Flaveria trinervia
Encyclopedia
Flaveria trinervia is a species of flowering plant in the aster family
known by the common name clustered yellowtops. It is native to parts of the Americas, including the southeastern and southwestern United States, most of Mexico, and parts of the Caribbean
, but it is known in many other places as an introduced species
and often a noxious weed, such as in Hawaii
. It grows easily in many types of wet habitat, including saline and alkaline soils and highly disturbed habitat. This is an annual herb growing erect and known to exceed two meters in maximum height. The lance-shaped to oval leaves are each up to 15 centimeters long and arranged oppositely in pairs around the stem, their bases sometimes fused together. The edges of the leaves generally have tiny widely-spaced teeth. The inflorescence
is a large dense cluster of many flower heads
, sometimes over 300 in one cluster. Each flower head is either radiate, bearing one single yellowish ray floret, or discoid, bearing one or two smaller disc florets.
This plant exhibits C4 carbon fixation
.
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...
known by the common name clustered yellowtops. It is native to parts of the Americas, including the southeastern and southwestern United States, most of Mexico, and parts of the Caribbean
Caribbean
The Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...
, but it is known in many other places as an introduced species
Introduced species
An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...
and often a noxious weed, such as in Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...
. It grows easily in many types of wet habitat, including saline and alkaline soils and highly disturbed habitat. This is an annual herb growing erect and known to exceed two meters in maximum height. The lance-shaped to oval leaves are each up to 15 centimeters long and arranged oppositely in pairs around the stem, their bases sometimes fused together. The edges of the leaves generally have tiny widely-spaced teeth. The inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
is a large dense cluster of many flower heads
Head (botany)
The capitulum is considered the most derived form of inflorescence. Flower heads found outside Asteraceae show lesser degrees of specialization....
, sometimes over 300 in one cluster. Each flower head is either radiate, bearing one single yellowish ray floret, or discoid, bearing one or two smaller disc florets.
This plant exhibits C4 carbon fixation
C4 carbon fixation
C4 carbon fixation is one of three biochemical mechanisms, along with and CAM photosynthesis, used in carbon fixation. It is named for the 4-carbon molecule present in the first product of carbon fixation in these plants, in contrast to the 3-carbon molecule products in plants. fixation is an...
.