What is the plant order Asterales?

Asterales is an order of flowering plants characterized by shared chemical traits like the presence of ellagic acid and inulin, as well as morphological similarities such as plunger pollination. This order contains 11 families and roughly 26,870 species. The major families within Asterales are Asteraceae and Campanulaceae. The remaining families, which have far fewer species, are Goodeniaceae, Stylidiaceae, Menyanthaceae, Calyceraceae, Rousseaceae, Pentaphragmataceae, Alseuosmiaceae, Phellinaceae, and Argophyllaceae. The Asteraceae family, also known as the daisy family, is a large family of flowering plants, with more than 1,620 genera and 23,600 species.

Which common types of plants are found in Asterales?

The Asterales order of flowering plants contains 11 families and roughly 26,870 species. This order is part of the core asterid clade in the euasterid II group of the Angiosperm Phylogeny Group III (APG III) botanical classification system. Common types of plants found in Asterales: * Ageratums, asters, chrysanthemums, cosmos, dahlias, marigolds, and zinnias are examples of garden ornamentals. * Asteraceae includes food crops such as artichokes, lettuce, endive, and salsify. * The bellflower family ( Campanulaceae ) are mainly garden ornamentals.

What are some unique features of Asterales plants?

The Asterales order, also known as the daisy order, contains 11 families and roughly 26,870 species. Plants in the Asterales order have unique traits, such as the presence of ellagic acid and inulin, along with a specialized plunger pollination mechanism. The Asteraceae family, a major family within Asterales, has flower heads that resemble individual flowers. These heads are composed of many small flowers, called florets, surrounded by bracts. What appear to be the petals of a daisy or sunflower are actually the outermost flowers of the head. The sepals are reduced to a ring of hairs, scales, or bristles called the pappus on the mature fruit. The one-seeded fruit is an achene with a hard outer covering.

How are the flowers of Asterales plants usually arranged?

Plants in the order Asterales, which includes the Asteraceae (daisy) family, are characterized by their unique flower arrangements. The flowers are grouped into compact inflorescences or heads that resemble single flowers. These heads are typically surrounded by an involucre of small, modified leaves called bracts. An inflorescence in this family can consist of over 1,000 individual flowers (also known as florets), and the heads themselves can be grouped into more complex arrangements called capitulescences. The flowers in the outermost rows often have a modified, flat, and elongated corolla that looks like a petal of a regular flower.

Where can you commonly find plants from the Asterales order around the world?

The Asteraceae family, also known as the aster, daisy, or composite family, is within the order Asterales. It contains over 1,620 genera and 25,000 species of herbs, shrubs, and trees distributed throughout the world. The order Asterales has 11 families and about 26,870 species. Paleobotanists believe the first members of this family evolved in Argentina around 50 million years ago.

Why is the Asterales order important to humans and the environment?

The Asterales order, containing around 26,870 species across 11 families, significantly impacts humans and the environment. Many species are cultivated as garden ornamentals, such as asters , chrysanthemums , and marigolds . Economically important food crops include artichokes , lettuce , endive , sunflower , and safflower , the seeds of which are used to produce cooking oils. Some Asterales, like wormwood, are sources of poisonous oils. Certain species, such as marigolds, release compounds that kill plant-parasitic nematodes in the soil. However, some members, including ragweed and thistle, are troublesome weeds; ragweed is a significant allergen.

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Annual blanketflower (Gaillardia pulchella).

giant ragweed, a common cause of hay fever

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Top Questions

What is the plant order Asterales?
Asterales is an order of flowering plants characterized by shared chemical traits like the presence of ellagic acid and inulin, as well as morphological similarities such as plunger pollination. This order contains 11 families and roughly 26,870 species.

The major families within Asterales are Asteraceae and Campanulaceae. The remaining families, which have far fewer species, are Goodeniaceae, Stylidiaceae, Menyanthaceae, Calyceraceae, Rousseaceae, Pentaphragmataceae, Alseuosmiaceae, Phellinaceae, and Argophyllaceae. The Asteraceae family, also known as the daisy family, is a large family of flowering plants, with more than 1,620 genera and 23,600 species.
2 Britannica Sources
1. Definition of Asterales
2. Asterales
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Which common types of plants are found in Asterales?
The Asterales order of flowering plants contains 11 families and roughly 26,870 species. This order is part of the core asterid clade in the euasterid II group of the Angiosperm Phylogeny Group III (APG III) botanical classification system.

Common types of plants found in Asterales:
* Ageratums, asters, chrysanthemums, cosmos, dahlias, marigolds, and zinnias are examples of garden ornamentals.
* Asteraceae includes food crops such as artichokes, lettuce, endive, and salsify.
* The bellflower family (Campanulaceae) are mainly garden ornamentals.
4 Britannica Sources
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What are some unique features of Asterales plants?
The Asterales order, also known as the daisy order, contains 11 families and roughly 26,870 species. Plants in the Asterales order have unique traits, such as the presence of ellagic acid and inulin, along with a specialized plunger pollination mechanism.

The Asteraceae family, a major family within Asterales, has flower heads that resemble individual flowers. These heads are composed of many small flowers, called florets, surrounded by bracts. What appear to be the petals of a daisy or sunflower are actually the outermost flowers of the head. The sepals are reduced to a ring of hairs, scales, or bristles called the pappus on the mature fruit. The one-seeded fruit is an achene with a hard outer covering.
3 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
How are the flowers of Asterales plants usually arranged?
Plants in the order Asterales, which includes the Asteraceae (daisy) family, are characterized by their unique flower arrangements. The flowers are grouped into compact inflorescences or heads that resemble single flowers. These heads are typically surrounded by an involucre of small, modified leaves called bracts.

An inflorescence in this family can consist of over 1,000 individual flowers (also known as florets), and the heads themselves can be grouped into more complex arrangements called capitulescences. The flowers in the outermost rows often have a modified, flat, and elongated corolla that looks like a petal of a regular flower.
2 Britannica Sources
1. Asterales
2. Asteraceae: Flowers
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
Where can you commonly find plants from the Asterales order around the world?
The Asteraceae family, also known as the aster, daisy, or composite family, is within the order Asterales. It contains over 1,620 genera and 25,000 species of herbs, shrubs, and trees distributed throughout the world. The order Asterales has 11 families and about 26,870 species. Paleobotanists believe the first members of this family evolved in Argentina around 50 million years ago.
2 Britannica Sources
1. Asterales
2. Asteraceae
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
Why is the Asterales order important to humans and the environment?
The Asterales order, containing around 26,870 species across 11 families, significantly impacts humans and the environment.

Many species are cultivated as garden ornamentals, such as asters, chrysanthemums, and marigolds. Economically important food crops include artichokes, lettuce, endive, sunflower, and safflower, the seeds of which are used to produce cooking oils. Some Asterales, like wormwood, are sources of poisonous oils. Certain species, such as marigolds, release compounds that kill plant-parasitic nematodes in the soil.

However, some members, including ragweed and thistle, are troublesome weeds; ragweed is a significant allergen.
3 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Asterales, daisy order of flowering plants, containing 11 families and some 26,870 species. Asterales is part of the core asterid clade (organisms with a single common ancestor) in the euasterid II group of the Angiosperm Phylogeny Group III (APG III) botanical classification system. The major families are Asteraceae and Campanulaceae (including Lobeliaceae), with far fewer species in the remaining families of Goodeniaceae, Stylidiaceae, Menyanthaceae, Calyceraceae, Rousseaceae (including Carpodetaceae), Pentaphragmataceae, Alseuosmiaceae, Phellinaceae, and Argophyllaceae. These families have been genetically linked to one another by their common chemical characteristics, such the presence of ellagic acid and inulin, and by their morphological similarities, including a specialized mechanism known as plunger pollination.

Asteraceae

Asteraceae is a large family of flowering plants, with more than 1,620 genera and 23,600 species. The only other plant family with a comparable number of species is Orchidaceae, the orchid family, in the order Asparagales. Members of Asteraceae occur in nearly every terrestrial habitat, though most are herbs in temperate and subtropical regions. Several species are adapted to harsh locations, such as sand dunes; cliff crevices; talus slopes; seleniferous, gypsiferous, or alkaline soils; and fields or disturbed sites around human habitations. A few species are aquatic. In most temperate regions, more than 10 percent of the species of flowering plants belong to Asteraceae.

SunflowerThe flowering head of a sunflower (*Helianthus annuus*) is formed of yellow, petal-like ray flowers and a brown center of minute disk flowers.

The most obvious and outstanding general feature of Asteraceae is that the flowers are grouped characteristically into compact inflorescences (heads) that superficially resemble individual flowers. Each such head is ordinarily subtended by an involucre of small modified leaves (bracts). Furthermore, in more than half the members of the family, the flowers in the outermost row or rows of the head have a modified, mainly flat and elongate corolla that resembles an individual petal of most other flowers. Thus, the “petals” of a daisy or sunflower are actually the outermost flowers of the head. An inflorescence of this family can have more than 1,000 individual flowers (called florets), and the heads can be grouped into more complex, secondary arrangements called capitulescences.

The leaves of Asteraceae are simple or occasionally compound, and their arrangement along the stem may be opposite, alternate, or whorled. The one-seeded fruit (an achene) has a hard outer covering and is often accompanied by sepals that have been reduced to a ring of hairs, scales, or bristles, known as the pappus. The parachute-like pappi of Taraxacum officinale (dandelion) exploit wind currents to facilitate seed distribution, whereas other genera, such as Bidens (beggar-tick), employ barbed pappus awns to utilize the movement of animals in seed transportation.

The evolutionary success of Asteraceae may be attributable to its arsenal of defensive secondary metabolites. While it lacks the iridoid compounds found in other orders of the core asterid lineage of flowering plants, Asteraceae heavily exploits polyacetylenes, bitter sesquiterpenes (especially sesquiterpene lactones), terpenoid volatile oils, latex, several kinds of alkaloids (notably pyrrolizidine alkaloids in the tribe Senecioneae), and various other compounds. Members of the genus Tagetes (marigolds) kill plant-parasitic nematodes in the soil by releasing terpenoid compounds from their roots. The polyacetylenes found in Asteraceae generally have cyclic, aromatic, or heterocyclic end groups, in contrast to the mainly aliphatic polyacetylenes of Campanulaceae.

Venus's-flytrap. Venus's-flytrap (Dionaea muscipula) one of the best known of the meat-eating plants. Carnivorous plant, Venus flytrap, Venus fly trap

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cornflowerCornflower, or bachelor's button (*Centaurea cyanus*).

Much of the economic importance of Asteraceae lies in the use of many of its members as garden ornamentals. Species and garden hybrids of Aster (Michaelmas daisy), Bellis (English daisy), Callistephus (China aster), Chrysanthemum (chrysanthemum, daisy), Cosmos (cosmos), Dahlia (dahlia), Echinacea (coneflower), Helianthus (sunflower), Rudbeckia (black-eyed Susan), Tagetes (marigold), and Zinnia (zinnia) are well-known garden favourites. Also familiar in gardens are Achillea (yarrow), Ageratum (ageratum), Anaphalis (pearly everlasting), Anthemis (golden marguerite), Artemisia (wormwood), Calendula (pot marigold), Centaurea (bachelor’s button, or cornflower), Echinops (globe thistle), Erigeron (fleabane), Eupatorium (joe-pye weed, boneset, white snakeroot), Gaillardia (blanketflower), Helichrysum (strawflower, everlasting), Liatris (blazing star, button snakeroot), Ratibida (coneflower), Santolina (lavender cotton), and Stokesia (Stokes’ aster). Cineraria, a popular wintertime potted flower, is Senecio cruentus, originally from the Canary Islands.

The ragweeds (Ambrosia), dandelions (Taraxacum), and thistles (Carduus, Cirsium, and Onopordum) are the most troublesome weeds in Asteraceae. Ambrosia artemisiifolia (common ragweed) and Ambrosia trifida (giant ragweed) are two of the most significant plant species causing the allergic reaction known as hay fever.

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The family also has several food plants that are economically significant. The most important of these is Lactuca sativa (lettuce), a European cultigen. Second in importance is Helianthus annuus (sunflower), a native of North America. Sunflower seeds are excellent poultry feed and produce an oil commonly used as a salad or cooking oil, as well as in the manufacture of margarine, soap, paint, and varnish. Oil cake is fed to livestock, and the whole plant is used as silage. Flowers of Carthamus tinctorius (safflower) are the source of red and yellow dyes, and the seeds produce an oil used in cooking and in the production of soap, paint, and varnish. Several other members of the order, including Cynara scolymus (artichoke) and Helianthus tuberosus (Jerusalem artichoke), are of lesser importance as food plants.

Asteraceae also features several species from which a variety of important chemical substances are derived. Pyrethrum, an insecticide that does not produce the environmental problems associated with many synthetic products, is obtained from the flowers of several species, particularly Tanacetum cinerariifolium. Extracts from several species of wormwood, notably Artemisia cina from the Middle East, are used to expel intestinal worms (e.g., pinworms). A. absinthium is the source of a poisonous oil used to give the liqueur absinthe its distinctive character. A sesquiterpene extracted from A. annua (a Eurasian weed) is increasingly used in the treatment of quinine-resistant malaria.

Asterales

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