Leaf taxonomy

Teriminology related to leaves:

In botany, leaf shape is characterized with the following terms (botanical Latin terms in brackets):

Acicular (acicularis): Slender and pointed, needle-like

Acuminate (acuminata): Tapering to a long point

Aristate (aristata): Ending in a stiff, bristle-like point

Bipinnate (bipinnata): Each leaflet also pinnate

Compound: The combination of one leaflet arrangement within an arrangement at a larger level; e.g.:"bipinnate, twice-pinnate: the leaflets are themselves pinnately-compound"

Cordate (cordata): Heart-shaped, stem attaches to cleft

Cuneate (cuneata): Triangular, stem attaches to point

Deltoid (deltoidea) or deltate: Triangular, stem attaches to side

Digitate (digitata): Divided into finger-like lobes

Elliptic (elliptica): Oval, with a short or no point

Falcate (falcata): sickle-shaped

Filiform (filiformis): thread- or filament-shaped

Flabellate (flabellata): Semi-circular, or fan-like

Hastate, spear-shaped (hastata): Pointed, with barbs, shaped like a spear point, with flaring pointed lobes at the base

A single laciniate leaf of Adenanthos sericeusLaciniate: Very deeply lobed, the lobes being very drawn out, often making the leaf look somewhat like a branch

Lance-shaped, lanceolate (lanceolata): Long, wider in the middle

Linear (linearis): Long and very narrow

Lobed (lobata): With several points

Obcordate (obcordata): Heart-shaped, stem attaches to tapering point

Oblanceolate (oblanceolata): Top wider than bottom

Oblong (oblongus): Having an elongated form with slightly parallel sides
Obovate (obovata): Teardrop-shaped, stem attaches to tapering point

Obtuse (obtusus): With a blunt tip

Orbicular (orbicularis): Circular

Ovate (ovata): Oval, egg-shaped, with a tapering point

Palmate (palmata): consisting of leaflets[1] or lobes[2] radiating from the base of the leaf.

Pedate (pedata): Palmate, with cleft lobes

Peltate (peltata): Rounded, stem underneath

Perfoliate (perfoliata): Stem through the leaves

Pinnate (pinnata): Two rows of leaflets

odd-pinnate, imparipinnate: pinnate with a terminal leaflet

paripinnate, even-pinnate: pinnate lacking a terminal leaflet

pinnatifid and pinnatipartite: leaves with pinnate lobes that are not discrete, remaining sufficiently connected to each other that they are not separate leaflets.

bipinnate, twice-pinnate: the leaflets are themselves pinnately-compound

tripinnate, thrice-pinnate: the leaflets are themselves bipinnate

tetrapinnate: the leaflets are themselves tripinnate.

Pinnatisect (pinnatifida): Cut, but not to the midrib (it would be pinnate then)

Reniform (reniformis): Kidney-shaped

Rhomboid (rhomboidalis): Diamond-shaped

Round (rotundifolia): Circular

Sagittate (sagittata): Arrowhead-shaped

Spear-shaped: see Hastate.

Spatulate, spathulate (spathulata): Spoon-shaped

Subulate (subulata): Awl-shaped with a tapering point

Sword-shaped (ensiformis): Long, thin, pointed

Trifoliate (or trifoliolate), ternate (trifoliata): Divided into three leaflets

Tripinnate (tripinnata): Pinnately compound in which each leaflet is itself bipinnate

Truncate (truncata): With a squared off end

Unifoliate (unifoliata): with a single leaf

Edge

ciliate: fringed with hairs

crenate: wavy-toothed; dentate with rounded teeth, such as Fagus (beech)

crenulate finely or shallowly crenate

dentate: toothed, such as Castanea (chestnut)

coarse-toothed: with large teeth

glandular toothed: with teeth that bear glands.

denticulate: finely toothed

doubly toothed: each tooth bearing smaller teeth, such as Ulmus (elm)

entire: even; with a smooth margin; without toothing

lobate: indented, with the indentations not reaching to the center, such as many Quercus (oaks)

palmately lobed: indented with the indentations reaching to the center, such as Humulus (hop).

serrate: saw-toothed with asymmetrical teeth pointing forward, such as Urtica (nettle)

serrulate: finely serrate

sinuate: with deep, wave-like indentations; coarsely crenate, such as many Rumex (docks)

spiny: with stiff, sharp points, such as some Ilex (hollies) and Cirsium (thistles).

Tip

Leaves showing various morphologies. Clockwise from upper left: tripartite lobation, elliptic with serrulate margin, peltate with palmate venation, acuminate odd-pinnate (center), pinnatisect, lobed, elliptic with entire marginacuminate: long-pointed, prolonged into a narrow, tapering point in a concave manner.

acute: ending in a sharp, but not prolonged point

cuspidate: with a sharp, elongated, rigid tip; tipped with a cusp.

emarginate: indented, with a shallow notch at the tip.

mucronate: abruptly tipped with a small short point, as a continuation of the midrib; tipped with a mucro.

mucronulate: mucronate, but with a smaller spine.

obcordate: inversely heart-shaped, deeply notched at the top.

obtuse: rounded or blunt

truncate: ending abruptly with a flat end, that looks cut off.

Base

acuminate: coming to a sharp, narrow, prolonged point.

acute: coming to a sharp, but not prolonged point.

auriculate: ear-shaped.

cordate: heart-shaped with the notch towards the stalk.

cuneate: wedge-shaped.

hastate: shaped like an halberd and with the basal lobes pointing outward.

oblique: slanting.

reniform: kidney-shaped but rounder and broader than long.

rounded: curving shape.

sagittate: shaped like an arrowhead and with the acute basal lobes pointing downward.

truncate: ending abruptly with a flat end, that looks cut off.

Surface

Scale-shaped leaves of a Norfolk Island Pine, Araucaria heterophylla.farinose: bearing farina; mealy, covered with a waxy, whitish powder.

glabrous: smooth, not hairy.

glaucous: with a whitish bloom; covered with a very fine, bluish-white powder.

glutinous: sticky, viscid.

papillate, or papillose: bearing papillae (minute, nipple-shaped protuberances).

pubescent: covered with erect hairs (especially soft and short ones).

punctate: marked with dots; dotted with depressions or with translucent glands or colored dots.

rugose: deeply wrinkled; with veins clearly visible.

scurfy: covered with tiny, broad scalelike particles.

tuberculate: covered with tubercles; covered with warty prominences.

verrucose: warted, with warty outgrowths.

viscid, or viscous: covered with thick, sticky secretions.

Hairiness

"Hairs" on plants are properly called trichomes. Leaves can show several degrees of hairiness. The meaning of several of the following terms can overlap.

arachnoid, or arachnose: with many fine, entangled hairs giving a cobwebby appearance.

barbellate: with finely barbed hairs (barbellae).

bearded: with long, stiff hairs.

bristly: with stiff hair-like prickles.

canescent: hoary with dense grayish-white pubescence.

ciliate: marginally fringed with short hairs (cilia).

ciliolate: minutely ciliate.

floccose: with flocks of soft, woolly hairs, which tend to rub off.

glabrous: no hairs of any kind present.

glandular: with a gland at the tip of the hair.

hirsute: with rather rough or stiff hairs.

hispid: with rigid, bristly hairs.

hispidulous: minutely hispid.

hoary: with a fine, close grayish-white pubescence.

lanate, or lanose: with woolly hairs.

pilose: with soft, clearly separated hairs.

puberulent, or puberulous: with fine, minute hairs.

pubescent: with soft, short and erect hairs.

scabrous, or scabrid: rough to the touch.

sericeous: silky appearance through fine, straight and appressed (lying close and flat) hairs.

silky: with adpressed, soft and straight pubescence.

stellate, or stelliform: with star-shaped hairs.

strigose: with appressed, sharp, straight and stiff hairs.

tomentose: densely pubescent with matted, soft white woolly hairs.

cano-tomentose: between canescent and tomentose.

felted-tomentose: woolly and matted with curly hairs.

villous: with long and soft hairs, usually curved.

woolly:' with long, soft and tortuous or matted hairs.