Glossary of leaf morphology

File:Leaf morphology.svg

Chart illustrating leaf morphology terms

The following terms are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (that is, the leaf blade or 'lamina' is undivided) or compound (that is, the leaf blade is divided into two or more leaflets).<ref name=":0">Template:Cite book</ref> The edge of the leaf may be regular or irregular, and may be smooth or have hair, bristles, or spines. For more terms describing other aspects of leaves besides their overall morphology see the leaf article.

The terms listed here all are supported by technical and professional usage, but they cannot be represented as mandatory or undebatable; readers must use their judgement. Authors often use terms arbitrarily, or coin them to taste, possibly in ignorance of established terms, and it is not always clear whether because of ignorance, or personal preference, or because usages change with time or context, or because of variation between specimens, even specimens from the same plant.Template:Citation needed For example, whether to call leaves on the same tree "acuminate", "lanceolate", or "linear" could depend on individual judgement, or which part of the tree one collected them from. The same cautions might apply to "caudate", "cuspidate", and "mucronate", or to "crenate", "dentate", and "serrate".

Another problem is to establish definitions that meet all cases or satisfy all authorities and readers. For example, it seems altogether reasonable to define a mucro as "a small sharp point as a continuation of the midrib", but it may not be clear how small is small enough, how sharp is sharp enough, how hard the point must be, and what to call the point when one cannot tell whether the leaf has a midrib at all. Various authors or field workers might come to incompatible conclusions, or might try to compromise by qualifying terms so vaguely that a description of a particular plant practically loses its value.

Use of these terms is not restricted to leaves, but may be applied to morphology of other parts of plants, e.g. bracts, bracteoles, stipules, sepals, petals, carpels or scales. Some of these terms are also used for similar-looking anatomical features on animals.

Leaf structure

Leaves of most plants include a flat structure called the blade or lamina supported by a network of veins, a petiole and a leaf base;<ref name=":0" /> but not all leaves are flat, some are cylindrical.Template:Citation needed Leaves may be simple, with a single leaf blade, or compound, with several leaflets. Compound leaves may be pinnate with pinnae (leaflets) on both sides of a rachis (axis), or may be palmate with multiple leaflets arising from a single point.<ref name=":0" /> Leaf structure is described by several terms that include:

File:Bipinnate leaf anatomy with alternate labels.jpg

Bipinnate leaf anatomy with labels showing alternative usages

File:Leaf morphology type ternately-compound palmate-ternate sessile.png

A ternate compound leaf with a petiole but no rachis (or rachillae)

Image	Term	Latin	Description
File:Leaf morphology Bifoliolate.png	[[wikt:bifoliolate|Template:Vanchor]]		Having two leaflets<ref>Template:Cite book</ref>
	Template:Vanchor
	Template:Vanchor
File:Leaf morphology Bigeminate.png	[[wikt:bigeminate|Template:Vanchor]]		Having two leaflets, each leaflet being bifoliolate
File:Leaf morphology bipinnate.png	[[wikt:bipinnate|Template:Vanchor]]	lang}}	The leaflets are themselves pinnately-compound; twice pinnate<ref name=":0" /> see imparipinnate and paripinnate
File:Leaf morphology Biternate.png	[[wikt:biternate|Template:Vanchor]]		With three components, each with three leaflets<ref name=":0" />
File:Leaf morphology odd pinnate.png	[[wikt:imparipinnate|Template:Vanchor]]		With an odd number of leaflets, pinnate with a terminal leaflet (the opposite of paripinnate)<ref name=":0" />
	Template:Vanchor
File:Leaf morphology even pinnate.png	Template:Anchor[[wikt:paripinnate|Template:Vanchor]]		Pinnate with an even number of leaflets, lacking a terminal leaflet (the opposite of imparipinnate)<ref name=":0" />
	even-pinnate
File:Leaf morphology Palmately compound.png	[[wikt:palmate|Template:Vanchor]]	palmatus	Consisting of leaflets all radiating from one point
File:Leaf morphology Acute.png	Template:Anchor simple		Leaf blade in one continuous section, without leaflets (not compound)<ref name=":0" />
File:Leaf morphology trifoliolate.png	[[wikt:ternate|Template:Vanchor]]	lang}}	With three leaflets<ref name=":0" />
	[[wikt:trifoliate|Template:Vanchor]]	lang}}
	[[wikt:trifoliolate|Template:Vanchor]]	lang}}
File:Leaf morphology tripinnate.png	[[wikt:tripinnate|Template:Vanchor]]	lang}}	Pinnately compound in which each leaflet is itself bipinnate<ref name=":0" />

Leaf and leaflet shapes

Being one of the more visible features, leaf shape is commonly used for plant identification. Similar terms are used for other plant parts, such as petals, tepals, and bracts.

File:Cilantro leaf.jpg

Oddly pinnate, pinnatifid leaves (Coriandrum sativum, coriander or cilantro)

File:Hibiscus mutabilis 5.JPG

Partial chlorosis revealing palmate venation in simple leaves of Hibiscus mutabilis

Image	Term	Latin	Refers principally to	Description
File:Leaf morphology acicular.png	Template:Vanchor	lang}}	whole leaf	Slender and pointed, needle-like
File:Leaf morphology acuminate.png	Template:Vanchor	lang}}	leaf tip	Tapering to a long point in a concave manner
File:Leaf morphology Acute.png	Template:Vanchor		leaf tip or base	Pointed, having a short sharp apex angled less than 90°
File:Leaf morphology Apiculate.png	Template:Vanchor	lang}}	leaf tip	Tapering and ending in a short, slender point
File:Leaf morphology aristate.png	Template:Vanchor	lang}}	leaf tip	Ending in a stiff, bristle-like point
	Template:Vanchor		whole leaf	With the blade shape different on each side of the midrib
File:Leaf morphology Attenuate.png	Template:Vanchor	lang}}	leaf base	Having leaf tissue taper down the petiole to a narrow base and always having some leaf material on each side of the petiole
File:Leaf morphology base auriculate (cropped).png	Template:Vanchor	lang}}	leaf base	Having ear-shaped appendages reaching beyond the attachment to the petiole or stem (in case of a seated leaf)
File:Leaf morphology Caudate.png	Template:Vanchor	lang}}	leaf tip	Tailed at the apex
	Template:Vanchor, Template:Vanchor		leaf tip	Having a rachis that extends beyond the leaf blade or leaflets into a long whip-like extension or cirrus (common in climbing palms); antonym: ecirrate
File:Leaf morphology cordate.png	Template:Vanchor, Template:Vanchor	lang}}	whole leaf or base	Heart-shaped, with the petiole or stem attached to the notch
File:Leaf morphology cuneate.png	Template:Vanchor	lang}}	leaf base	Triangular, wedge-shaped, stem attaches to point
	Template:Vanchor		whole leaf	Narrowly triangular, widest on the opposite end from the stem, with the corners at that end rounded
File:Handdrawn Cuspidate.png	Template:Vanchor	lang}}	leaf tip	With a sharp, elongated, rigid tip; tipped with a cusp
File:Leaf morphology deltoid.png	Template:Vanchor, Template:Vanchor	lang}}	whole leaf	Shaped like the Greek letter delta; triangular with stem attached to side
File:Leaf morphology digitate.png	Template:Vanchor	lang}}	whole leaf	A palmately compound leaf with leaflets, similar to palmate<ref>Index of Garden Plants, Mark Griffiths, Timber Press, 1992</ref>
	Template:Vanchor		leaf tip	Without a cirrus; antonym: cirrate
File:Leaf morphology elliptic.png	Template:Vanchor	lang}}	whole leaf	Shaped like an ellipse (widest at mid-blade and with similar convex tapering towards apex and base), with a short or no point
File:Leaf morphology apex emarginate.png	Template:Vanchor	lang}}	leaf tip	Slightly indented at the tip
File:Leaf morphology ensiforme.PNG	Template:Vanchor	lang}}	whole leaf	Shaped like a sword; long and narrow with a sharp pointed tip
File:Leaf morphology falcate.png	Template:Vanchor	lang}}	whole leaf	Sickle-shaped
File:Leaf morphology Fenestrate.png	Template:Vanchor	lang}}	leaf surface features	Large openings through the leaf; see perforate; sometimes used to describe leaf epidermal windows
File:Plant morphology solid filiform.png	Template:Vanchor	lang}}	whole leaf	Thread- or filament-shaped
File:Leaf morphology flabelate.png	Template:Vanchor	lang}}	whole leaf	Semi-circular or fan-like
File:Leaf morphology hastate.png	Template:Vanchor	lang}}	whole leaf or base	Spear-shaped: pointed, with barbs, shaped like a spear point, with flaring pointed lobes at the base
File:Leaf morphology division laciniate.png	Template:Vanchor	lacinatus	whole leaf	Very deeply lobed with the lobes being very drawn out and often making the leaf look somewhat like a branch or a pitchfork
	Template:Vanchor		3-D shape	Flat (like most leaves)
File:Leaf morphology lanceolate.png	Template:Vanchor	lang}}	whole leaf	Long, wider in the middle, shaped like a lance tip
File:Leaf morphology linear.png	Template:Vanchor	lang}}	whole leaf	Long and very narrow like a blade of grass
File:Leaf morphology lobed.png	Template:Vanchor	lang}}	whole leaf	Being divided by clefts; may be pinnately lobed or palmately lobed
File:Leaf morphology Lorate.png	Template:Vanchor	lang}}	whole leaf	Having the form of a thong or strap
File:Leaf morphology Lyrate.png	Template:Vanchor	lang}}	whole leaf	Shaped like a lyre, pinnately lobed leaf with an enlarged terminal lobe and smaller lateral lobes. See also List of lyrate plants.
File:Leaf morphology Mucronate.png	Template:Vanchor	mucronatus	leaf tip	Ending abruptly in a small sharp point as a continuation of the midrib<ref>Mucronate Template:Webarchive, Answers.com, from Roget's Thesaurus.</ref>
File:Leaf morphology multifide.svg	Template:Vanchor	lang}} + {{#invoke:Lang|lang}}	whole leaf	Cleft into many parts or lobes
File:Leaf morphology obcordate.png	Template:Vanchor	lang}}	whole leaf	Heart-shaped, stem attaches at the tapering end
File:Leaf morphology oblanceolate.png	Template:Vanchor	lang}}	whole leaf	Much longer than wide and with the widest portion near the tip; reversed lanceolate
File:Leaf morphology oblique.png	Template:Vanchor		leaf base	Asymmetrical leaf base, with one side lower than the other
File:Leaf morphology oblong.png	Template:Vanchor	lang}}	whole leaf	Having an elongated form with slightly parallel sides; roughly rectangular
File:Leaf morphology obovate.png	Template:Vanchor	lang}}	whole leaf	Teardrop-shaped, stem attaches to the tapering end; reversed ovate
	Template:Vanchor		whole leaf	Reversed trullate; the longer sides meet at the base rather than the apex.
File:Leaf morphology obtuse.png	Template:Vanchor	lang}}	leaf tip or base	Blunt, forming an angle > 90°
File:Leaf morphology orbicular.png	Template:Vanchor	lang}}	whole leaf	Circular
File:Leaf morphology ovale.png	Template:Vanchor	lang}}	whole leaf	Egg-shaped, with a tapering point and the widest portion near the petiole
File:Leaf morphology palmate.png	Template:Vanchor	lang}}	whole leaf	citation	CitationClass=web }}</ref>
File:Palmatilobé.svg	Template:Vanchor	lang}}	whole leaf	citation	CitationClass=web }}</ref>
File:Palmatifide.svg	Template:Vanchor	lang}} + {{#invoke:Lang|lang}}	whole leaf	Palm-shaped, having lobes with incisions that extend less than halfway toward the petiole
File:Palmatipartite.svg	Template:Vanchor	lang}} + {{#invoke:Lang|lang}}	whole leaf	Having palmate lobes with incisions that extend over halfway toward the petiole
File:Palmatiséquée.svg	Template:Vanchor	lang}} + {{#invoke:Lang|lang}}	whole leaf	Having palmate lobes with incisions that extend almost up, but not quite to the petiole.
File:Leaf morphology pandurate.png	Template:Vanchor	panduratus	whole leaf	Fiddle-shaped; obovate with a constriction near the middle.
File:Leaf morphology pedate.png	Template:Vanchor	lang}}	whole leaf	Palmate, with cleft lobes<ref>Template:Cite book</ref>
File:Leaf morphology peltate.png	Template:Vanchor	lang}}	stem attachment	A round leaf where the petiole attaches near the center, e.g. a lotus leaf
File:Leaf morphology attachment connate-perfoliate.png	Template:Vanchor	lang}}	stem attachment	With the leaf blade surrounding the stem such that the stem appears to pass through the leaf
File:Leaf morphology Perforate.png	Template:Vanchor	lang}}	leaf surface features	Many holes, or perforations, on leaf surface. Compare with fenestrate.
File:Pennatilobé.svg	Template:Vanchor	lang}} + {{#invoke:Lang|lang}}	whole leaf	Having lobes pinnately arranged on the central axis
File:Pennatifide.svg	Template:Vanchor	lang}} + {{#invoke:Lang|lang}}	whole leaf	Having lobes with incisions that extend less than halfway to the midrib
File:Pennatipartite2.svg	Template:Vanchor	lang}} + {{#invoke:Lang|lang}}	whole leaf	Having lobes with incisions that extend more than halfway to the midrib
File:Pennatiséquée.svg	Template:Vanchor	lang}} + {{#invoke:Lang|lang}}	whole leaf	Having lobes with incisions that extend almost to, or up to, the midrib
File:Leaf morphology reniform.png	Template:Vanchor	lang}}	whole leaf	Shaped like a kidney, with an inward curve on one side
File:Leaf morphology apex retuse.png	Template:Vanchor		leaf tip	With a shallow notch in a round apex
File:Leaf morphology rhomboid.png	Template:Vanchor, Template:Vanchor	lang}}	whole leaf	Diamond-shaped
File:Leaf morphology apex rounded.png	Template:Vanchor	lang}}	leaf tip or base	Circular, no distinct point
	semiterete		3-D shape	Rounded on one side and flat on the other
File:Leaf morphology spear-shaped.png	Template:Vanchor	lang}}	whole leaf	Arrowhead-shaped with the lower lobes folded, or curled downward
File:Leaf morphology spatulate.png	Template:Vanchor	lang}}	whole leaf	Spoon-shaped; having a broad flat end which tapers to the base
File:Leaf morphology hastate.png	Template:Vanchor-shaped	lang}}	whole leaf	See hastate.
File:Leaf morphology subobtuse.png	Template:Vanchor	lang}}	leaf tip or base	Somewhat blunted; neither blunt nor sharp
File:Leaf morphology subulate.png	Template:Vanchor	lang}}	leaf tip	Awl-shaped with a tapering point
File:Plant morphology solid terete.png	Template:Vanchor		3-D shape	Cylindrical with a circular or distorted circular cross-section and a single surface wrapping around it with no grooves or ridges. Subterete means the leaves are not completely terete, as seen in various lichens and succulents.
File:Leaf morphology trullate.png	Template:Vanchor		whole leaf	Shaped like a masonry trowel
File:Leaf morphology truncate.png	Template:Vanchor	lang}}	leaf tip or base	With a squared-off end
	Template:Vanchor	lang}}	3-D shape	Wave-like
File:Leaf morphology unifoliate.png	Template:Vanchor	lang}}	compound leaves	With a single leaflet; it is distinct from a simple leaf by the presence of two abscission layers and often by petiolules and stipels.

Edge

Leaf margins (edges) are frequently used in visual plant identification because they are usually consistent within a species or group of species, and are an easy characteristic to observe. Edge and margin are interchangeable in the sense that they both refer to the outside perimeter of a leaf.

Image	Term	Latin	Description
File:Leaf morphology entire.png	Template:AnchorTemplate:Anchorentire	Forma integra	Even; with a smooth margin; without toothing
File:Leaf morphology ciliate.png	Template:AnchorTemplate:Anchorciliate	ciliatus	Fringed with hairs
File:Leaf morphology crenate.png	Template:AnchorTemplate:Anchorcrenate	crenatus	Wavy-toothed; dentate with rounded teeth
	Template:AnchorTemplate:Anchorcrenulate	crenulatus	Finely crenate
	Template:AnchorTemplate:Anchorcrisped	crispus	Curly
File:Leaf morphology dentate.png	Template:AnchorTemplate:Anchordentate	dentatus	Toothed; may be Template:Anchorcoarsely dentate, having large teeth or Template:Anchorglandular dentate, having teeth which bear glands
File:Leaf morphology denticulate.png	Template:AnchorTemplate:Anchordenticulate	denticulatus	Finely toothed
File:Leaf morphology doubly serrate.png	Template:AnchorTemplate:Anchordoubly serrate	duplicato-dentatus	Each tooth bearing smaller teeth
File:Leaf morphology serrate.png	Template:AnchorTemplate:Anchorserrate	serratus	Saw-toothed; with asymmetrical teeth pointing forward
File:Leaf morphology serrulate.png	Template:AnchorTemplate:Anchorserrulate	serrulatus	Finely serrate
File:Leaf morphology sinuate.png	Template:AnchorTemplate:Anchorsinuate	sinuosus	With deep, wave-like indentations; coarsely crenate
File:Leaf morphology lobate.png	Template:AnchorTemplate:Anchorlobate	lobatus	Indented, with the indentations not reaching the center
File:Leaf morphology undulate.png	Template:AnchorTemplate:Anchorundulate	undulatus	With a wavy edge, shallower than sinuate
File:Leaf morphology spiny.png	Template:AnchorTemplate:Anchorspiny or Template:Anchorpungent	spiculatus	With stiff, sharp points such as thistles

Leaf folding

Leaves may also be folded, sculpted or rolled in various ways. If the leaves are initially folded in the bud, but later unrolls it is called vernation, ptyxis is the folding of an individual leaf in a bud.

Image	Term	Latin	Description
	Template:Vanchor or keeled	carinatus	With a longitudinal ridge, keel-shaped
File:Peperomia dolabriformis.jpg	Template:Vanchor		Folded upwards, with the surfaces close to parallel
File:Mimetes fimbrifolius (5211424654).jpg	Template:Vanchor		Forming a hood, margins and tip curved downward
File:Involute vernation.jpg	Template:Vanchor		Rolled upwards (towards the adaxial surface)
File:Palm leaf washingtonia robusta.jpg	Template:Vanchor	plicatus	With parallel folds
	Template:Vanchor		Folded downwards, with the surfaces close to parallel
File:Ledum groenlandicum.jpg	Template:Vanchor		Rolled downwards (towards the abaxial surface)
	Template:Vanchor		Opposing left and right halves of lamina folded along longitudinal axis, with one half rolled completely within the other

Latin descriptions

The Latin word for 'leaf', {{#invoke:Lang|lang}}, is neuter. In descriptions of a single leaf, the neuter singular ending of the adjective is used, e.g. {{#invoke:Lang|lang}} 'lanceolate leaf', {{#invoke:Lang|lang}} 'linear leaf'. In descriptions of multiple leaves, the neuter plural is used, e.g. {{#invoke:Lang|lang}} 'linear leaves'. Descriptions commonly refer to the plant using the ablative singular or plural, e.g. {{#invoke:Lang|lang}} 'with ovate leaves'.Template:Sfnp

See also

• Glossary of botanical terms
• Glossary of plant morphology
• Cladophylls are leaf-like petioles
• Leaf size
• Sinus
• Leaflet (botany) and Rachis
• Petiole (botany) and Plant stem
• Phylloclades are flattened stems that resemble leaves
• Pinnation
• Plant morphology
• Taxonomy (biology)

Bibliography

• Template:Cite book
• {{#invoke:citation/CS1|citation

|CitationClass=web }}, in Template:Harvtxt

• {{#invoke:citation/CS1|citation

|CitationClass=web }}, in Template:Harvtxt

• {{#invoke:citation/CS1|citation

|CitationClass=web }} Template:Refend

External links

• The Description of Leaves, University of Rochester
• Fairchild Tropical Botanic Garden
• Vplants
• Botany 115 Template:Webarchive
• The seed site