Types of Root Systems Plants have three types of root systems: 1.) taproot, with a main taproot that is larger and

grows faster than the branch roots; 2.) fibrous, with all roots about the same size;

3.) adventitious, roots that form on any plant part other than the roots. Fibrous systems

are characteristic of grasses and are shallower than the taproot systems found on most

eudicots and many gymnosperms.

Modifications of Roots Roots are modified into different forms to perform specific functions other than their normal functions.

Modification in roots is found in both tap root system and adventitious root system.

Modification in root occurs when there occurs a permanent change in the structure of the root system.

This change in structure of the tap root or the adventitious root system is for carry out certain specific

functions additional to anchorage and absorption. The change in the structure of the roots is for

adaptation to their surrounding environment.

Tap Root Modifications Back to Top

Tap roots are modified in to different structures, these modified structures carry out specific functions like food storage. Such roots are referred to as modified tap roots. They are different types of modified tap roots like Fusiform, Napiform, Conical, Tuberous or tubercular roots, pneumatophores.

Fusiform : Fusiform is a modified tap root. The primary root of the system is swollen at the middle and

tapers gradually at both the ends forming a spindle shaped structure. Example of fusiform roots is radish.

Napiform : The base region of the root is swollen becoming almost spherical in shape, and then it

abruptly tapers towards the lower end, forming a tail-like structure. Example of Napiform roots are turnip

and beet.

Conical: In the conical form of root modification the roots are swollen and are broad at the base, the apex

part gradually tapers forming a con like structure like in carrot.

Tuberous or tubercular : In the case of tuberous roots, the roots are thick and fleshy. They do not form

any definite shape. Example: Sweet potato, yam.

Pneumatophores : The pneumatophore roots grow vertically up, they protrude out of water or marshy sol

like conical spikes. These roots occur in large number around the trunk of the tree. Pneumatophore roots

are many pores for breathing through which exchange of gases takes place for respiration. Example of

pneumatophores are Rhizophora.

Adventitious Root Modifications Back to Top

Adventitious roots are the roots that are produced from any portion of the plant other than the radicle. The

root system may be changed to different forms for special functions like storage, mechanical support and

vital functions.

A. For Storage Of Food

Tuberous root : The adventitious roots in this are grown from the nodes of the running stem. These roots are

modified are swollen into irregular forms and are known as tuberous roots. They are produced in single

number. Example: Sweet Potato.

Parts of a stem These are the basic elements of a plant stem and the organs (eg leaves and flowers) which extend from

it:

This is the role of each of the major stem parts:

Stem The term ’stem’ refers to the structure which provides support for the plant and connects the roots (which

draw up water and nutrients) to the leaves (which produce energy) and flowers (which are in charge of

reproduction). There can be one stem originating from the roots with lateral stems growing from it, many

different stems coming out from the roots, or a combination of the two. Where there is just one stem

coming from the roots of a woody perennial this is known as a ‘trunk’.

Branch/lateral growth/side shoot These different terms are all used to describe stems which come out of the main stem. Generally this

growth is slightly slimmer than the main stem or ‘trunk’ of the plant.

Node Nodes are areas of growth. These parts of the stem contain a lot of cells which are called ‘meristematic‘;

cells which actively divide to create lots of new cells. Nodes are where you will find buds, side shoots,

leaves and flowers growing. Nodes are important when propagating plants by stem cuttings.

Internode This is the space between two nodes. It is the area which extends to give the stem more length and,

therefore, the plant more height. It is also known as the ‘internodal’ area.

Axillary bud These are buds which form in the axils between a stem and a side shoot, or between a stem and a leaf.

These buds may remain dormant or may develop into a side shoot, leaf or flower.

Apical bud This type of bud is found at the tip of stems and denotes a strongly meristematic area, ie an area where

cells are actively dividing and, therefore, lengthening the stem. At these apical growth points there is a

build up of a hormone called auxin, which controls the growth. The heightened levels of auxin at the tips

of stems inhibits the axillary buds (this is called ‘apical dominance’) and is the reason why they often

remain dormant. When we prune plants we remove the apical buds, which encourages more growth from

the axillary buds. This is why plants often become more bushy with pruning .

Leaf The leaves are either sessile (growing directly out of the stem) or petiolate (growing on a stalk called a

petiole). Leaves grow out of nodes and the point where the leaf or petiole meets the stem is called the

leaf axil.

Pedicel and flower See ‘parts of a flower‘.

The internal structure of a stem varies depending on the type of plant. Its basic constituents are the

phloem and xylem vessels which form the plant’s transportation system, meristematic ‘cambium’ cells

which are actively dividing cells producing more phloem and xylem tissue, and cortex cells which fill in the

gaps between the other types of cells and can also store food or become meristematic (growing) in order

to repair damage to the stem.

In woody perennials, and some other plants, the ongoing production of phloem and xylem cells is

responsible for the thickening of the plant’s stems. This increase in width stretches and squashes the

epidermis, or ’skin’, of the stem, so the plant has to keep on producing new epidermal cells. The old, dead

cells build up and appear as bark on the outside of the stem. Tiny pores (which appear as spots on some

stems) called ‘lenticels’ allow gases (such as oxygen) to enter and leave the inside of the stem, used for

purposes such as respiration.

Stems can also be modified into many different forms, including:

Fasciculate root : The tuberous roots are developed from the base of the stem in cluster. Nodulose root :

The adventitious roots in this case arise from the underground stem. Some roots that are

slender become swollen near the apex and they form nodule like structures. Example: mango-ginger.

Moniliform or Beaded roots : In this case, the roots are swollen at frequent intervals. This formation gives a

beaded or moniliform type of appearance. This form of root formations is seen in many grasses, Basella, etc.

Annulated roots : This type of roots has ring-like swellings ina series and appears in the form of a number of

discs placed one above the other. Examples are Cephalis ipecacuanha (Ipeca).

B. For Mechanical Support

Prop roots : Here the plants have tap roots system. the horizontal branches of the stem of the plant gives rise

to aerial roots. These aerial roots hang vertically downwards. These roots on reaching the ground, they grow

and act like pillars. They provide mechanical support to the plant. Example Ficus bengalensis.

Stilt Roots : These plants have their own roots system like in screwpine. They are not strongly anchored tothe

soil. Hence, these plant develop adventitious roots from near the base of the stem. These roots grow obliquely

downwards. They act like stilt and they provide mechanical support to the plant. Example - the maize plant

produces adventitious roots form the lower nodes which also act in a similar way.

Climbing roots : This type of root system is found in climbers. Adventitious roots are developed from the

nodes and are aerial roots. These aerial roots twist and clasp the support and help in climbing. Example Betel,

Pothos, etc.

Clinging roots : This type of roots are seen in orchids. These roots arise from the stem base of the plant. They

enter crevices of the support to fix the epiphyte. They provide the plant with mechanical support.

Root buttresses : Some trees have great plant-like roots that radiate from the base of the stem of the tree. It

consists of partly root and partly stem. Example is Bombax.

C. For Vital Functions

Sucking roots or Haustoria : Cuscuta is a leafless, parasitic plant, it always grows in association with other

plants. The parasatic plant at the point of attachment with the host plant produces some knob like roots known

as haustoria which penetrate into the host plant and draws nourishment.

Epiphytic roots : are the plants like orchids that grow perched on tree branches. They attach themselves

firmly to the trunk of the tree by the aid of social roots known as climbing roots.

They also have aerial roots for absorbtion. These roots are fleshy and remain along with the clinging roots.

These roots have spongy tissues which absorb moisture from the atmosphere. They also have chlorophyll

pigment and photosynthesis takes place.

Floating roots: are found in aquatic plants. These roots develop from the nodes of the floating branches. The

roots are spongy and are colorless. These roots are present above the level of water. As these roots are

spongy and soft, they store air in them which help the plant in floating. They also help in respiration process.

Assimilatory roots : are normally non-green in color. The adventitious roots are developed from the branches

of the plant Tinospora cord folia. These branches are green in color and carry out photosynthesis, the roots

developed from this are known as assimilatory roots. The assimilatory roots are slender, long and in hanging

state.

Modification of Stems

The stem shows different modifications like root to perform some special functions like synthesizing the food materials, conducting water and mineral salts to the leaves, poliage to sunlight for photosynthesis etc., Depending on their nature they are of 3 typesas follows

Underground stem modification

Generally stems are present above the soil (aerial) but in some plants they grow below the soil which are called as underground or subterranean or geophyllous stems or stem modifications. They will store food materials and the well protected from herbivorous animals, by performing these functions they are also known asmultipurpose stem modifications.

These stems contains nodes, internodes, scale leaves axillary and terminal buds. Based on their growth and the storage of food materials they are of 4 types as follows:

Rhizome

It is the thickest underground stem which grows horizontally below the soil consisting of nodes and

internodes.

It is brown in colour and dorsiventral producing aerial branches and reproductive organs on the dorsal side and adventitious roots on the ventral side.

The nodes consists of scale leaves and branches arises from axillary buds (to store the food materials and maintains the horizontal growth) and the aerial branches of rhizome are called as scapes.

The vertical rhizome of this is known as root stock.

Examples: Ginger, Turmeric

Corm

The stem which grows vertically in the soil at a particular depth consisting of nodes and internodes.

The food materials are synthesized in aerial branches and stored by the stem. Hence it becomes tuberous.

Leaves are reduced to scale leaves and the axillary buds produced daughter corms and it consists of some

special roots are called as pull roots or contractile roots.

Example: Amorphophyllus, Colacasia

Stem tuber

In this, branches develops from the lower part of the stem and grows into the soil, the apices of these

branches stores food materials hence they will become tuberous which are known as stem tubers and can grow at any depth.

This is covered by a brown coloured layer periderm which bears many eyelike structures represents the nodes.

Each eye possesses a semi-lunar leaf scar which represents the position of scale leaf and also helps in

vegetative propagation.

The vegetative propagation through eyes is called sprouting.

Example: Potato, Helianthus

Bulb

It is a special type of underground stem which is reduce to biconvex dislike structure with number of

adventitious roots on its lower side and does not stores the food.

The leaves develop on the upper side of the disk and grow above the soil.

The leaf bases stores the food and water hence they will be fleshy.

The axillary buds produce daughter bulb and terminal bud is at the centre and develops aerial shoots producing inflorescence.

Depending on arrangement of scale leaves they are of two types as follows:

o Tunicated bulb: In this the leaf bases of scale leaves overlap one above the other in a

concentric circles and the entire bulb is covered by dry, membranous scale leaves called as tunica.

Example: Onion

o Scaly bulb or naked bulb or imbricate bulb: The scale leaves are fleshy which are loosely

arranged are called as cloves. It the leaf is covered by tunica and the bulb is not covered

with that, called as naked bulb. It the scale leaves are arranged in a group with shinning tunica, called as imbricate bulb. If the stem and leaf bases stores the food materials they appear in the form of solid bulbs.

Example: Tuberose, cloves ,Lilium

Sub-aerial stem modifications:

The stem which grows partly aerial and partly below the soil are called as sub-aerial stems which are specialized for vegetative propagation. They are of four typesas follows

Runners

In this, the stem creeps on the soil and the rooted at every node.

When the internodes break of nodes leads an independent life, such stems are known as runners which help in vegetative propagation.

Examples: Hydrocotyle, Oxalis

Stolons or walking stems

In this the slender branches arises from the base of the stem which grows obliquely downwards.

When these branches touch the soil they produce adventitious roots, called as stolons. It separated from the mother plant they leads an independent life.

Examples: Jasmine, Nerium

Suckers

In this underground branches grows obliquely upwards from the axillary buds of nodes present below the soil.

These branches produce adventitious roots on the ventral surface, called as suckers. If separated they leads an independent life.

Examples:Mentha,Chrysanthemum

Offsets

Stem is reduced to a disc like structure and the leaves from this grows in rosette manner.

The axillary buds of these leave develop into short and the slender branches of one Internodal length and grows horizontally above the water, called as offsets.

The apex of each set bears number of leaves on the upper side and the adventitious roots on its lower, if it breaks they leads an independent life.

Example: Pistia, Lemna

Aerial stem modifications

The stem which grows aerially consisting of vegetative parts a floral parts of plants growing in different environmental conditions and undergo modifications to perform various function are called as aerial stem modifications. They are of 6 typesare as follows

Tendrils

Some weak stemmed plants produce wiry, coiled and sensitive structures for the purpose of climbing, called as tendrils. They coil around the support and helps in climbing formed from the axillary or terminal buds.

Examples: Passiflora, Vitis vinifera

Thorns

These are hard, woody pointed structures which meant for protection develops either from axillary bud or terminal bud.

Examples: Duranta, Carissa

Hooks

These are woody, curved sensitive structure developed either from axillary or terminal bud.

Examples: Hugonia, Artobotrys

Phylloclades

In these plants leaves are modified into scale leaves or spines and man stem branches modifies into green leaf like structures to perform photosynthesis known asphylloclades or cladophylls.

Phylloclades which contains only one internode known as cladode.

Examples: Asparagus, Opuntia, casuarina

Tuberous stem

The aerial stem of the plants stores food materials and become tuberous known as tuberous stem.

Examples: Brassica, Bulbophyllum

Bulbils

`The plants consisting of vegetative and floral parts modified into condensed branches which stores food materials, these modified buds are known as bulbils.

Examples: Diascorea, Oxalis

The Parts of a Leaf

Most leaves have two main parts: (1) the blade and (2) the

petiole, or leafstalk. The leaves of some kinds of plants also

have a third part, called the stipules.

The Blade, or lamina, is the broad, flat part of the leaf. Photosynthesis

occurs in the blade, which has many green food-making cells. Leaf

blades differ from one another in several ways: (1) the types of edges, (2)

the patterns of the veins, and (3) the number of blades per leaf.

The Types of Edges. Almost all narrow, grasslike leaves and needles

leaves have a blade with a smooth edge, as do many broadleaf plants,

particularly those that are native to warm climates. The rubber plant, a

common house plant, is a good example of such a plant.

The leaves of many temperate broadleaf plants have small, jagged points

called teeth along the blade edge. Birch and elm trees have such leaves.

Some plants have hydathodes, tiny valvelike structures that can release

excess water from the leaf. The teeth of young leaves on many plants,

including cottonwood and pin cherry trees, bear tiny glads. These glands

produce liquids that protect the young leaf from plant-eating insects.

Some temperate broadleaf plants -- including sassafras trees and certain

mulberry and oak trees -- have lobed leaves. The edge of such a leaf

looks as if large bites have been taken out of it. This lobing helps heat

escape from the

leaf.

The Patterns of

the Veins. Veins

carry food and

water in a leaf.

They also support

the blade, much as the metal ribs support

the fabric of an open umbrella.

In most broad leaves, the veins form a

netlike pattern, with several large veins

connected by smaller ones. The smallest

veins supply every part of the blade with

water. They also collect the food made by the green cells.

There are two main types of net-vein patterns -- pinnate (featherlike) and palmate (palmlike or

handlike). Pinnately veined leaves have one large central vein, called the midrib, which extends

from the base of the blade to its tip. Other large veins branch off on each side of the midrib. The

leaves of beech, birch, and elm trees have such a vein pattern. A palmately veined leaf has

several main veins of about equal size, all of which extend from a common point at the base of

the blade. The vein patterns of maple, sweet gum, and sycamore leaves are palmate.

Narrow leaves and needle leaves are not net-veined. Narrow leaves have a parallel-vein pattern.

Several large veins run alongside one another from the base of the blade to the tip. Small

crossveins connect the large veins. Needle leaves are so small that they have only one or two

veins running through the center of the blade.

The Number of

Blades per Leaf. A

leaf with only one

blade is called

a simple leaf.

Apple and oak

trees, grasses, and

many other plants

have simple

leaves. A leaf with

more than one

blade is known as

a compound leaf.

The blades of a

compound leaf are

called leaflets.

The leaflets in a

compound leaf

may be arranged

in a pinnate or

palmate pattern. In pinnately compound leaves, the leaflets grow in two rows, one on each side

of a central stalk, called the rachis. Plants with pinnately compound leaves include ash and

walnut trees and garden peas. The leaflets in a palmately compound leaf all grow from the tip of

the leafstalk. Clover, horse chestnut trees, and many other plants have palmately compound

leaves.

A few plants -- including carrots, honey locust trees, and Kentucky coffeetrees -- have double

compound leaves, with each leaflet being divided into a number of still smaller leaflets.One

double compound leaf looks more like a group of twigs and leaves than like a single leaf.

The Petiole is the stemlike part of the leaf that joins the blade to the stem. Within a petiole are

tiny tubes that connect with the veins in the blade. Some of the tubes carry water into the leaf.

Others carry away food that the leaf has made. In many trees and shrubs, the petioles bend in

such a way that the blades receive the most sunlight, thus assuring that few leaves are shaded by

other leaves. The petiole also provides a flexible "handle" that enables the blade to twist in the

wind and so avoid damage.

In some plants, the petioles are much larger than the stems to which they are attached. For

example, the parts we eat of celery and rhubarb plants are petioles. In contrast, the leaves of

some soft-stemmed plants, particularly grasses, have no petioles.

The Stipules are two small flaps that grow at the base of the petiole of some plants. In some

plants, the stipules grow quickly, enclosing and protecting the young blade as it develops. Some

stipules, such as those of willows and certain cherry trees, produce substances that prevent

insects from attacking the developing leaf.

In many plants the stipules drop off after the blade has developed, but garden peas and a few

other kinds of plants have large stipules that serve as an extra food-producing part of the leaf.

Leaf venation

Illustrations by Marina Smelik

Leaf venation refers to the pattern of veins on the leaf. The veins supply the leaf with

water and minerals from the roots and transport materials from the leaf to the rest of

the plant. The vein pattern can be useful for plant identification when the pattern is

distinct and obvious, so only a few basic patterns will be used in this course.

LEAF VENATION PATTERNS

The primary vein is like the trunk on a tree. It is the widest vein on the leaf and starts

at the base of the leaf.

Secondary veins are like the main branches on a tree, they are smaller than the

primary vein.

There are two ways the secondaries may come off the primary. In one pattern,

illustrated on the left below, the secondaries come off of the primary vein all along the

length of the primary. In the second pattern, illustrated on the right below, secondaries

originate from at or near the base of the primary.

Leaf secondary veins all arising along entire length of primary vein.

Leaf secondary veins (at least some) arising at or near leaf base.

Secondary veins parallel to each other for their entire length, stay straight all the way

to the leaf margin.

Secondary veins parallel to each other for their entire length, curve upward as they

approach the leaf margin.

Leaf secondary veins not parallel to each other for their entire length, secondary

veins much-branched.

What's the Difference Between

Monocot & Dicot Leaves?

Traditionally all members of the class of

flowering plants have been regarded as

belonging to one of two subclasses: They were

either monocots or dicots. In our flower section

we have a special pageshowing differences

between monocot and dicot flowers, plus we

have another pageindicating that nowadays all

flowering plants aren't necessarily considered

either monocots or dicots.

Still, for our backyard purposes, thinking in

terms of monocots and dicots can be very

useful. For example, look at the big differences

distinguishing the leaves of most monocots and

dicots:

Dicots include nearly all our trees, bushes, vegetable-garden plants (not corn),

and most of our wildflowers (not irises and lilies). Dicot leaves are

usually net-veined, as in the close-up of the veins in a wild grape leaf at the

right. Notice how the larger veins are thicker and straighter, but as veins get

smaller and smaller, they tend to snake

around.

Monocots include all grasses and glasslike

plants, plus lilies, irises, amaryllises, and some

other plant types. Usually, but not always,

monocots possess parallel-veined leaves, as

typified in the simple blade of fescue grass

shown at the right. One example of a monocot

which does not have parallel-veined leaves is

the Trillium, several species of which are

common in moist American forests.

Leaf Attachments and Arrangements

leaf attachment

node - the point of leaf attachment to a stem.

internode - the region of the stem between leaves.

petiolate - a leaf attached to the stem by a petiole.

sessile - a leaf whose blade is attached directly to the stem, lacking a petiole.

clasping (or amplexicaul) - a sessile leaf with free bases partly or entirely surrounding the stem.

sheathing - with a tubular portion of the leaf blade surrounding the stem below the base.

decurrent - with leaf blade extended downward along the stem, forming vertical lines along the

stem.

ochreate - with stipules forming a thin tube around the stem above petiole.

perfoliate - with the bases of a single leaf fused around the stem, which appear to go through the

leaf blade.

connate-perfoliate - with bases of opposite leaves fused around the stem, which appear to go

through the leaf.

leaf arrangement

phyllotaxy - the arrangement of leaves on an axis.

2-ranked - arranged in 2 rows, one on either side of the stem or central axis.

alternate - an arrangement with 1 leaf attached at each node.

distichous - 2-ranked, with alternate leaves arranged on opposite sides of a stem, not spirally

arranged.

equitant - 2-ranked basal leaves, folded and flattened in the same plane, and with alternately

overlapping bases. New leaves emerge between the bases of the previous leaf, e.g.,

characteristic of irises (Iridaceae), Tofieldia (Tofieldiaceae), and Zingiberales.

opposite - an arrangement with 2 leaves attached at each node, on opposite sides of the stem.

decussate - with opposite leaves attached at right angles to the adjacent pairs of leaves.

whorled - an arrangement with 3 or > leaves attached at each node.

imbricate - with overlapping bases, the previous layer of leaves or scales overlapping younger

layers.

fascicle - 2 or > leaves grouped in a bundle and bound together at the base, derived from a

reduced shoot.

basal leaves - leaves arranged around the base of a stem.

rosette - a group of basal leaves.

cauline (or radical) leaves - leaves arranged along an aerial stem.

Leaf Apices

vernation - the arrangement of leaves in a bud.

circinate - a coiled vernation, with the frond apex in the centre of the coil; produced the

distinctive fiddlehead-shaped young leaves in ferns.

arrangement of stomates (pores in leaf epidermis, surrounded by guard cells and subsidiary

cells).

anomocytic - with no specialized subsidiary cells.

paracytic - with 2 specialized subsidiary cells surrounding the guard cells.

paratetracytic - with 4 specialized subsidiary cells surrounding the guard cells.

pericytic - with 1 specialized subsidiary cell surrounding the guard cells.

amphiparacytic - with 2 rows of 2 subsidiary cells surrounding the guard cells.

Attenuate a sharp-pointed apex with concave margins that form an angle less than (<) 45

degrees.

Acuminate a sharp-pointed apex with straight or convex margins that form an angle less than

(<) 45 degrees.

Acute an pointed apex with margins that form an angle between 45 and 90 degrees.

Obtuse a blunt apex with margins that form an angle greater than (>) 90 degrees.

Rounded an curved apex with margins that form a smooth arc.

Leaf Margin

LEAF MARGINS

The margin of a leaf is another name for the structure of the

leaf's edge.

There are many different variations, and they can be discovered

in this tutorial.

Caudate an attenuate apex with a slender tail-like appendage at the tip.

Cuspidate an acute apex with a stiff tip or cusp.

Mucronate with a small extension of the midrib barely extending beyond the blade apex.

Emarginate with a shallow depression at the apex, not exceeding ? of the distance to the centre

of the leaf blade.

Truncate a broad, flat apex, abruptly ending at right angles to the midvein.

Retuse a rounded summit with a shallow depression at the apex, not exceeding 1/16 of the

distance to the centre of the leaf blade.

Obcordate apex with prominent, rounded lobes, cut ? to ¼ of the distance to the centre of the

leaf blade.

Cleft apex divided into rounded or straight-margined lobes, cut ¼ to ½ of the distance to

the centre of the leaf blade.

Entire

A leaf that is smooth all the way around has an Entire margin

Crenate

If a leaf has a Crenate margin, then the edge of the leaf has blunt, rounded teeth.

Dentate

A Dentate margin is when a leaf has triangular, "tooth-like" edges.

Serrate

A Serrate margin is when a leaf has sharp, "saw-like" teeth.

An easy way to remember this margin is to picture this leaf as a similar to a serrated knife.

Doubly-Serrate

When a leaf is Doubly-Serrated, the "saw-like" teeth have even smaller teeth.

Mid-Margin Quiz

A quiz will load up below. If you find that you are not scoring very high, be sure to go back and review.

Serrulate

A leaf with a Serrulate margin is similar to Serrate, but has smaller, evenly-spaced teeth.

Incised

If a leaf has an Incised margin, it has deep, irregular teeth.

Lobed

When a leaf has a Lobed margin, the leaf has deep, rounded edges.

Sinuate

A Sinuate margin describes the sinuous, slighly wavy line along the edge of a leaf.

Undulate

When a leaf has an Undulate margin, it has extremely wavy lines along the edge.

Leaf Bases Attenuate

Leaf blade gradually tapers to a narrow base.

Cuneate

Leaf blade tapers to a narrow wedge-shaped base.

Acute

Leaf blade tapers to a sharp triangular-shaped base.

Cordate

Heart-shaped blade with a gently lobed base.

Rounded

Leaf blade has a rounded base.

Oblique

Each side of the leaf blade attaches at a different point on the petiole.

Truncate

Leaf blade is square at the base.

Auriculate

Leaf blade has lobes resembling ears.

Hastate

An arrow-shaped leaf with lobes that taper away from the petiole.

Sagittate

An arrow-shaped leaf with lobes that taper downward.

Leaf shape

Chart illustrating leaf morphology terms

Oddly pinnate, pinnatifid leaves (Apium graveolens, Celery)

Perfoliate bracts completely surrounding the plant stem (Lonicera sempervirens)

Simple, palmate-veined leaves

A single laciniate leaf ofAdenanthos sericeus

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

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

Acuminate (acuminata): Tapering to a long point

Acute: pointed, having a short sharp apex angled less than 90°

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

Asymmetrical: With the blade shape different on each side of the midrib

Basal: arising from the crown, bulb, rhizome or corm, etc. as opposed to cauline

Bipinnate (bipinnata): Each leaflet also pinnate

Caudate: tailed at the apex

Cauline: borne on the stem as opposed to basal

Compound: Not simple; the leaf is broken up into separate leaflets, and the leaf blade is not continuous

Cordate (cordata): Heart-shaped, with the petiole or stem attached to the 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

Entire: having a smooth margin without notches or indentations

Falcate (falcata): Sickle-shaped

Fenestrate (fenestrata) "windowed" with holes (e.g. Monstera deliciosa or Aponogeton fenestralis), or window-like patches of translucent tissue. (cf Perforate)

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

Laciniate: Very deeply lobed, the lobes being very drawn out, often making the leaf look somewhat like a branch or a pitchfork

Laminar: Flat (like most leaves)

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

Linear (linearis): Long and very narrow

Lobed (lobata): With several points

Mucronate: Ending abruptly in a sharp point[1]

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[2] or lobes[3] radiating from the base of the leaf.

Pedate (pedata): Palmate, with cleft lobes[4]

Pedatifid (pedatifida)[5]

Peltate (peltata): Rounded, stem underneath

Perfoliate (perfoliata): Stem through the leaves

Perforate (perforata): marked with patches of translucent tissue, as in Crassula perforata and Hypericum perforatum, or perforated with holes (cf "Fenestrate")

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)

Serenoa repens showing pleated elliptic leaves of seedling and pleated palmate leaves of mature plant

Plicate (plicatus, plicata): folded into pleats, usually lengthwise, serving the function of stiffening a large leaf.

Pungent (spinose): Having hard, sharp points.

Reniform (reniformis): Kidney-shaped

Retuse: With a shallow notch in a broad apex

Rhomboid (rhomboidalis): Diamond-shaped

Round (rotundifolia): Circular

Sagittate (sagittata): Arrowhead-shaped

Simple: Leaf blade in one continuous section, not divided into leaflets (not compound)

Spear-shaped: see Hastate.

Spatulate, spathulate (spathulata): Spoon-shaped

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

Subobtuse (subobtusa): Somewhat blunted, neither blunt nor sharp

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

Undulate (undulatus): wave like

Unifoliate (unifoliata): With a single leaf