''Matricaria discoidea'', commonly known as pineappleweed, wild chamomile, disc mayweed, and rayless mayweed, is an

annual plant An annual plant is a plant that completes its life cycle, from germination to the production of seeds, within one growing season, and then dies. Globally, 6% of all plant species and 15% of herbaceous plants (excluding trees and shrubs) are ...

native to North America and/or

northern Asia North Asia or Northern Asia () is the northern region of Asia, which is defined in geographical terms and consists of three federal districts of Russia: Ural, Siberian, and the Far Eastern. North Asia is bordered by the Arctic Ocean to its n ...

, introduced to

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

where it grows as a common herb of fields, gardens, and roadsides. It is in the daisy family

Asteraceae Asteraceae () is a large family (biology), family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the Order (biology), order Asterales. The number of species in Asteraceae is rivaled only by the Orchi ...

. The flowers exude a

chamomile Chamomile (American English) or camomile (British English; see spelling differences) ( or ) is the common name for several plants of the family Asteraceae. Two of the species, '' Matricaria chamomilla'' and '' Chamaemelum nobile'', are commo ...

pineapple The pineapple (''Ananas comosus'') is a Tropical vegetation, tropical plant with an edible fruit; it is the most economically significant plant in the family Bromeliaceae. The pineapple is indigenous to South America, where it has been culti ...

aroma when crushed. They are edible and have been used in salads (although they may become bitter by the time the plant blooms) and to make herbal tea.

Description

The

flower head A pseudanthium (; : pseudanthia) is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, composite flowers ...

pseudanthium A pseudanthium (; : pseudanthia) is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, composite flowers ...

is cone-shaped, composed of densely packed yellowish-green corollas, and lacking ray-florets. The

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

are pinnately dissected and sweet-scented when crushed. The plant grows high. Flowerheads are produced from March to September.

Distribution and habitat

The plant grows well in disturbed areas, especially those with poor, compacted

soil Soil, also commonly referred to as earth, is a mixture of organic matter, minerals, gases, water, and organisms that together support the life of plants and soil organisms. Some scientific definitions distinguish dirt from ''soil'' by re ...

. It can be seen blooming on footpaths, roadsides, and similar places in spring and early summer. Some sources say it is native to North America, from central

Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...

south to

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

and

Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...

and east to

Nova Scotia Nova Scotia is a Provinces and territories of Canada, province of Canada, located on its east coast. It is one of the three Maritime Canada, Maritime provinces and Population of Canada by province and territory, most populous province in Atlan ...

and

Greenland Greenland is an autonomous territory in the Danish Realm, Kingdom of Denmark. It is by far the largest geographically of three constituent parts of the kingdom; the other two are metropolitan Denmark and the Faroe Islands. Citizens of Greenlan ...

.Other sources list it as only native to the

Pacific Northwest The Pacific Northwest (PNW; ) is a geographic region in Western North America bounded by its coastal waters of the Pacific Ocean to the west and, loosely, by the Rocky Mountains to the east. Though no official boundary exists, the most common ...

or as introduced to North America, native to

Siberia Siberia ( ; , ) is an extensive geographical region comprising all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has formed a part of the sovereign territory of Russia and its predecessor states ...

. Alongside a variety of other plant species, wild chamomile seeds are known to be inadvertently transported to new areas through soil carried by

car A car, or an automobile, is a motor vehicle with wheels. Most definitions of cars state that they run primarily on roads, seat one to eight people, have four wheels, and mainly transport people rather than cargo. There are around one billio ...

s; A study by Dunmail J. Hodkinson and Ken Thompson found that M. discoidea is one of the most common plants to be transported in this way. It has been introduced widely in the northern hemisphere and is common and naturalized throughout Britain where it is one of the fastest-spreading plants in the 20th century.

Uses

The greens can be washed and eaten, and both the flowers and the whole plant can be steeped to make tea, described as "excellent" by one field guide.

Gallery

File:Matricaria discoidea 2637.JPG, The pinnately dissected leaves are sweet-scented when crushed File:Chamomilla suaveolens kz.jpg File:20130602Matricaria discoidea1.jpg File:Pineapple Mayweed (Chamomilla suaveolens) - geograph.org.uk - 497544.jpg File:Matricaria discoidea by Danny S. - 002.JPG

References

External links

USDA Plants Profile for ''Matricaria discoidea'' (Disc mayweed, Pineapple weed)

Jepson Manual treatment: for ''Chamomilla suaveolens'' —''Matricaria discoidea''

University of Michigan Native American Ethnobotany — ''Matricaria discoidea''

* Robbins, W. W., Margaret K. Bellue, and Walter S. Ball. 1970. ''Weeds of California''. Documents and Publications, Sacramento. 547 p. * Gregory L. Tilford. 1997. ''Edible and Medicinal Plants of the West''. Mountain Press Publishing Company, Missoula. 110 p.

* * {{DEFAULTSORT:Matricaria Discoidea discoidea Edible plants Flora of Northeast Asia Flora of Japan Flora of Alaska Flora of Yukon Flora of Alberta Flora of British Columbia Flora of the Northwestern United States Flora of the Southwestern United States Flora of the Sierra Nevada (United States) Flora of California Flora of Baja California Taxa named by Augustin Pyramus de Candolle Flora without expected TNC conservation status