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. In Europe, this spread is expected to continue, due 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.
Lycium andersonii is a species of flowering plant in the nightshade family, Solanaceae. Its common names include water-jacket, redberry desert-thorn, Anderson thornbush, Anderson's desert thorn, Anderson boxthorn, Anderson lycium, Anderson wolfberry, and squawberry.
Ambrosia chamissonis is a species of ragweed known by the common names silver burr ragweed, silver beachweed and (silver) beach bur(r).
Adenophyllum porophylloides is a species of flowering plant in the family Asteraceae known by the common names San Felipe dogweed and San Felipe dyssodia. It is native to the Sonoran and Mojave Deserts of the southwestern United States and northwestern Mexico. It grows in alluvial fans, rocky slopes, open scrub and woodlands.
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.
Artemisia arbuscula is a North American species of sagebrush known by the common names little sagebrush, low sagebrush, or black sagebrush. It is native to the western United States from Washington, Oregon, and California east as far as Colorado and Wyoming. It grows in open, exposed habitat on dry, sterile soils high in rock and clay content.
Cirsium crassicaule is a species of thistle known by the common name slough thistle. It is endemic to the San Joaquin Valley of California, where it is known primarily from freshwater wetlands. It has been found in only a few locations in Kern, Kings, and San Joaquin Counties.
Corethrogyne is a monotypic genus of flowering plant in the family Asteraceae. Its only species is Corethrogyne filaginifolia, known by the common names common sandaster and California aster.
Anisocarpus madioides is a North American species of flowering plant in the family Asteraceae known by the common name woodland madia.
Bahiopsis laciniata is a species of flowering plant in the family Asteraceae known by the common names San Diego County sunflower, San Diego viguiera and tornleaf goldeneye. It is native to the deserts and dry mountain slopes of northwestern Mexico, its distribution extending north as far as Ventura County, California.
Agnorhiza ovata is a species of flowering plant known by the common name southern mule's ears. It is native to the mountains and foothills of southern California and Baja California, occurring the Coast Ranges and Sierra Nevada foothills in Tulare, Kern, Ventura, Los Angeles, Orange, Riverside, and San Diego counties in California, with additional populations in the Peninsular Ranges south of the international border.
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 cordifolia, called the Tucson bur ragweed, is a North American species of plant in the family Asteraceae. It is native to northern Mexico and the State of Arizona in the United States.
