Mayweed Chamomile (Noxious Weeds of Colorado)

Mayweed Chamomile

Anthemis cotula

Summary ⁴

Mayweed chamomile (Anthemis cotula), also known as stinking chamomile, is a bushy annual native to Europe. Flowers are solitary and borne at the ends of branches. They are 0.75 to 1.25 inches in diameter with approximately 12 white ray florets and yellow disk centers. Flowers bloom from June through September. Mature plants can produce up to 960,000 seeds per plant, which remain viable for 4 to 6 years. Plants grow up to 2 feet tall and are highly branched. The leaves are finely dissected, alternate, and are approximately 0.75 to 2.5 inches long and 1 inch wide. Contact with Mayweed chamomile can cause skin rashes, blistering of livestock muzzles and irritated mucus membranes of grazing livestock.

Source:
https://drive.google.com/file/d/1d4fjTsbmmIiL9h-2A7G2WG2fHRFbiQl0/view
http://www.cwma.org/Mayweed.html

Identification ⁵

Height: 0.5-2 feet tall
Shape: Bushy forb
Flowers: Flowers are solitary and borne at the ends of branches. Flowers are 0.75-1.25 in wide with approximately 12 white ray florets and a yellow disk center. White ray florets have 3 distinct teeth. Flowers June-September
Stems: Stems are highly branched, and have a foul odor. Lower portion often turns a maroon as the stem ages.
Leaves: The leaves are finely dissected, alternate, and approximately 0.75 to 2.5 inches long and 1 inch wide. Leaves may have some short hairs and emit an unpleasant odor when crushed.
Fruit: Small, single-seeded fruit (achene) with about 10 ribs and small glandular bumps
Toxic: Contact with mayweed chamomile can cause skin rashes, blistering of livestock muzzles, and irritation to mucous membranes of grazing livestock. It may also impart a strong flavor to the milk of dairy animals
Root: Taproot with secondary fibrous root system

Source:
https://drive.google.com/file/d/1d4fjTsbmmIiL9h-2A7G2WG2fHRFbiQl0/view
http://www.cwma.org/Mayweed.html

Origin/Habitat ⁵

Mayweed chamomile is native to Europe. It is commonly found in ditches, roadsides, urban areas, waste places, cultivated fields, and pastures. It can grow in a wide range of soils but seems to prefer moist, poorly drained soils. It prefers moist areas and increases in abundance during years with above average precipitation.

Source:
https://drive.google.com/file/d/1d4fjTsbmmIiL9h-2A7G2WG2fHRFbiQl0/view
http://www.cwma.org/Mayweed.html

Sources and Credits

(c) Alex Abair, some rights reserved (CC BY-NC), uploaded by Alex Abair
(c) 2008 Keir Morse, some rights reserved (CC BY-NC-SA), http://calphotos.berkeley.edu/cgi/img_query?seq_num=267449&one=T
(c) 2008 Keir Morse, some rights reserved (CC BY-NC-SA), http://calphotos.berkeley.edu/cgi/img_query?seq_num=267454&one=T
Adapted by Colorado Parks and Wildlife from a work by (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Anthemis_cotula
(c) Colorado Parks and Wildlife, some rights reserved (CC BY-SA)

More Info

iNat Map

Color	white, yellow
Species status	List B
Growth form	Flowering Plants

‹ › ×