So that leafy plants can be better identified, their leaf shapes are divided into different categories. In addition to the shape, it is also important to determine how and where the leaves are on the stem.

In a nutshell

  • the leaf shape is mostly symmetrical
  • there are divided and undivided leaves
  • the leaf tip and leaf edges are also important for identifying a plant
  • the function is the same for almost all leaf shapes
  • the cotyledon or cotyledons often deviate from the actual leaf shape

General Shapes

This classification describes the outer leaf shape of the entire single leaf without considering the tip or the edges. It is important that leaves cannot be pressed into generally valid forms, so these are only approximate figures. Each individual plant usually has leaves of different shapes and sizes. With a few exceptions, the only function of the leaves is photosynthesis, i.e. plant respiration. In the case of poisonous plants such as ivy, the leaves also have a protective function.

ruler

The leaves are long and thin, with little bulging on the sides. Sometimes they are a little thicker and thus resemble needles.
Examples: Field horsetail, lavender, meadow bedstraw, sea buckthorn

lanceolate

If the leaf shape is lanceolate, the leaves are longer than they are wide. The leaf blade is widest in the middle of the leaf, and the tip of the leaf often tapers to a point.
Examples: Plantain, some willow species

Notice: Almost all types of grass have linear or lanceolate leaves, the large leaves of the maize plants are particularly striking. The exact distinction between lanceolate and linear is not easy.

egg shaped

This leaf shape resembles an egg and, like this, has its widest point below the middle. The upper end is more pointed than the lower one.
Examples: some poplar species, cherry (obovate)

Elliptical

The difference between the elliptical and the ovoid leaf shape is that the widest point in the elliptical leaf shape is roughly in the middle of the leaf. In addition, both ends of the leaf are flattened.
Examples: some willow species, beech species, boxwood

plump

Rounded leaves are either perfectly round or almost round. There is usually an indentation on the stem. Length and width are similar.
Examples: some poplars, alder, pennywort

shield shaped

In the case of shield-shaped leaves, the stalk is attached to the underside of the leaf approximately in the middle or slightly below the middle. The leaf veins radiate out from the base of the stem. In some plants, shield-shaped leaves have the function of floating leaves.
Examples: Nasturtium, Pennywort

heart shaped

The leaf has a pointed heart shape. The widest point is below the middle, the leaf is bulged to the right and left of the base of the stem. There are also leaves that are inverted heart-shaped.
Examples: Linden, convolvulus

kidney shaped

The leaf has the typical shape of a kidney. It is wider than it is tall, and there are two deeply cut arches next to the base of the handle.
Example: violet

wedge shaped

The leaves are approximately triangular, the widest point is usually on the stem. If the leaf shape is oblique, the widest point is at the tip of the leaf.
Examples: Black poplar, some birches

compound leaves

Composite sheets basically consist of several individual sheets. These have the leaf shapes mentioned above. The leaves are mostly lanceolate.

Imparipinnate

Often there are seven or five individual leaves, two of which are placed opposite each other as a pair, with a single leaf sitting at the top.
Examples: Walnut, blackberry, rose species, ash

Pair pinnate

In the case of pinnate leaves, the individual leaves are also found in pairs on the petiole. However, it is an even number and there is no single leaf at the top.
Examples: some species of peas or vetches

Doubly pinnate

In the case of bipinnate leaves, the single leaves are also divided into individual leaves.
Examples: Yarrow, dyer's chamomile, ferns (here the leaves have the function of reproduction, since the spores are on the underside)

Feathered unevenly

With this leaf shape, the leaves are divided into individual leaves, which are located irregularly on the stem. The leaves are usually of different sizes.
Example: Maple-ash or ash-maple

Fingered in threes (four or more)

The leaf consists of three individual leaves that are regularly arranged.
Example: The typical representative is the clover. Most types of clover have threefold fingered leaves, with rarely more than three single leaves occurring (4 single leaves are the rule for lucky clover).

Fingered fivefold

The sheet consisted of at least five, sometimes up to seven individual sheets. The leaf usually appears palmate.
Examples: Chestnut, monkshood

Classification based on the tip of the leaf

So that a plant can be identified correctly, the tip of the leaf can also be examined in addition to the leaf shape. Sometimes the assignment is not clear, since there can be different leaf tips on one plant species.

pointed

The leaves taper to a point. One of the most common leaf shapes.
Examples: very many trees and grasses with lanceolate leaves, blueberries (ovoid-pointed)

blunt

The tip of the leaf is slightly flattened.
Examples: willow species, magnolia

Notice: The distinction between blunt and pointed can be difficult, for example, in the case of the service pear, both occur.

Rounded

The leaf tip is clearly flattened or rounded. This form occurs with rounded and shield-shaped, but also with kidney-shaped leaves.
Examples: violet, water lily

marginalized

There is a small, shallow indentation at the rounded tip of the blade.
Examples: some clovers

Classification based on the edge of the sheet

Most leaves have a smooth edge, but can also be wavy or more or less strongly indented. Depending on how strong this indentation is, the leaf shapes are classified as follows:

entire

The sheet margin is unbroken and not indented. It runs in a continuous line around the entire sheet.
Examples: most fruit trees (except cherry), privet

sawn

The edge of the blade has a saw blade-like structure, it is important to distinguish it from serrated blades. Sawn leaves have both sharp interior angles and sharp "teeth".
Examples: Midsummer Spurge, Nettle

Double sawn

The teeth are sawn again, so small and large saw teeth alternate on the leaves.
Examples: Birch species, beeches, hazel

Serrated

In the case of serrated leaves, the inner angles are blunt. Otherwise they resemble sawn leaves.
Examples: Rowan, Maple, Holly, Garlic Mustet, Dandelion (also known as Scrap Saw)

Notice: Sawn or toothed leaves not only have the usual function, they are also supposed to ward off predators. This is especially true if they also have thorns or spikes.

notched

The leaf margin is regularly notched. The outer edge is round, while the notch is pointed.
Examples: some speedwell species, ground ivy, dead nettle

booked

Indented leaves have more or less strong indentations that are rounded. A typical representative is the acorn.
Further examples: Coltsfoot, thistles (with thorns, leaves have a defensive function)

Lobed

Lobed leaves have very deep incisions that usually divide the leaves into three, sometimes five sections.
Examples: Maple, currants, gooseberries, ivy

pinnate

Even cuts that are not too deep divide the leaves into sections.
Examples: Horseradish, silver thistle, Norway maple, but also gingko

pinnate

The incisions reach almost to the leaf blade and seem to divide the leaf into several individual leaves.
Examples: Celandine, cranesbill, thistles

frequently asked Questions

Do different leaf shapes occur on one plant?

Most of the time, basal leaves, which emerge from the plant just above the ground, are distinct from the leaves that grow higher up from the stems. Leaves related to the flowers can also look different.

Are there typical leaf shapes for trees, shrubs or herbaceous plants?

No, there is no leaf shape that would be characteristic of a plant type.

How are leaves classified?

The base of the leaf, on which any stipules are located, is attached directly to the stem. This is followed by the petiole, which extends to the tip of the leaf. The sides of the leaves are called leaf blades. The individual leaf veins emerge from the petiole.

How can a leaf be attached to the stem?

The leaf can be stalked, attached with or without stipules or a leaf sheath, or it can be sessile on the shoot. It can also encircle or run down the stem.

How does the position of the leaves differ on the plant?

There are alternate leaves that grow alternately along the shoot axis, the leaves are never at the same height. In the case of opposite growth, on the other hand, there are always two leaves at the same height opposite each other. Whorled leaves grow around the entire stem at the respective leaf node. There are also rosette plants in which the leaves emerge either directly from the ground or from a short shoot all in the same place.

Category:

Indoor plants