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Glossary of Some Technical Terms

acuminate
an apex (such at the tip of a leaf) with sides gradually concave and tapering to a point
acute
tapering to an apex with more or less straight sides
alternate
parts (as leaves) situated one at a node
aril
tissue that forms a fleshy covering of the seed, as in Taxum and Torreya, or rudimentary at the base of the fleshy seed, as in Cephalotaxus
bristle
stiff hair
bud scale
covering which protects the embryonic tissue of a bud
calyx
the outer set of segments (sepals) or envelope of a flower; usually green in color and smaller than the inner set (i e , petals)
cordate
heart-shaped, with the notch at the base
compound
subdivided into several distinct parts; such as leaflets in a compound leaf (e.g., black walnut).
crenate-serrate
having a mixture of blunt and sharp teeth
crenate
rounded teeth on a margin
crenulate
very small rounded teeth on a margin
cuneate
wedge-shaped; triangular and tapering to a point at the base
cyme
a flat or round-topped determinate inflorescence, in which the terminal flower blooms first
dentate
having marginal teeth whose apices are perpendicular to the margin and do not point forward
dioecious
flowers imperfect, the staminate (male) and pistillate (female) flowers borne on different plants
double flower
one with more than the usual number of petals, colored sepals or bracts (frequently double the usual number)
doubly serrate
serrations bearing minute teeth on margin
elliptic
in the shape of an ellipse, or a narrow oval; broadest at the middle and narrower at the two equal ends
emarginate
slight notch at the an apex
entire
having a margin without teeth or crenations
fastigiate
branches erect and close together
glabrous
not hairy (A glabrous surface need not be smooth, it could be bumpy )
glaucous
covered with a waxy bloom which rubs off easily (e g bloom on a blueberry fruit)
globose
round or spherical
hairy
pubescent with longer hairs
herbaceous
lacking a persistent woody stem above ground
hip
the fruit of a rose
imbricated
overlapping, such as roof shingle
imperfect flowers
one that lacks either stamens (the male parts) or pistils (the female parts)
indeterminate
describes an inflorescence in which the lower or outer flowers bloom first, thus allowing indefinite elongation of the main axis
inflorescence
a flower cluster; the arrangement of the flowers on the flowering axis
internode
the part of a stem between nodes
lanceolate
lance-shaped; much longer than wide, with the widest point below the middle and tapering to the apex
lateral bud
a bud borne in the axil of a leaf
leaf scar
the mark on a twig after a leaf falls
lenticel
a small corky spot on young bark made of loosely packed cells
linear
resembling a line; long and narrow with more or less parallel sides
lustrous
having a slight metallic gloss, less reflective than glossy
midrib
the primary-rib or mid-vein of a leaf
monoecious
flowers imperfect, the staminate (male) and pistillate (flowers) borne of the same plant (compare dioecious)
mucronate
abruptly terminated by a sharp point, a mucro
naked bud
one without scales
nodding
drooping, bending over
node
a joint on a stem (point of origin of a leaf or bud)
ob-
a prefix indicating the inverse
oblong
longer than broad, rectangular, sides more or less parallel
obovate
the inverse of ovate, broadest above the middle
ocrea (ochrea)
a tubular stipule or a pair of stipules united into a sheath
opposite
two parts (such as leaves) at a node
ovate
egg-shaped in outline; broadest below the middle, oval-like
ovoid
an egg-shaped three dimensional solid
ovule
the egg-containing unit of the ovary, develops into the seed
palmate
radiating fan-like from a common point
panicle
a branched indeterminate inflorescence [flower cluster] with flowers maturing from the bottom upwards
perfect flowers
have both functional stamens (male parts) and pistils (female parts)
petiole
the leaf stalk
petiolule
the stalk of a leaflet
pith
the soft tissue in inner central portion of a stem
pinnate
segments along each side of a common axis
polygamous
bearing unisexual and bisexual flowers on the same plant
prickle
a small, sharp, outgrowth of the epidermis or bark (compare spine and thorn)
prostrate
lying flat on the ground, a general term
proximal
toward the base
pubescent
covered with short hairs, a general term
raceme
an unbranched, elongated inflorescence with flowers maturing from the bottom upwards
samara
a dry indehiscent fruit bearing a wing, Examples: ash, maple
sepal
a division of the calyx; the outermost floral organs
sessile
without a stalk
serrate
saw toothed, teeth pointing forward
serrulate
minutely serrate
simple
undivided, as a leaf blade which in not separated into separate leaflets (e.g., elm leaf), (though the blade may be deeply lobed as in many maple leaves), compare to the term, compound.
spine
a stiff, slender, sharp-pointed structure arising from below the epidermis; representing a modified leaf or stipule. Sometime applied to structure with the appearance of a true spine.
thorn
a stiff, woody, modified stem with a sharp point, sometimes applied to anything resembling a true thorn (see spine and prickle).
tomentose
densely woolly, hairs soft and matted
tomentum
dense matted hairs
torus
the recepticle of a flower (in blackberries it remains with the fruit when picked)
trifoliate
three leaved; or a leaf with three leaflets (correct term is actually trifoliolate)
truncate
as if cut off at right angels to the primary axis
umbel
an unbranched inflorescence in which the stalks (pedicels) arise from a common point, like the struts of an umbrella
undulate
wavy, said of a margin
var.
and abbreviation of variety, Latin varietas. In the botanical sense, variety is a population of plants of a species that display marked differences in nature, and these differences are transmitted by seed (i e , inherited).   Sometimes subspecies (abbreviated ssp ) is used in place of variety.   Their use depends upon the taxonomic "school" of the writer.