base; kidney-shaped. (Compare with cordate and orbiculate.) [modified from W&K, p. 603]
362 Reticulate[Leaf venation, Leaflet venation] {form} With a clearly visible network of interconnecting veins. (Compare with dichotomous, palmate, parallel and pinnate venation.) [modified from W&K, p. 603 & K&P, p. 89]
363 Revolute[Leaf margins, Leaflet margins] {vertical disposition} With margins rolled backward, toward the underside. (Compare with involute and plane.) [modified from H&H, p. 158]
364 Rhizome[Stems] {type} An underground, usually horizontal stem, often resembling a root but bearing nodes (points where leaves and/or branches can arise); usually with adventitious roots. (Compare with stolon and tuber.) [modified from K&P, p. 89]
365 Rhombic[Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Broadest at the middle, with more or less straight sides of equal length tapering to either end; diamond-shape. [modified from K&P, p. 89]
366 Ridged[Bark of mature trunks] {surface appearance} Bark with long, narrow protrusions or ridges, as in tulip-tree (Liriodendron tulipifera). [modified from K&P, p. 90]
367 RootThe portions of a plant that are anatomically distinct from the shoot and that lack nodes and internodes; roots serve for anchorage, absorption and/or storage, and usually grow below ground. (Compare with shoot.) [modified from K&P, pp. 87-88 (see radix)]
368 Rosetted[Leaves] {habit} With leaves in a tight cluster radiating from a central axis, usually at or near the base of the stem, as in dandelion (Taraxacum). [modified from W&K, p. 603]
369 Rounded[Leaf apices, Leaf bases, Leaflet apices, Leaflet bases, Petal apices, Phyllary apices, Sepal apices] {shape} Forming a smooth, continuous curve. [W&K, p. 37]
370 RugoseWrinkled. [H&H, p. 170]
371 Runcinate[Leaflets, Leaves] {shape} Broad near the apex and tapering toward the base, with a series of coarse, sharp lobes on either side that mostly point toward the base, as a dandelion (Taraxacum) leaf. (Compare with lyrate.) [modified from K&P, p. 92]
372 Saccate[Petals] {shape}
373 Sagittate[Leaf bases, Leaflet bases, Leaflets, Leaves] {shape} Arrowhead-shaped, with the basal lobes directed downward. (Compare with hastate.) [H&H, p.102]
374 Samara[Fruits] {type} A winged, more or less dry fruit that does not split open at maturity (indehiscent), and contains a single seed, as in ash (Fraxinus) and maple (Acer). [modified from Z p. 382]
375 SapThe fluids circulated throughout a plant. [modified from H&H, p. 102]
376 Saprophytic[Plants] {nutrition} Obtaining nourishment from dead organic matter. (Compare with parasitic.) [modified from RDMB, p. 312]
377 ScabrousRough and sand-papery to the touch, due to structure of the epidermis or to the presence of short stiff hairs. (Compare with smooth.) [modified from W&K, p. 603 & H&H, pp. 170-71]
378 Scale1) Small, flattened structures that are usually thin, dry and membranous in texture. 2) Small, often triangular shaped, leaves that are appressed to the branchlets as in Juniper (Juniperus).
379 Scale-like (1)[Leaves] {general form} With small, typically triangular-shaped leaves that are often appressed to the branchlets, as in juniper (Juniperus). (Compare with broad-leaved and needle-like.) [modified from W&K, p. 603]
380 Scale-like (2)[Petals, Phyllaries, Sepals] {shape} Having the form of small, often triangular shaped, leaves that are appressed to the branchlets, as in juniper (Juniperus). [modified from W&K, p. 603]
381 Scale-like (3)[Stipules] {type} In the form of a small, flattened structure, usually thin, dry and membranous in texture. (Compare with blade-like, glandular and spinose.) [modified from W&K, p. 603]
382 Scaly[2-4-year-old twigs, Petioles, Rachises] {special surface features} Bearing scales of one kind or another.
383 Scarious[Stipules] {type}
384 Schizocarp[Fruits] {type} A dry fruit with two or more interior chambers (locules), splitting open (dehiscing) along the partitions between chambers and separating into indehiscent, usually one-seeded segments (mericarps), as in the carrot family (Apiaceae) and maples (Acer). [modified from K&P, p. 94]
385 Scorpioid cyme[Inflorescences] {type} A cyme in which the lateral branches develop on only one side, each successive segment branching on the side opposite the previous one, producing a more or less zig-zag effect. (Compare with cyme and helicoid cyme.) [modified from K&P, p. 36]
386 ScurfyCovered with small, bran-like scales. [H&H, p. 171]
387 Secondary veinA vein in a leaf or other laminar structure that branches from a main or primary vein; a side vein. [modified from K&P, p. 95]
388 SeedA mature or ripened ovule. [modified from K&P, p. 95]
389 Seed coneA female or ovule-producing cone; typically larger and persisting longer than pollen cones.
390 Semi-evergreen[Leaves] {duration} Bearing green leaves into or through the winter, but dropping them by the beginning of the next growing season; tardily deciduous or winter deciduous. (Compare with deciduous and evergreen.)
391 Semi-persistent[Seed cones] {persistence} With some cones remaining on the branch after shedding seeds.
392 Semicircular[Leaf cross section] {shape} Shaped like a half circle in cross section.
393 SepalA unit or segment of the outermost floral envelope or calyx of a flower; usually green and leaf-like. (Compare with petal.) [modified from L, p. 769]
394 Septicidal capsule[Fruits] {type} A capsule that splits open (dehisces) lengthwise along lines formed by the septa or the partitions separating chambers (locules) inside the ovary. (Compare with loculicidal capsule.) [modified from Z p. 383]
395 Septum (plural septa)A distinct wall or partition that separates the chambers or locules of an ovary, fruit or other structure. [modified from K&P, p. 97]
396 Sericeous[Buds, Leaf lower surface, Leaf upper surface, Phyllaries, Sepals, Young twigs] {pubescence type} With long, silky, usually appressed hairs. [modified from RDMB, p. 140]
397 Serotinous[Seed cones] {serotiny} Having cones that remain closed long after the seeds are ripe. [modified from D, p. 1143]
398 SerotinyThe tendency of some seed cones to remain closed long after the seeds are ripe.
399 Serrate[Leaf margins, Leaflet margins, Petal margins, Phyllary margins, Sepal margins] {form} Toothed along the margin, the sharp teeth pointing forward; sawtoothed. (Compare with crenate, dentate and serrulate.) [modified from H&H, p. 158 & K&P, p. 97]
400 Serrulate[Leaf margins, Leaflet margins] {form} Toothed along the margin with very small, sharp, forward-pointing teeth; finely serrate or small-sawtoothed. (Compare with crenulate, denticulate and serrate.) [modified from H&H, p. 158 & K&P, p. 97]
401 Sessile[Flowers, Leaflets, Leaves, Seed cones] {form of attachment} Without a stalk, positioned directly against the bearing structure. (Compare with petiolate, petioulate, nearly sessile and stalked.) [modified from W&K, p. 604]
402 Shallowly lobed[Leaflets, Leaves, Petals, Sepals] {lobing} With lobes that are cut approximately 1/8 to 1/4 the distance to the midrib or base. (Compare with deeply lobed, divided and moderately lobed.) [modified from RDMB, p. 137 (see lobed) & H&H, pp. 157 (see lobed)]
403 Sheathing[Leaf bases, Leaflet bases] {shape} Having a tubular structure partially or completely enclosing the stem below the apparent point of attachment of the leaf blade or stalk (petiole). [modified from RDMB, p. 137]
404 Shoot1) The portions of a plant that are anatomically distinct from the root and differentiated into nodes, where leaves and branches originate, and the spaces in between (internodes); shoots consist of stems, leaves and any other structures borne from the stem. (Compare with root.) [modified from K&P, p. 98] 2) A young stem or branch. [H&H, p. 107]
405 Short shootA stumpy, slow growing, lateral branch with very short internodes, often bearing flowers; a dwarf shoot. [modified from W&K, p. 604]
406 Shreddy[Bark of mature trunks] {surface appearance} Soft but coarse, fibrous bark, usually shallowly furrowed, as in eastern red cedar (Juniperus virginiana). [RDMB, p. 91]
407 Shrub[Plants] {habit} A relatively short, woody, perennial plant, usually without a single stem or trunk, and often with many crowded branches. (Compare with subshrub and tree.) [modified from RDMB, p. 88]
408 Silicle[Fruits] {type} A dry fruit that splits open (dehisces) along two sutures, the exterior walls eventually falling away in two halves, leaving a single, persistent, interior partition (septum) to which the seeds are attached; usually not more than twice as long as wide; common in the mustard family (Brassicaceae). (Compare with silique.) [modified from K&P, p. 98 & Z p. 384]
409 Silique[Fruits] {type} A dry fruit that splits open (dehisces) along two sutures, the exterior walls eventually falling away in two halves, leaving a single, persistent, interior partition (septum) to which the seeds are attached; usually at least twice as long as wide; common in the mustard family (Brassicaceae). (Compare with silicle.) [modified from K&P, p. 98 & Z p. 384]
410 Simple[Leaves] {complexity} Undivided, as a leaf blade that is not separated into distinct leaflets; not compound. [modified from H&H, p. 156]
411 Simple dichasium[Inflorescences] {type} A determinate, cymose, three-flowered inflorescence composed of a main stalk bearing a terminal flower and a pair of opposite or nearly opposite lateral flowers. (Compare with compound dichasium and cyme.) [modified from K&P, p. 38]
412 Simple ovaryAn ovary composed of only one carpel; recognizable by the presence of only one area of placentation, locule, ovary lobe, style (or style branch), and stigma. (Compare with compound ovary.) [modified from H&H, p. 198]
413 Simple umbel[Inflorescences] {type} An inflorescence composed of several branches that radiate from almost the same point, like the ribs of an umbrella, each terminated by one or more flowers, the upper surface of the whole inflorescence rounded, or more or less flat. (Compare with compound umbel and corymb.) [modified from Z p. 388]
414 Single scale[Bud scales] {type} Covered by a single scale.
415 Sinuate[Leaf margins, Leaflet margins, Petal margins, Phyllary margins, Sepal margins] {form} With the margin smoothly and shallowly indented; wavy in a horizontal plane. (Compare with undulate.) [modified from RDMB, p. 138]
416 SinusThe space or recess between two divisions or lobes of an organ such as a leaf or petal. [modified from L, p. 770]
417 Smooth (1)[Buds, Young twigs, Leaves] With an even surface; not rough to the touch. (Compare with rugose and scabrous.) [H&H, p. 171]
418 Smooth (2)[Bark of mature trunks] {surface appearance} Bark having a more or less continuous, even surface, with relatively few fissures or protrusions, as in American beech (Fagus grandifolia). [modified from H p. xx]
419 Smooth (3)[Apophyses] {texture} With an even surface, lacking keels, grooves or other surface features.
420 Solitary[Inflorescences] {type}; [Needles] {presence of clusters or fascicles} Occurring singly and not borne in a cluster or group. [H&H, p. 175]
421 Spadix[Inflorescences] {type} An inflorescence with small, stalkless (sessile) flowers more or less embedded in a thick, fleshy, unbranched axis or rachis, the whole inflorescence subtended and sometimes partially enclosed by a specialized bract or spathe, as in Jack-in-the-pulpit (Arisaema triphyllum). (Compare with spike.) [modified from K&P, p. 100]
422 SpatheAn often large, sometimes colored and flowerlike bract subtending and sometimes partially enclosing an inflorescence, as in calla lily (Zantedeschia) or jack-in-the-pulpit (Arisaema triphyllum). [modified from K&P, p. 100]
423 Spatulate[Leaflets, Leaves, Petals, Phyllaries, Sepals] {shape} Broad and rounded near the apex with a narrower, long, tapering base; spatula-shaped or spoon-shaped. (Compare with lyrate and oblanceolate.) [modified from K&P, p. 100]
424 Spike[Inflorescences] {type} A usually indeterminate, elongate inflorescence with unstalked (sessile) flowers arranged singly along an unbranched axis or rachis. (Compare with raceme and spadix.) [modified from K&P. p. 100]
425 Spikelet[Inflorescences] {type} The basic unit of inflorescence in the sedges (Cyperaceae) and grasses (Poaceae) consisting of a spike of tiny flowers that lack petals, each subtended by scale-like bracts; spikelets are the ultimate subdivision in a typically more complex inflorescence. [modified from W&K, p. 605]
426 SpineA woody, sharp-pointed, modified leaf or leaf part. (Compare with prickle and thorn.) [modified from W&K, p. 39]
427 Spinose (1)[Leaf apices, Leaflet apices, Petal apices, Phyllary apices, Sepal apices] {shape} Ending in a rigid, tapering, sharp tip; bearing a spine at the apex. [modified from K&P, p. 101]
428 Spinose (2)[Stipules] {type} Modified into a woody, sharp-pointed structure, as a stipular spine. (Compare with blade-like, glandular and scale-like.)
429 Spiny or prickly[Leaf margins, Leaflet margins, Phyllary margins, Sepal margins] {form} Bearing spines or prickles along the margin.
430 Spiny, prickly, thorny[2-4-year-old twigs, Petioles, Rachises] {special surface features} Bearing spines, prickles or thorns.
431 Spiral[Leaves] {insertion} Arranged along the stem in such a way that a line connecting the points of attachment would form a spiral; a form of alternate arrangement. [modified from H&K, p. 39]
432 Spotted[Leaf lower surface, Leaf upper surface] {color variegation} The color disposed in small spots. (Compare with discoidal and dotted.) [modified from RDMB, p. 150]
433 Spreading[Leaves, Petals, Phyllaries, Sepals] {vertical orientation} Extending outward horizontally, or upward at an angle between 90º to 45º relative to the bearing structure. (Compare with appressed, ascending and reflexed.) [modified from K&P, p. 102]
434 Spurred[Petals] {shape}
435 Squarrose[Phyllaries] {vertical orientation}
436 StalkA supporting axis or column that bears a structure at its apex and is usually narrower than the structure being borne, as the stalk of a flower or leaf. [modified from K&P, p. 102]
437 Stalked[Flowers, Seed cones] {form of attachment} With a stalk. (Compare with nearly sessile and sessile.)
438 StamenThe male reproductive organ in a flower that produces and releases pollen, composed of an anther usually borne on a stalk (filament). [modified from Z pp. 384-85]
439 Staminate[Flowers] {gender} Having one or more functional stamens, but no functional pistils, making the flower unisexual and male. (Compare with pistillate.) [modified from K&P, p. 103]
440 Stellate[Buds, Leaf lower surface, Leaf upper surface, Petioles, Phyllaries, Rachises, Sepals, Young twigs] {pubescence type} With hairs that branch from the base and resemble tiny stars. [modified from W&K, p. 605]
441 StemThe axis of a shoot, bearing leaves, bracts and/or flowers, and usually growing above ground, but sometimes specialized and growing underground (see bulb, corm, rhizome and tuber) or on the surface of the ground (see stolon); stems are differentiated into regions called nodes, where leaves and branches originate, and internodes. [modified from K&P, p. 103]
442 Sterigma-bearing[2-4-year-old twigs] {special surface features} With persistent leaf bases that remain on the twig after the leaf falls and appear as peg-like projections.
443 StigmaThe pollen-receptive region at the tip of a pistil. [modified from Z p. 385]
444 Stinging[Leaf lower surface, Leaf upper surface, Petioles, Phyllaries, Rachises, Sepals, Young twigs] {pubescence type} With erect, usually long hairs, that produce irritation when touched, as in stinging nettle (Urtica). [modified from RDMB, p. 140 (see urent)]
445 Stipitate glandular[Buds, Leaf lower surface, Leaf upper surface, Petioles, Phyllaries, Rachises, Sepals, Young twigs] {pubescence type} With stalked glandular hairs. (Compare with punctate glandular.) [modified from W&K, p. 605]
446 StipuleA relatively small, typically leaf-like structure occurring at the base of a leaf stalk (petiole), usually one of a pair; stipules are sometimes in the form of spines, scales or glands. [modified from K&P, p. 104]
447 Stipule scarThe scar remaining on a twig at the former place of attachment of a stipule.
448 Stolon[Stems] {type} A slender horizontal stem, at or just above the surface of the ground, that gives rise to a new plant at its tip or from axillary branches. (Compare with rhizome and tuber.) [modified from W&K, pp. 30-31]
449 Strigose[Buds, Leaf lower surface, Leaf upper surface, Phyllaries, Sepals, Young twigs] {pubescence type} With straight, stiff, sharp appressed hairs. [modified from W&K, p. 605]
450 Striped[Leaf lower surface, Leaf upper surface] {color variegation} Longitudinal, or vertical, stripes of one color crossing another. (Compare with banded.) [modified from RDMB, p. 150]
451 Strong[Seed cone armature] {strength} With sturdy armature that is not easily broken.
452 StyleThe more or less elongated portion of a pistil between the ovary and the stigma. [modified from L, p. 772]
453 Subshrub[Plants] {habit} 1) A shrub-like plant but with only the base composed of woody tissue, the herbaceous branches dying back at the end of each growing season [modified from K&P, pp. 106-107]. 2) A very low shrub that sprawls on the ground; a trailing shrub. (Compare with shrub.) [modified from L, p. 772]
454 Succulent[Plants] {habit} Juicy, fleshy and often thickened, as the stem of a cactus or the leaves of Aloe. [modified from H&H, p. 117]
455 Superior[Ovaries] {position} With the ovary not fused to any portion of a floral cup, the whorl of sepals and petals (perianth) and/or stamens (androecium) thus arising from beneath the ovary. (Compare with inferior and half-inferior.) [modified from K&P, p. 107]
456 Superposed[Buds] {position} Located directly above an axillary bud. (Compare with collateral.) [modified from RDMB, p. 93]
457 Syconium[Fruits] {type} A multiple fruit characteristic of the figs (Ficus) with an enlarged, hollow, flask-like structure that becomes fleshy at maturity and bears numerous tiny, dry fruits along the inner surface. [modified from W&K, p. 606 & Z p. 386]
458 Symmetric[Seed cones] {symmetry} Divisible into essentially equal halves along one or more planes. (Compare with asymmetric and nearly symmetric.) [modified from K&P, p. 108]
459 Sympetalous[Corolla] {fusion} With petals united, at least at the base. (Compare with apopetalous.) [modified from Z p. 386]
460 Synoecious[Plants] {distribution of gender} With all flowers or cones bisexual, i.e. bearing functional reproductive structures of both sexes. (Compare with dioecious and monoecious.) [modified from K&P, p. 109]
461 Synsepalous[Calyx] {fusion} With sepals united, at least at the base. (Compare with aposepalous.) [modified from Z p. 386]
462 Tap[Roots] {type} An enlarged vertical main root that is noticeably larger in diameter than any attached lateral roots. (Compare with fibrous roots.) [modified from W&K, p. 606]
463 Tendril-bearing[2-4-year-old twigs, Petioles, Rachises] {special surface features} With a slender, twining organ used to grasp support for climbing, as grape (Vitis) vines. [modified from H&H, p. 120 (see tendril)]
464 Terminal (1)At the top, tip, or end of a structure. [RDMB, p. 116]
465 Terminal (2)[Inflorescences, Seed cones] {position} At the apex or tip of the stem. (Compare with axillary.) [modified from RDMB, p. 93]
466 Terminal (3)[Buds] {position} At the apex or tip of the stem. (Compare with axillary and pseudoterminal.) [modified from RDMB, p. 93]
467 TernateIn threes, as a leaf which is divided into three leaflets. (Compare with geminate.) [modified from H&H, p. 120]
468 Tessellated[Leaf lower surface, Leaf upper surface] {color variegation} Color arranged in small squares, so as to have some resemblance to a checkered pavement. [RDMB, p. 150]
469 ThornA woody, sharp-pointed, modified stem. (Compare with prickle and spine.) [modified from W&K, p. 39]
470 Three-angled[Leaf cross section] {shape} More or less triangular-shaped in cross section.
471 Three-ranked[Leaves] {habit} With leaves arranged in along the stem in three rows. (Compare with distichous and four-ranked.)
472 Thyrse[Inflorescences] {type} An elongate, many-flowered inflorescence with an indeterminate main axis or rachis and numerous lateral branches, each in the form of a cyme, as in most lilacs (Syringa). (Compare with panicle.) [modified from K&P, p. 111]
473 Tomentose[Buds, Leaf lower surface, Leaf upper surface, Petioles, Phyllaries, Sepals, Young twigs] {pubescence type} With tangled woolly hairs. [modified from W&K, p. 607]
474 Tree[Plants] {habit} A relatively tall, woody, perennial plant usually with a single stem (trunk) that bears branches. (Compare with shrub.) [modified from RDMB, p. 88]
475 TrichomeAny type of plant hair (except for root hairs). [W&K, p. 607]
476 Trifoliolate[Leaves] {complexity form} Compound with three leaflets; three-leafleted or ternate. (Compare with bifoliolate, biternate and triternate.) [modified from W&K, p. 607]
477 Tripalmately compound[Leaves] {complexity form} With three orders of leaflets, each palmately compound; three-times palmately compound. (Compare with once palmately compound and bipalmately compound.) [modified from RDMB, p. 94]
478 Tripinnate-pinnatifid[Leaves] {complexity form} Three times pinnately compound with pinnatifid leaflets. (Compare with bipinnate-pinnatifid and once pinnate-pinnatifid.)
479 Tripinnately compound[Leaves] {complexity form} With three orders of leaflets, each pinnately compound; three-times pinnately compound. (Compare with once pinnately compound and bipinnately compound.) [modified from RDMB, p. 94]
480 Tripinnately lobed[Leaves] {lobing form} With three orders of leaf lobing, each pinnately lobed; three-times pinnately lobed. (Compare with bipinnately lobed and once pinnately lobed.)
481 Triternate[Leaves] {complexity form} With three orders of leaflets, each divided into threes or ternately compound; three-times trifoliolate. (Compare with biternate and trifoliolate.) [modified from RDMB, p. 94]
482 Truncate (1)[Leaf apices, Leaflet apices, Petal apices, Phyllary apices, Sepal apices] {shape} With the apex cut more or less straight across; ending abruptly, almost at right angles to the midrib. [modified from RDMB, p. 134]
483 Truncate (2)[Leaf bases, Leaflet bases] {shape} With the base cut more or less straight across; ending abruptly, almost at right angles to the midrib. [modified from RDMB, p. 134]
484 TrunkThe aboveground, relatively stout, main stem of a tree; the bole. [modified from K&P, p. 133]
485 Tuber[Stems] {type} A solid, enlarged, horizontal, shortened stem, usually borne below ground and containing food reserves, as in potatoes (Solanum tuberosum). (Compare with rhizome and stolon.) [modified from W&K, p. 31]
486 TwigThe relatively small end portion of a woody branchlet; a small branchlet. (Compare with branchlet.) [modified from K&P, p. 114]
487 Two-angled[Leaf cross section] {shape} More or less flat in cross section, with an upper and lower surface.
488 Unarmed[Seed cone scales] {armature} Without a hook, prickle or other sharply pointed structure on the end of the cone scale.
489 Undulate[Leaf margins, Leaflet margins] {vertical disposition}; [Petal margins, Phyllary margins, Sepal margins] {form} With the margin undulating or wavy in a vertical plane. (Compare with sinuate.) [modified from RDMB, p. 138]
490 Unifoliolate[Leaves] {complexity form} A structurally compound leaf with a single leaflet, making it appear simple, the compound nature of the leaf evident by a distinct articulation in the leaf stalk, as in redbud (Cercis canadensis); one-leafleted. [modified from K&P, p. 115]
491 UnilocularWith a single interior compartment or locule. (Compare with multilocular.)
492 Unisexual[Flowers] {gender} Having functional reproductive structures of only one sex in the flower or cone. (Compare with bisexual.) [modified from K&P, p. 115]
493 Unlobed[Leaflets, Leaves, Petals, Sepals] {lobing} With no recesses or indentations in the margin, or with indentations extending less than 1/8 the distance to the midrib or base.
494 Utricle[Fruits] {type} A more or less small, dry fruit that does not split open at maturity (indehiscent), with a thin bladder-like outer wall that is loose and free from the single seed. [Z p. 388]
495 Valvate[Bud scales] {type} With scales (usually two) meeting by the edges without overlapping. (Compare with imbricate.) [modified from L, p. 774]
496 Variably serotinous[Seed cones] {serotiny} Having some cones that open when the seeds ripen and others that remain closed long after the seeds are ripe.
497 Variegated[Leaf lower surface, Leaf upper surface] {color variegation} The color disposed in various irregular, sinuous, spaces. [RDMB, p. 150]
498 Vascular bundleA strand of conducting tissues and associated cells within a stem or connected structure. [modified from K&P, p. 16]
499 Vegetative1) Of, or relating to, the non-flowering parts of a plant. 2) Producing new plants asexually by the spread or fragmentation of sterile (non-reproductive) tissue, without the formation of seeds. [modified from H&K, p. 45 & K&P, p. 116]
500 Verticillaster[Inflorescences] {type} A pair of axillary cymes arising from opposite leaves or bracts and forming a false whorl, as in many salvias (Salvia). [modified from H&H, p. 175]
501 Villous[Buds, Leaf lower surface, Leaf upper surface, Phyllaries, Sepals, Young twigs] {pubescence type} With slender curved or wavy, but not matted hairs. [modified from W&K, p. 39]
502 Vine[Plants] {habit} A perennial plant with long woody or herbaceous stems that are flexible (at least initially), and are supported by other plants or structures, or that trail across the ground. [modified from K&P, p. 118, modified/W&K, p. 608]
503 Warty[Bark of mature trunks] {surface appearance} Bark with relatively small, scattered protuberances, as in southern hackberry (Celtis laevigata). (Compare with checkered.)
504 Weak[Seed cone armature] {strength} With armature that tends to break easily.
505 Whorled[Leaves] {insertion} With three or more leaves positioned on the stem at the same level; three or more leaves occurring at each node. (Compare with alternate and opposite.) [modified from K&P, p. 119]
506 Winged[2-4-year-old twigs, Petioles, Rachises] {special surface features} Having one or more elongate, relatively thin protrusions or appendages that loosely resemble wings, as the twigs of winged elm (Ulmus alata). [modified from K&P, p. 119]
507 Woody (1)[Plants] {woodiness} With an aboveground shoot composed of relatively hard tissue that persists from one growing season to the next. (Compare with herbaceous.)
508 Woody (2)[Seed cone scales] {type} Of or resembling wood, and thus relatively hard and dry. (Compare with fleshy and leathery.) [modified from K&P, p. 119]
509 Wrinkled[Apophyses] {texture} With small folds or creases.
510 Zoned[Leaf lower surface, Leaf upper surface] {color variegation} The same as ocellated, but the concentric bands more numerous. (Compare with ocellated.) [modified from RDMB, p. 150]
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