Glossary

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

A

achene

a fruit which is small, dry, hard, 1-celled and 1-seeded.

accessory bud

a bud in addition to the main axillary bud, may be collateral or superposed.

acorn

the fruit of an oak, not including the cup or peduncle. The nut of an oak.

acuminate

tapering gradually to a point.

acute

ending in a sharp or well-defined point or angle less than 90 degrees.

adventitious bud

a bud produced anywhere on the wood surface, especially where the wood has been injured.

alternate said of leaves which are not opposite each other on the axis but are borne singly at regular intervals at different nodes; of flower parts when they are situated at intervals between other parts, e.g., petals may be alternate with the sepals.

ament

a catkin; a dry scaly pendant spike of unisexual flowers, each subtended by a bract such as the inflorescence of birch or willow, usually deciduous in one piece. A tassel-like group of flowers.

anterior

above, towards the tip or top.

anther

the part of a stamen producing or carrying the pollen.

anthesis

the time in the development of a flower when it is opening.

apex

the tip or summit.

apical

pertaining to or belonging to the tip or point.

appressed

lying close to and pressed against.

arborescent

tree-like.

armed

provided with spines, tubercles or comparable structures.

ascending

rising somewhat obliquely or curving upward.

astringent

harsh, severe, sharp.

asymmetrical

not forming mirror images on opposite sides; lack of symmetry.

attenuate

gradually becoming very narrow or slender.

auriculate

with ear-like appendages; eared.

awn

a bristle-like appendage.

axil

the upper angle formed where a petiole or branch joins a stem; the angle formed between any two organs.

axillary

in or related to an axil, e.g., axillary buds; occurring in an axil.

axillary bud

a bud lying in the angle between the petiole of a simple leaf or the rachis of a compound leaf and the main stem; lateral bud.

axis

the central line of a body; the organ or line around which parts are arranged.

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B

berry

a pulpy indehiscent fruit with one to many seeds; such as the grape, cranberry, blueberry or tomato.

bipinnate twice pinnately compound.

blade

the expanded part of a leaf, petal or sepal.

bloom

a whitish powder which covers a usually waxy surface, but is easily rubbed off, e.g., on prune or plum.

bract

a reduced or modified leaf lying under or opposite to a flower or inflorescence or part thereof, sometimes scale-like.

bracteate

having bracts.

branch

any division or subdivision from the stem except the growth of the current season.

branchlet

the ultimate divisions of a branch. As applied to woody plants, the growth of the season.

bud

an undeveloped or rudimentary stem or branch or flower, with or without scales.

bud scale

modified leaf covering a bud.

bundle-scar

a "dot" or mark on the surface of a leaf-scar, left by the breaking of the vascular bundles which extend through the petiole to the blade of the leaf.

bur

a rough or spiny covering of a fruit.

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C

callous

having the texture of a callus.

callus

a hard protuberance or swelling.

calyx

the outer series of floral leaves forming the perianth of a flower; made up of the sepals, which are green and encircle the flower bud.

calyx limb

the structure formed by the limbs of all the sepals.

capsule

a dry, dehiscent fruit with more than one carpel; it splits at maturity to release the seeds.

carpel

a simple pistil or component of a compound pistil.

catkin an ament.
chambered said of pith which is interrupted by hollow spaces.	Chambered pith	Non-chambered pith

ciliate

with a marginal fringe of hairs.

clone

the dependents of an asexually reproducing individual.

close

in reference to bark means the bark is tight, not peeling or shedding, not scaly.

collateral bud

an accessory bud adjacent to or at the side of the main axillary bud.

colonial

forming colonies; used mainly for plants with underground connections.

compound composed of two or more similar parts united into a whole.

compound corymb

one in which some of the pedicels branch again in the same way that the pedicels of a simple corymb branch.

compound leaf

one divided into separate leaflets, i.e., one in which the blade consists of two or more separate leaflets on a common leaf-stalk or rachis.

compressed

flattened from the side.

conifer a plant commonly having needlelike, persistent leaves and a woody cone for a fruit.

Coniferous branch

cone

a fruit with woody, overlapping scales.

connate

united or grown together.

convolute

rolled up lengthwise.

cordate heart-shaped or "Valentine"-shaped.

coriaceous

leathery in texture.

corolla

the inner series of floral leaves of the perianth of a flower; the petals collectively.

corymb a convex or flat-topped flower cluster in which the outer flowers bloom first and the pedicels become progressively longer toward the base of the rachis.

crenate

the edge scalloped, with rounded teeth.

crenulate

finely crenate.

cuneate wedge-shaped.

cup or cupule

that in which an acorn rests.

cyme a flat or convex flower cluster in which the middle flower blooms first.

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D

deciduous falling away; not persistent; being shed; not evergreen.

Deciduous leaf

decurrent

extending downward from the point of insertion; said of a leaf which extends down the stem (or twig) below the point of fastening or where the blade extends down the petiole.

dehiscent

opening regularly by slits or valves to emit contents.

deliquescent

branching in such a way that the stem is lost in the branches; the main stem branching into numerous smaller ones, e.g., American elm is a deliquescent tree branching without a continuous main stem.

deltoid of a triangular shape, like the Greek capital letter delta (A).

dentate

toothed with the teeth directed outward.

depressed

somewhat flattened from above.

diaphram

a partition between two chambers.

dichotomous

forking or branching regularly by pairs.

dissected

deeply cut or divided into numerous lobes or divisions.

distant

far from each other or from something else.

divaricate

widely divergent.

divergent

inclining away from each other.

doubly serrate

with small serrations on or between larger saw-like teeth.

drupe

a simple fleshy fruit with a fleshy outside portion and a single hard seed, e.g., a stone fruit like a plum or peach.

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E

elliptical wider in the middle and narrowing equally towards the ends; in the shape of an ellipse.

emarginate

cut out or hollowed; notched, especially at the ends.

entire

margin even, smooth; not toothed, notched or divided.

ephemeral

short-lived; lasting for a day or less.

epidermis

the superficial or covering layer of cells.

excurrent

the stem or trunk continuing to the top of a tree; running out, as a vein projecting beyond the margin of a leaf.

exfoliating

peeling off or "shedding" in thin layers.

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F

falcate

scythe-shaped.

fascicle

a compact cluster or bundle.

filament

a thread-like structure; that part of the stamen which supports the anther.

flexuous

zig-zag or curved alternately in opposite directions.

fluted

regularly marked by alternating rounded ridges and groovelike depressions.

fusiform

spindle-shaped, tapering at each end.

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G

glabrescent

becoming glabrous.

glabrous

smooth in the sense of having no hairs; not pubescent.

gland

a secreting surface or structure; usually small cellular organs which secrete oily or other products; sometimes sunk in, sometimes mounted on a stalk or at the tip of a hair or tooth. The name is also used for any protuberance or appendage resembling such a structure.

glaucous

thinly covered with a whitish bloom.

globose

nearly spherical.

glutinous

with a sticky covering.

gymnosperm

a plant producing seeds not enclosed in a seed case or ovary.

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H

hastate

with a spreading lobe on each side at base; halberd-shaped.

head

a dense cluster of sessile or nearly sessile flowers.

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I

imbricate

overlapping like the shingles on a roof; either vertically or spirally where the lower piece covers the base of the next higher, or laterally where at least one piece must be wholly external and one internal.

incised

cut into deeply and irregularly.

indehiscent

not opening by a slit or valves; remaining closed.

inferior

below; beneath.

inflorescence the flowering part of a plant; a flower cluster, an arrangement of flowers on an axis.

insipid

flat, rather tasteless; not tart.

internode

the portion of a stem between two nodes.

involucre

a whorl of bracts surrounding or subtending a flower cluster or head or a single flower.

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K

kernel

a grain or seed as of corn, wheat, etc.; the inner softer part of a nut or fruit stone.

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L

lanceolate shaped like the head of a lance; much longer than wide, tapering to a point at the apex and slightly narrowed at the base.

lateral

situated on the side.

lateral bud

a bud located along the side of a stem, usually in an axillary position, by which the stem branches.

leaflet

one of the divisions or blades of a compound leaf.

leaf sear

the scar left on the stem by the petiole of the leaf after the leaf falls.

legume

a dehiscent, dry fruit of a simple pistil, usually splitting along two sides; like the pod of a pea.

lenticel

a small, lens-shaped, corky area on young bark which admits air to the interior of a twig or branch.

lenticular

lens-shaped; of the shape of a doubly convex lens.

limb

a part towards the edge as opposed to the central part or disc; the expanded portion of a sepal, petal or leaf.

limber

flexible; easily bent.

linear long, narrow and flat with parallel margins; at least 6 times as long as wide.

lobe

any portion of a structure, especially if rounded, which is at least partially set off from the remainder.

lobed divided into or bearing lobes.

Lobed leaf

Not lobed leaf

lunate

the shape of a half-moon or crescent.

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M

medial

of or in the middle.

membranaceous, membranous

having the texture of membrane; a thin, soft, pliable layer which is more or less translucent.

midrib

the central vein or rib of a leaf, usually extending from the base to or near the apex.

moniliform

shaped like a cylindrical body which is constricted at regular intervals; resembling a string of pearls.

mucilaginous

slimy or pertaining to mucilage.

mucronate

abruptly tipped with a short, broad point.

multiple fruit

formed when several flowers are consolidated into one mass with a common axis or receptacle.

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N

node

that part of a stem from which a leaf or a branch starts to grow; a joint in a stem.

nodose

knotty or knobby.

nut

a hard, dry, indehiscent, 1-celled and 1-seeded fruit, usually from a compound ovary, e.g., hazelnut, acorn.

nutlet

a small nut.

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O

obcordate inverted heart-shaped.
oblanceolate inverted lanceolate; lanceolate with the tapering point towards the base.

oblique

slanting or with unequal sides.

oblong longer than wide, with sides nearly parallel
obovate inverted ovate; ovate with the broadest part towards the apex.

obtuse

blunt or rounded.

opposite said of leaves, etc. when they arise on opposite sides of a stem at the same node; of flower parts when they are situated directly above other parts.
orbicular circular.

oval

egg-shaped.

ovary

the basal, usually expanded portion of the pistil containing the ovules.

ovate having the outline of the longitudinal section of an egg with the widest part below the middle.

ovoid

a solid with an ovate outline.

ovule

that which develops into a seed, after fertilization.

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P

palmate

applied to leaves in which the main veins and the sinuses are directed towards the base of the blade where it is attached to the petiole; radially lobed, netted or divided.

palmately compound used to describe a leaf whose leaflets arise from a common point.
panicle a loose, irregularly compound inflorescence with pedicellate flowers; an open, branched, elongated inflorescence, blooming from base upwards.

pedicel

the stalk of a single flower in a compound inflorescence.

pedicellate flower

one with a pedicel.

peduncle

a primary flower stalk, supporting either a single flower or a cluster.

peltate shield-shaped and attached to the support by the lower surface.

pendent

hanging downward. Also spelled pendant.

pentagonal

five-sided.

perennial

living several years.

perianth

the calyx and corolla collectively.

persistent

remaining long attached, as leaves over winter or a calyx after flowering season.

petal

one of the individual parts of the corolla, usually leaflike and brightly colored.

petiole

the stem or stalk of a leaf.

pilose

hairy; with soft slender hairs.

pirmate

having branches, lobes, leaflets or veins arranged on opposite sides of a common axis.

pinnate compound leaf compound with the leaflets arranged on each side of the rachis.

pistil

the seed-producing, innermost portion of a flower.

pistillate flower

a flower with pistils; without stamens.

pith

the softer central part of a twig or stem.

pitted

with small depressed areas.

plane

with a flat, smooth surface.

pome

a fleshy fruit resulting from the development of an inferior ovary and a fleshy receptacle, like an apple, pear or quince.

pruinose

frosted; covered with a waxy powdery secretion on the surface; having a "bloom".

puberulent

minutely pubescent; with fine short or almost imperceptible down.

pubescent

hairy or downy; covered with short, soft hairs.

pyramidal

shaped like a pyramid.

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R

raceme a flower cluster with an elongated main axis but with flowers borne on pedicels of equal length.

rachis

the central axis of a spike, raceme or compound leaf.

rank

a row.

receptacle

the portion of a flower bearing the sepals, petals, etc.; the expanded portion of an axis supporting a flower head.

recurved

curved backward or downward.

reflexed

bent abruptly backward.

resin duct

long narrow channel filled with resin.

reticulate

forming a network.

rhomboidal approaching the shape of a rhombus, i.e., with the outline of an equilateral parallelogram with oblique angles. In a rhomboid only opposite sides are equal.

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S

sagittate

arrowhead-shaped.

samara

an indehiscent winged fruit with a single seed as in maple, elm or ash.

scabrous

rough to the touch.

scale

a tiny leaf, usually appressed and dry, i.e., a modified leaf covering part of a bud, of a cone or a catkin; a bark flake; a tiny, flattened epidermal outgrowth.

scarious

thin, dry, membranaceous.

scurfy

covered with small bran-like scales.

sepal

one of the individual parts of the calyx.

serrate

a margin armed with sharp teeth which point forward like the teeth of a saw.

serrulate

finely serrate.

sessile

without a stalk.

shrub

a low branching plant without a main stem.

simple

of one piece; not compound, used to describe a fruit derived from a single ovary, a leaf with a single blade, etc.

sinewy

fluted; with strongly developed fluting.

sinus

a space or hole; a cleft or recess.

spatulate oblong, wide and rounded at the apex but gradually narrowed near the base.
spike an inflorescence like a raceme but with the flowers sessile.

spindle-shaped

broader in the middle, tapering at each end.

spine

a sharp, woody or rigid outgrowth from a stem; sometimes a modified leaf or stipule; sometimes same as thorn.

spur

a short, slowly-grown branchlet; a hollow sac-like or tubular extension of some part of a flower, usually producing nectar.

stamen

the pollen-bearing organ of a flower, normally consisting of a stalk called the filament and a pollenbearing portion known as the anther.

staminate flower

a flower with stamens but usually without pistils.

stellate

star-like; when several similar parts spread out from a common center.

stigma

the roughened or sticky part of the pistil which receives the pollen.

stipular spine

a spine formed from a stipule.

stipule

an appendage, often leaf-like and usually paired, found at the base of a petiole or leaf.

stipule scar

the scar left by the fall of a stipule.

stolon

a runner or long branch arising at the base of a plant and taking root.

stoloniferous

producing stolons.

striate

marked with fine longitudinal lines or ridges.

style

the part of a pistil connecting the ovary with the stigma.

sub

a prefix applied to many botanical terms meaning more or less, or somewhat; below.

subtended

lying under or opposite to.

subulate

awl-shaped; tapering from a thicker base to a sharp point, the sides usually concave.

succulent

juicy; fleshy.

superposed bud

an accessory bud found above the main axillary bud.

supra

axillary; located above an axil.

suture

a junction or seam of union; a line of opening or dehiscence.

symmetrical

balanced; with mirror image parts.

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T

terete

circular in cross section.

terminal bud

the end bud, by which a stem continues its growth.

thorn

a degenerated, sharp-pointed branch.

thyrsiform

an inflorescence shaped like that of a lilac or bunch of grapes.

tomentose

with dense matted hairs.

tomentum

matted woolly hairs.

toothed

furnished with short projections, especially when these are sharp.

tridentate

having three teeth, prongs or points.

tri-pinnately compound

thrice pinnately compound.

truncate

ending abruptly as though cut off.

tubercle

a small projection, knob or swelling.

tuberculate

with rounded projections or tubercles.

twig

a young shoot of the past season.

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U

umbel a flower cluster where the pedicels arise from a common point and the pedicels are of nearly equal length, forming an umbrella-like inflorescence.

unarmed

without spines, prickles and the like.

undulate

wavy.

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V

valvate

opening by valves; used to refer to bud scales meeting along the margins only.

valve

one of the pieces into which a dehiscent pod, or any similar structure, splits; one of the parts into which a capsule splits.

vein

one of the branches of the framework of a leaf; a "thread" of fibro-vascular tissue in a leaf or other flat structure.

villous

covered with long soft hairs.

viscid

sticky.

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W

whorl

an arrangement of three or more leaves or branches radiating from the same node; a circle of structures around a stem.

wing

any membranous or thin expansion bordering or surrounding a structure.

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