Ragweeds are flowering plants in the genus Ambrosia in the aster family, Asteraceae. They are distributed in the tropical and subtropical regions of the Americas, especially North America, where the origin and center of diversity of the genus are in the southwestern United States and northwestern Mexico. Several species have been introduced to the Old World and some have naturalized and have become invasive species. Ragweed species are expected to continue spreading across Europe in the near future in response to ongoing climate change.
Ambrosia dumosa, the burro-weed or white bursage, a North American species of plants in the family Asteraceae. It is a common constituent of the creosote-bush scrub community throughout the Mojave desert of California, Nevada, and Utah and the Sonoran Desert of Arizona and northwestern Mexico.
Ambrosia trifida, the giant ragweed, is a species of flowering plant in the family Asteraceae. It is native to North America, where it is widespread in Canada, the United States, and northern Mexico.
Ambrosia ambrosioides, also known as canyon ragweed or chicura, is a ragweed found in the deserts of northern Mexico, Arizona, and California.
Ambrosia acanthicarpa is a North American species of bristly annual plants in the family Asteraceae. Members of the genus Ambrosia are called ragweeds. The species has common names including flatspine bur ragweed, Hooker's bur-ragweed, annual burrweed, annual bur-sage, and western sand-bur. The plant is common across much of the western United States and in the Prairie Provinces of Canada.
Ambrosia psilostachya is a species of ragweed known by the common names Cuman ragweed and perennial ragweed, and western ragweed.
Ambrosia chenopodiifolia is a species of ragweed known by the common names San Diego bursage and San Diego bur ragweed. It is native to the Mexican states of Baja California and Baja California Sur, as well as to Orange and San Diego Counties it int US State of California. It is a member of the coastal sage scrub plant community.
Ambrosia confertiflora is a North American species of ragweed known by the common name weakleaf bur ragweed.
Ambrosia eriocentra is a North American species of ragweed known by the common names woolly bursage and woollyfruit burr ragweed.
Ambrosia ilicifolia is a species of ragweed known by the common names hollyleaf burr ragweed and hollyleaf bursage.
Ambrosia pumila is a rare species of herbaceous perennial plant known by the common names San Diego ragweed and San Diego ambrosia. It is native to far southern California, Baja California, and Baja California Sur. It grows in floodplains and open grasslands in proximity to wetland areas.
Antennaria rosea is a North American species of flowering plant in the family Asteraceae known by the common name rosy pussytoes. Other common names include cat's foot and mountain everlasting. The second part of its scientific name, rosea, is Latin for pink. It is widespread across much of Canada including all three Arctic territories, as well as Greenland, the western and north-central United States, and the Mexican state of Baja California.
Antennaria suffrutescens is a species of flowering plant in the family Asteraceae known by the common names evergreen pussytoes and evergreen everlasting. It is native to southwestern Oregon and far northeastern California. It grows in coniferous forests in the mountains, sometimes on serpentine soils.
Bernardia myricifolia is a species of flowering plant in the spurge family known by the common name mouse's eye. It is also called mouse ear, or oreja de ratón in Spanish. It is native to Texas, New Mexico, and Mexico. It grows in shrub communities on rocky, limestone hills. This is a perennial shrub growing over three meters in maximum height. The small leaves are each up to three centimeters long, oval in shape, with scallop-shaped teeth along the edges. A dioecious species, male and female individuals produce different types of flowers. Staminate inflorescences are small clusters of male flowers, and pistillate inflorescences bear solitary female flowers. The fruit is a roughly rounded woolly capsule with three prominent chambers, each containing a seed.
Cirsium mohavense is a species of thistle known by the common names virgin thistle and Mojave thistle. It is native to the southwestern United States, where it grows in moist areas in otherwise dry habitat, such as desert springs. It is most common in the Mojave Desert, found also in the southern Great Basin and other nearby regions of California, Nevada, western Arizona, and southwestern Utah.
Tetracoccus ilicifolius is a rare species of flowering shrub in the family Picrodendraceae known by the common names hollybush and holly-leaved tetracoccus.
Ambrosia cheiranthifolia is a rare species of flowering plant known by the common names South Texas ambrosia and Rio Grande ragweed. It is native to the coast of South Texas and the Mexican states of Tamaulipas and Coahuila. It occurs in coastal prairie, grassland, and mesquite shrubland habitat. It has declined because its native habitat has been cleared for development, with remaining open savanna invaded by non-native grasses such as buffelgrass. Today there are perhaps 20 populations remaining, but some of these may have very few genetic individuals because the species is clonal, with many cloned plants attached by one rhizome. It is not certain that the plant still exists in Mexico. This is a federally listed endangered species of the United States.
Ambrosia deltoidea is a North American species of flowering plant in the family Asteraceae known by the common names triangle bur ragweed, triangle bursage, and triangleleaf bursage.
Ambrosia linearis is a species of flowering plant in the family Asteraceae known by the common names streaked bur ragweed, Colorado bursage, linear-leaf bursage, and plains ragweed. It is endemic to east-central part of the state of Colorado in the United States, where it occurs in Elbert, Pueblo, El Paso, Cheyenne, Crowley, Kiowa and Lincoln Counties.
Ambrosia salsola, commonly called cheesebush, winged ragweed, burrobush, white burrobrush, and desert pearl, is a species of perennial shrub in the family Asteraceae native to deserts of the southwestern United States and northwestern Mexico.
