The small marsh flower ''Cotula coronopifolia'' bears the common names brass buttons, golden buttons, and buttonweed. The flower heads are bright yellow

discoid Discoid may refer to: * Disk (mathematics), the region in a plane enclosed by a circle Medicine * Furosemide, a medication sold under the trade name Discoid * Discoid meniscus, a human anatomical variant * Discoid lupus erythematosus, a chroni ...

heads that look like thick buttons. Individual plants spread stems along the ground and send up the knobby flowers at intervals. The plant is native to southern

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

, as well as

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

, but it has been introduced to other parts of the world (

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North North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating direction or geography. Etymology The word ''north ...

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sout ...

, etc.).Flora of North America, Brass-buttons, cotule, Cotula coronopifolia Linnaeus, Sp. Pl. 2: 892. 1753.
/ref> Brass buttons are common plants that occupy a specialized

ecological niche In ecology, a niche is the match of a species to a specific environmental condition. Three variants of ecological niche are described by It describes how an organism or population responds to the distribution of resources and competitors (for ...

. They prefer muddy,

anoxic The term anoxia means a total depletion in the level of oxygen, an extreme form of hypoxia or "low oxygen". The terms anoxia and hypoxia are used in various contexts: * Anoxic waters, sea water, fresh water or groundwater that are depleted of diss ...

wetland A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The p ...

s and

brackish water Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuari ...

. They are very salt-tolerant. The plant has fat, fleshy leaves that store water during times of saline inundation. The reddish stems and green, blade-shaped leaves are coated with a shiny cuticle to retain moisture. It can also be found in the wetter patches in

vernal pool Vernal pools, also called vernal ponds or ephemeral pools, are seasonal pools of water that provide habitat for distinctive plants and animals. They are considered to be a distinctive type of wetland usually devoid of fish, and thus allow the safe ...

ecosystems. Brass buttons are common along beaches,

salt marsh A salt marsh or saltmarsh, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides. It is domin ...

es, and estuaries from

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. It has been present in the British Isles since the late 1800s, especially on the Cheshire coast and is considered a

neophyte A neophyte is a recent initiate or convert to a subject or belief. Neophyte may also refer to: Science * Neophyte (botany), a plant species recently introduced to an area As a proper noun Arts and entertainment * Neophyte, a character class ...

naturalised plant. Although brass buttons is known to be invasive, its spread appears to be relatively slow. Its California Invasive Plant Council Inventory rating is "limited", that is, "invasive but their ecological impacts are minor on a statewide level or there was not enough information to justify a higher score. Their reproductive biology and other attributes result in low to moderate rates of invasiveness. Ecological amplitude and distribution are generally limited, but these species may be locally persistent and problematic."California Invasive Plant Inventory Accessed Dec. 19, 2013
/ref>

Gallery

Cotula coronopifolia 108269598.jpg Cotula coronopifolia 2.jpg Cotula coronopifolia 7776.JPG, Leaves sheath the stem and are

entire Entire may refer to: * Entire function, a function that is holomorphic on the whole complex plane * Entire (animal), an indication that an animal is not neutered * Entire (botany) This glossary of botanical terms is a list of definitions of ...

or with a few teeth or deep lobes ( Fir Island,

) Cotula coronopifolia - Flickr - Kevin Thiele.jpg

References

External links

Jepson Manual ''Cotula coronopifolia''''Cotula coronopifolia'' occurrence data
from

GBIF The Global Biodiversity Information Facility (GBIF) is an international organisation that focuses on making scientific data on biodiversity available via the Internet using web services. The data are provided by many institutions from around the ...

* {{Taxonbar, from=Q2998623 coronopifolia Plants described in 1753 Taxa named by Carl Linnaeus Flora of South Africa