Mayweed
Encyclopedia
Matricaria is a genus
of flowering plants in the sunflower family (Asteraceae
). Some of the species have the common name of "mayweed," but this name also refers to plants not in this genus.
Most are very common in the temperate regions of Europe, Asia, and America, as well as in northern and southern Africa, and some are naturalised in Australia. M. occidentalis is native to North America; other species have been introduced there.
These are hardy, pleasantly aromatic
annuals
, growing along roadsides in ruderal communities and in fallow land rich in nutrients. Though many are considered nuisance weed
s, they are suitable for rock gardens and herb gardens, and as border plants.
Their many-branched stems
are prostrate to erect, glabrous, and very leafy. Their bipinnate leaves
have numerous linear, narrowly lobed leaflets.
The flower
s are radially symmetrical. The greenish-yellow capitula
are semi-spherical. The white ray florets can be present (M. recutita) or lacking (M. discoidea). The disc florets are 4- to 5-dentate. The receptacle is 2–3 times as high as wide. The pappus
may be crown-shaped and short, or lacking.
Matricaria species are used as food plants by the larva
e of some Lepidoptera
species (caterpillar
s) including Lime-speck Pug
.
The extract
of German chamomile
(M. recutita) is taken as a strong tea. It has been used in herbal medicine as a carminative
and anti-inflammatory. It is also used in ointments and lotions, and as a mouthwash against infections of mouth and gums. Aromatherapy
uses two essential oils of chamomile: the "true chamomile" oil (or German chamomile oil, from M. recutita) and the Roman chamomile oil (from Anthemis
nobilis).
The taxonomy
of Matricaria is controversial and very confused. Several species are classified either in Tripleurospermum
or Matricaria depending on the interpretation of the author. The distinction is made according to the number of the seed ribs: Tripleurospermum has one adaxial and two lateral seed ribs, while Matricaria has four or five adaxial seed ribs.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of flowering plants in the sunflower family (Asteraceae
Asteraceae
The Asteraceae or Compositae , is an exceedingly large and widespread family of vascular plants. The group has more than 22,750 currently accepted species, spread across 1620 genera and 12 subfamilies...
). Some of the species have the common name of "mayweed," but this name also refers to plants not in this genus.
Most are very common in the temperate regions of Europe, Asia, and America, as well as in northern and southern Africa, and some are naturalised in Australia. M. occidentalis is native to North America; other species have been introduced there.
These are hardy, pleasantly aromatic
Aroma compound
An aroma compound, also known as odorant, aroma, fragrance or flavor, is a chemical compound that has a smell or odor...
annuals
Annual plant
An annual plant is a plant that usually germinates, flowers, and dies in a year or season. True annuals will only live longer than a year if they are prevented from setting seed...
, growing along roadsides in ruderal communities and in fallow land rich in nutrients. Though many are considered nuisance weed
Weed
A weed in a general sense is a plant that is considered by the user of the term to be a nuisance, and normally applied to unwanted plants in human-controlled settings, especially farm fields and gardens, but also lawns, parks, woods, and other areas. More specifically, the term is often used to...
s, they are suitable for rock gardens and herb gardens, and as border plants.
Their many-branched stems
Plant stem
A stem is one of two main structural axes of a vascular plant. The stem is normally divided into nodes and internodes, the nodes hold buds which grow into one or more leaves, inflorescence , conifer cones, roots, other stems etc. The internodes distance one node from another...
are prostrate to erect, glabrous, and very leafy. Their bipinnate leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
have numerous linear, narrowly lobed leaflets.
The flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s are radially symmetrical. The greenish-yellow capitula
Head (botany)
The capitulum is considered the most derived form of inflorescence. Flower heads found outside Asteraceae show lesser degrees of specialization....
are semi-spherical. The white ray florets can be present (M. recutita) or lacking (M. discoidea). The disc florets are 4- to 5-dentate. The receptacle is 2–3 times as high as wide. The pappus
Pappus (flower structure)
The pappus is the modified calyx, the part of an individual disk, ray or ligule floret surrounding the base of the corolla, in flower heads of the plant family Asteraceae. The pappus may be composed of bristles , awns, scales, or may be absent. In some species, the pappus is too small to see...
may be crown-shaped and short, or lacking.
Matricaria species are used as food plants by the larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e of some Lepidoptera
Lepidoptera
Lepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...
species (caterpillar
Caterpillar
Caterpillars are the larval form of members of the order Lepidoptera . They are mostly herbivorous in food habit, although some species are insectivorous. Caterpillars are voracious feeders and many of them are considered to be pests in agriculture...
s) including Lime-speck Pug
Lime-speck Pug
The Lime-speck Pug is a moth of the family Geometridae. It is a common species throughout the Palearctic region, the Near East and North Africa....
.
The extract
Extract
An extract is a substance made by extracting a part of a raw material, often by using a solvent such as ethanol or water. Extracts may be sold as tinctures or in powder form....
of German chamomile
German Chamomile
Matricaria chamomilla or German chamomile, also spelled camomile, is an annual plant of the composite family Asteraceae. Synonyms are: Chamomilla chamomilla, Chamomilla recutita , Matricaria recutita, and Matricaria suaveolens.-Distribution:It usually grows near populated areas all over Europe and...
(M. recutita) is taken as a strong tea. It has been used in herbal medicine as a carminative
Carminative
A carminative, also known as carminativum , is a herb or preparation that either prevents formation of gas in the gastrointestinal tract or facilitates the expulsion of said gas, thereby combating flatulence...
and anti-inflammatory. It is also used in ointments and lotions, and as a mouthwash against infections of mouth and gums. Aromatherapy
Aromatherapy
Aromatherapy is a form of alternative medicine that uses volatile plant materials, known as essential oils, and other aromatic compounds for the purpose of altering a person's mind, mood, cognitive function or health....
uses two essential oils of chamomile: the "true chamomile" oil (or German chamomile oil, from M. recutita) and the Roman chamomile oil (from Anthemis
Anthemis
Anthemis is a genus of about 100 species of aromatic herbs in the Asteraceae, closely related to Chamaemelum, and like that genus, known by the common name chamomile; some species are also called dog-fennel or mayweed. However, Mayweed is improperly used for this genus since Mayweed refers to the...
nobilis).
The taxonomy
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
of Matricaria is controversial and very confused. Several species are classified either in Tripleurospermum
Tripleurospermum
Tripleurospermum is a genus in the family Asteraceae in the tribe Anthemideae. The classification of the 38 annual and herbaceous perennial species is problematic. Most of the species are from Europe and temperate Asia although a few are from North America and North Africa. The species are placed...
or Matricaria depending on the interpretation of the author. The distinction is made according to the number of the seed ribs: Tripleurospermum has one adaxial and two lateral seed ribs, while Matricaria has four or five adaxial seed ribs.
Species
- Matricaria acutiloba
- Matricaria albida
- Matricaria arabica
- Matricaria arlgirdensis
- Matricaria aurea (Loefl.) Sch. Bip.
- Matricaria auriculata
- Matricaria brachyglossa
- Matricaria burchellii
- Matricaria capitellata
- Matricaria confusa
- Matricaria coreana
- Matricaria corymbifera
- Matricaria courrantiana DC. -- Crown Mayweed
- Matricaria decipiens
- Matricaria dichotoma
- Matricaria discoidea DC. -- Disc Mayweed, Pineapple Weed, Rounded Chamomile
- Matricaria fuscata
- Matricaria glabra (synonym of Otospermum glabrum (Lag.) Willk.)
- Matricaria glabrata
- Matricaria globifera
- Matricaria grandiflora
- Matricaria hirsutifolia
- Matricaria hirta
- Matricaria hispida
- Matricaria intermedia
- Matricaria lamellata
- Matricaria lasiocarpa
- Matricaria laxa
- Matricaria macrotis
- Matricaria melanophylla
- Matricaria microcephala
- Matricaria nigellifolia
- Matricaria occidentalis Greene—Valley Mayweed
- Matricaria otaviensis
- Matricaria pinnatifida
- Matricaria recutita L. -- German Chamomile, Scented Mayweed, Wild Chamomile, Common Chamomile
- Matricaria raddeana
- Matricaria schinzinna
- Matricaria spathipappus
- Matricaria subglobosa
- Matricaria suffruticosa
- Matricaria tridentata
- Matricaria tzvelevii (synonym of Chamomilla tzvelevii (Pobed.) Rauschert)