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Artemisia matricarioides auct.
Matricaria discoidea, commonly known as pineappleweed, wild chamomile, and disc mayweed is an annual plant native to North America and Northeast Asia but which has become a cosmopolitan weed. It is in the family Asteraceae. The flowers exude a chamomile/pineapple 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. Pineapple weed has been used for medicinal purposes, including for relief of gastrointestinal upset, infected sores, fevers, and postpartum anemia.
The flower head is cone-shaped, composed of dense-packed yellowish-green corollas, and lacking ray-florets. The leaves are pinnately dissected and sweet-scented when crushed. The plant grows 2 to 16 inches (5.1 to 40.6 cm) high. Flowerheads are produced from March to September.
The plant grows well in disturbed areas, especially those with poor, compacted soil. It can be seen blooming on footpaths, roadsides, and similar places in spring and early summer. In North America, it can be found from central Alaska down to California and all the way to Nova Scotia and Newfoundland. It has also become common and naturalised in Britain 
- Russian Far East: Amur Oblast, Kamchatka Peninsula, Khabarovsk Krai, Kuril Islands, Magadan Oblast, Primorsky Krai, Sakhalin
- Eastern Asia: Hokkaido
- Subarctic America: Yukon Territory, Alaska
- Western Canada: Alberta, Saskatchewan, British Columbia, Manitoba,
- Eastern Canada: Québec
- Northwestern United States: Idaho, Montana, Oregon, Washington, Wyoming
- Southwestern United States: Arizona, California, Nevada, Utah, Colorado
- Mexico Northwest: Baja California
- "Matricaria discoidea". Natural Resources Conservation Service PLANTS Database. USDA. Retrieved 2008-06-14.
- Germplasm Resources Information Network (GRIN) (2005-09-07). "Taxon: Matricaria discoidea DC.". Taxonomy for Plants. USDA, ARS, National Genetic Resources Program, National Germplasm Resources Laboratory, Beltsville, Maryland. Retrieved 2008-06-14.
- "BSBI List 2007" (xls). Botanical Society of Britain and Ireland. Archived from the original on 2015-02-25. Retrieved 2014-10-17.
- The Wildlife Trusts, "Pineappleweed" http://www.wildlifetrusts.org/species/pineappleweed
|Wikimedia Commons has media related to Matricaria discoidea.|
- 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
- Pineapple weed - 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.
- University of California-Davis, Statewide Integrated Pest Management Program — 'Pineapple weed'
- Den virtuella floran: Matricaria discoidea distribution
- Matricaria discoidea — U.C. CalPhotos Gallery