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.
Eryngium articulatum is a species of flowering plant in the carrot family known by the common names beethistle and jointed coyote thistle. This plant is native to the northwestern United States from California to Idaho, where it is a plant of marshes and riverbanks. This is a sturdy, branching perennial herb with rounded, naked stems reaching maximum heights over one meter. It has a few sparse sharply serrated leaves at nodes and branching points along its stem. Atop the stem is the rounded to egg-shaped flower head, which looks superficially like that of a thistle, mainly due to its spikiness and lavender color. It is fringed with up to 17 spiny, toothed, pointed bracts, each up to about two centimeters long. Each flower head is packed full of small lavender flowers.
Euphorbia spathulata is a species of spurge known by the common names warty spurge and roughpod spurge.
Onopordum tauricum, the Taurian thistle or bull cottonthistle, is a species of thistle. It is native to Eurasia and is known in Australia and the western United States as an introduced species. It easily becomes a noxious weed, similar to its relative, Onopordum acanthium.
Heterocodon is a monotypic genus of plants in the bellflower family containing the single species Heterocodon rariflorum, which is known by the common names rareflower heterocodon and western pearlflower. It is native to western North America from British Columbia to California to Colorado, where it emerges during the spring in wet areas such as meadows. This is an annual herb producing a very thin, erect stem to 30 centimeters in maximum height. It branches few times if at all and is dark green to reddish in color. Leaves are occasional along the stem and are heart-shaped to rounded with a toothed edge. Also at occasions along the stem are the flowers, which emerge from a base of toothed or spiny leaflike sepals a few millimeters long. The corolla of the flower is a cylindrical tube 3 to 5 millimeters long, blue or lavender with darker veining and a lighter throat, and spreading into triangular lobes at the mouth.
Lepidium nitidum, known by the common name shining pepperweed, is a species of flowering plant in the mustard family.
Ceanothus spinosus, with the common names greenbark and redheart, is a species of Ceanothus. It is native to southern California and northern Baja California, where it grows in the scrub and chaparral of the coastal mountain ranges.
Amaranthus watsonii is a species of amaranth known by the common name Watson's amaranth. It is native to the southwestern United States and northern Mexico, where it grows in sandy places such as deserts and beaches, and disturbed areas. It is also known as a rare introduced species in parts of Europe. This is an erect annual herb producing a glandular hairy stem to a maximum height of about a meter. The leaves are generally oval-shaped and up to 8 centimeters long, with a petiole of up to 9 centimeters. The species is dioecious, with male and female individuals producing different types of flowers. The inflorescence is a long spike cluster of flowers interspersed with spiny green glandular bracts. The fruit is a smooth capsule about 2 millimeters long that snaps in half to reveal a small shiny reddish black seed.
Ambrosia ilicifolia is a species of ragweed known by the common names hollyleaf burr ragweed and hollyleaf bursage.
Atriplex parryi is a species of saltbush known by the common name Parry's saltbush. It is native to the deserts and plateaus of eastern California and western Nevada.
Clarkia exilis is a small herbaceous annual plant of western North America. It is an uncommon species in the evening primrose family known by the common names Kern River clarkia and slender clarkia.
Eryngium racemosum is a rare species of flowering plant in the family Apiaceae known by the common name delta eryngo, or delta button celery.
Eryngium vaseyi is a species of flowering plant in the family Apiaceae known by the common name coyotethistle. It is endemic to California, where it is known from vernal pools and similar wet habitat in the Central Valley and certain areas of the Central Coast Ranges and southern California coast. This is a decumbent to upright perennial herb with spreading branches up to half a meter long. The lance-shaped to oblong leaves may be up to 24 centimeters long. The edges are deeply cut into narrow, sharp-pointed lobes. The inflorescence is an array of somewhat rounded flower heads surrounded by several narrow, pointed bracts with spiny edges. The head blooms in whitish petals.
Oxytheca perfoliata is a species of flowering plant in the buckwheat family known by the common names round-leaf puncturebract and roundleaf oxytheca. It is native to the southwestern United States, where it is a common plant of the deserts and some woodland and valley areas. It is an annual herb producing a leafless stem up to about 20 centimeters in maximum height in the spring; during the winter the plant is a small rosette of oblong or spoon-shaped leaves a few centimeters wide. The plant is red-veined green, or often brown to maroon or magenta in color. The inflorescence atop the stem is punctuated by nodes at which the bracts are fused to form a cup or band up to about 2.5 centimeters wide. At the end of each branching of the stem is a similar cup of bracts partially fused around a cluster of flowers. The bracts are tipped in spinelike awns. The flowers are white to yellow-green and hairy in texture.
Grindelia ciliata is a species of flowering plant in the family Asteraceae known by the common names Spanish gold, goldenweed, and waxed goldenweed.
Pyrrocoma carthamoides is a species of flowering plant in the family Asteraceae known by the common name largeflower goldenweed. It is native to western North America from British Columbia to northeastern California to Wyoming, where it is known from grassland, woodlands, forests, barren areas, and other habitat. It is a perennial herb growing from a taproot and producing one or more stems to about half a meter in maximum length, the stems reddish-green and leafy. The largest leaves are at the base of the stem, measuring up to 20 centimeters long, lance-shaped with spiny sawtoothed edges. Leaves higher on the stem are smaller and hairier. The inflorescence is a single flower head or a cluster of up to four. Each bell-shaped head is lined with phyllaries each up to 2 centimeters long. It has many yellow disc florets surrounded by a fringe of yellow ray florets up to 7 millimeters long; ray florets are occasionally absent. The fruit is an achene which may be well over a centimeter in length including its pappus.
Streptanthus fenestratus is an uncommon species of flowering plant in the mustard family known by the common name Tehipite Valley jewelflower.
Frasera albicaulis is a species of flowering plant in the gentian family known by the common name whitestem frasera. It is native to the northwestern United States, where it grows in open areas in mountain habitat. It is a perennial herb growing from a woody base surrounded by rosettes of leaves, its stem growing 10 to 70 centimeters tall. The leaves are green with white margins. The basal leaves are lance-shaped, up to 30 centimeters long, and borne on petioles. Leaves higher on the stem are smaller and narrower and are oppositely arranged. The inflorescence is a dense panicle atop the stem, sometimes interrupted into a series of clusters of flowers. Each flower has a calyx of four pointed sepals and a corolla of four pointed lobes each one half to one centimeter long. The corolla is pale greenish white to light blue to purple, often dotted, streaked, or veined with darker blue. There are four stamens tipped with large anthers and a central ovary.
Xanthium spinosum is a species of flowering plant in the aster family known by many common names, including spiny cocklebur, prickly burweed and Bathurst burr. This species is part of the genus Xanthium that encompasses 25 different species of flowering plants of the daisy family, Asteraceae, and sunflower tribe.
Cirsium parryi, or Parry's thistle, is a species of North American flowering plants in the aster family. It is native to the southwestern United States, where it has been found in Colorado, Arizona, and New Mexico.
