Sereno Watson

Picea breweriana, known as Brewer's spruce, Brewer spruce, Brewer's weeping spruce, or weeping spruce, is a species of spruce native to western North America, where it is one of the rarest on the continent. The specific epithet breweriana is in honor of the American botanist William Henry Brewer.

Amaranthus blitoides, commonly called mat amaranth, prostrate pigweed, procumbent pigweed, prostrate amaranth, or matweed, is a glabrous annual plants species. It usually grows up to 0.6 m, though it may grow up to 1 m (3 feet). It flowers in the summer to fall. It is believed to have been a native of the central and possibly eastern United States, but it has naturalized in almost all of temperate North America. It has also naturalized in South America and Eurasia. Some authorities list it as an invasive species.

Populus fremontii, commonly known as Frémont's cottonwood, is a cottonwood native to riparian zones of the Southwestern United States and northern through central Mexico. It is one of three species in Populus sect. Aigeiros. The tree was named after 19th-century American explorer and pathfinder John C. Frémont.

Amaranthus powellii is a species of amaranth known by the common names Powell's amaranth and green amaranth. It is native to the southwestern United States and northern Mexico, but it is common throughout most of the rest of the temperate Americas as a naturalized species. It has also been introduced to other continents, including Australia and Europe.

Hesperocyparis guadalupensis, commonly known as Guadalupe cypress, is a species of western cypress from Guadalupe Island in the Pacific Ocean off the western coast of Mexico's Baja Peninsula. It was previously known as Cupressus guadalupensis until 2009. It is a medium-sized tree with fine green to blue-green foliage. In its native habitat it depends on water from the fogs that envelop high ground in the northern half of the island. It became an endangered species due to feral goats living on Guadalupe Island that – for more than a century – prevented new trees from growing. In 2005 the goats

Amaranthus palmeri is a species of edible flowering plant in the amaranth genus. It has several common names, including carelessweed, dioecious amaranth, Palmer's amaranth, Palmer amaranth, and Palmer's pigweed. It is native to most of the southern half of North America. Populations in the eastern United States are probably naturalized. It has also been introduced to Europe, Australia, and other areas. The plant is fast-growing and highly competitive.

Brahea armata, commonly known as the blue fan palm, blue hesper palm or Mexican blue palm, is a flowering plant in the family Arecaceae, native to Baja California, Mexico. Outside its natural range, it is often planted as an ornamental, valued for its striking grey-blue fronds.

Nicotiana attenuata is a species of wild tobacco known by the common name coyote tobacco. It is native to western North America from British Columbia to Texas and northern Mexico, where it grows in many types of habitat. It is a glandular and sparsely hairy annual herb exceeding a meter in maximum height. The leaf blades may be 10 centimetres (4 in) long, the lower ones oval and the upper narrower in shape, and are borne on petioles. The inflorescence bears several flowers with pinkish or greenish white tubular throats 2 to 3 centimetres (4⁄5 to 1+1⁄5 in) long, their bases enclosed in pointed

Juglans californica, the California black walnut, also called the California walnut, or the Southern California black walnut, is a large shrub or small tree (about 20–49 feet (6.1–14.9 m)) of the walnut family, Juglandaceae, endemic to the Central Valley and the Coast Range valleys from Northern to Southern California.

Aralia californica, known by the common name elk clover though not actually a clover, is a large herb in the family Araliaceae, the only member of the ginseng family native to California and southwestern Oregon. It is also called California aralia and California spikenard.

Platanus wrightii, the Arizona sycamore, is a sycamore tree native to Arizona and New Mexico with its range extending south into the Mexican states of Sonora, Chihuahua, and Sinaloa. The tree is a large deciduous tree, growing up to 82 ft (25 m).

Carex heteroneura is a species of sedge known by the common name different-nerve sedge. It is native to western Canada and the western United States, where it grows in moist mountain habitat such as forests and meadows.

Astragalus acutirostris is a species of milkvetch known by the common name sharpkeel milkvetch. It is native to the Mojave Desert and surroundings of California, Nevada, and Arizona, where it grows in dry, sandy, gravelly areas.

Allium nevadense is a species of wild onion known by the common name Nevada onion. It is native to the western United States where it grows in sand and rocky soil at elevations of 1400–1700 m. The species is widespread in Utah, Nevada and southern Idaho, and has been reported also from southeastern California (Inyo and San Bernardino Counties), northwestern Arizona (Mohave and Cochise Counties), western and central Colorado (Moffat, Garfield, Mesa and Boulder Counties) and eastern Oregon (Harney and Malheur Counties). The Nevada onion grows from a brown or gray bulb one to one and a half

Ageratella is a genus of flowering plants in the family Asteraceae. Species include: Ageratella microphylla (Sch.Bip.) A.Gray ex S.Watson Ageratella palmeri (A.Gray) B.L.Rob.

Nolina parryi (Parry's beargrass, Parry nolina, or giant nolina) is a flowering plant that is native to Baja California, southern California and Arizona.

Nolina microcarpa is a species of flowering plant in the asparagus family known by the common names sacahuista and palmilla. Like other species of Nolina, it may be called beargrass. It is native to northern Mexico and the southwestern United States in Arizona and New Mexico. It does occur in the southwestern corner of Utah, where it has a limited distribution on Navajo Sandstone, but reports of it occurring in Texas may be in error. Sacahuista is variable in appearance. In general it is a large plant that grows in clumps up to two meters wide. It produces a rosette of many narrow leaves each

Nitrophila is a small genus of flowering plants in the amaranth family sometimes known by the common name niterworts. The genus name is Greek for "soda-loving", as the plant grows in alkaline or salty soils, such as those rich in borax. These are rhizomatous perennials with fleshy foliage that helps them conserve water in environments high in mineral salts. The compact, papery flowers grow in the axils of the plant where the leaves join the branches. The fruit is a utricle which contains shiny black seeds. Nitrophila species are found in temperate regions of the Americas.

Lilium grayi (Gray's lily, orange bell lily, Roan lily) is a perennial plant that is endemic to the eastern US states of North Carolina, Virginia, and Tennessee, growing in moist, acid soil in the Appalachian Mountains on higher elevation meadows, bogs, and seeps. The plant was introduced to Royal Botanic Gardens, Kew in 1890 and was featured in the Kew Bulletin in 1892.

Hemiphylacus is a genus of flowering plants endemic to Mexico. In the APG III classification system, it is placed in the family Asparagaceae, subfamily Asparagoideae (formerly the family Asparagaceae sensu stricto). Species: Hemiphylacus alatostylus L.Hern. - Guanajuto, Querétaro, San Luis Potosí Hemiphylacus hintoniorum L.Hern. - Nuevo León Hemiphylacus latifolius S.Watson - Coahuila Hemiphylacus mahindae L.Hern. - Oaxaca, Puebla Hemiphylacus novogalicianus L.Hern. - Aguascalientes

Ephedra aspera is a species of Ephedra known by the common names rough jointfir, boundary ephedra, and pitamoreal. It is native to the southwestern United States from California to Texas and parts of northern Mexico as far south as Zacatecas. It is a resident of varied woodland and scrub plant communities.

Brahea edulis, the Guadalupe palm or palma de Guadalupe, is a palm endemic to Guadalupe Island, Mexico, although a few stands have been planted elsewhere. It is a fan palm which grows 4.50 to 13 metres (15 to 43 ft) tall. It grows on the island between 400 and 1,000 metres (1,300 and 3,300 ft) above mean sea level (ASL), with this altitudinal zonation producing one of the few fog oases present in North America.

Allium lemmonii is a species of wild onion known by the common name Lemmon's onion, named for botanist John Gill Lemmon (1831–1908). It is native to the western United States, at elevations of 1200–1900 m in the Great Basin of Utah, Nevada, northern and eastern California, eastern Oregon, southwestern Idaho. Lemmon's onion grows from a bulb one and a half to two centimeters wide and has a short, flattened stem up to 20 cm tall, which is thin along the edges. Atop the stem is an inflorescence of 10 to 40 bell-shaped flowers, which may be white to pink. The stamens may be purple or yellow;

Allium lacunosum is a species of wild onion known by the common name pitted onion. It is endemic to California, where it is a common member of the flora in many types of habitat, from bayside to mountain to desert.

Allium brandegeei, also known by its common name, Brandegee’s Onion, is a plant species native to the western United States. It has been reported from western Colorado, Utah, Idaho, eastern Oregon, Park County, Montana and Elko County, Nevada. Allium brandegeei grows in sandy, rocky soil at elevations of 1,200–3,300 metres (3,900–10,800 ft). One plant produces 1-5 round to egg-shaped bulbs up to 1.5 centimetres (0.59 in) in diameter. Flowers are bell-shaped, up 8 millimetres (0.31 in) long; tepals white with green or purple midvein.

Allium atrorubens is a species of wild onion known by the common name dark red onion. This plant is native to the southwestern United States where it grows in the sandy soils of the Mojave Desert, the Great Basin and higher-elevation deserts in Nevada, eastern California (San Bernardino, Kern, Mono, Inyo and Lassen Counties) southwestern Utah (Kane, Millard and Beaver Counties), northwestern Arizona (Mohave and Coconino Counties). Allium atrorubens grows from a reddish-brown bulb 1–1.5 cm (3⁄8–5⁄8 in) across. The stem is short and is surrounded by few coiled tubular leaves. Atop the stem is

Sedum palmeri is a species of stonecrop from Mexico. It is a highly variable species with multiple branching stems and rosettes of thick, spoon-shaped, grey-green leaves with pointed tips. It is widely grown as an ornamental plant, especially in the Mediterranean region.

Nolina texana, the Texas sacahuiste or Texas beargrass, is a plant in the asparagus family that resembles a large clump of grass. It grows in the south central United States and Northern Mexico. They are sometimes grown as a garden plant in xeriscape or native plant gardens.

Nolina bigelovii (Bigelow's nolina or beargrass) is a flowering plant native to the Southwestern United States, California, and northwest Mexico. It grows in the driest desert areas and at elevations up to 1,500 m (4,900 ft) .

Hastingsia is a small genus of flowering plants in the family Asparagaceae, subfamily Agavoideae, known generally as rushlilies. These are small perennial herbs endemic to serpentine soils of the Siskiyou-Klamath region in northern California and SW Oregon in the United States. They reach heights between 25 and 90 centimeters and have long linear leaves and racemes of small white flowers. Species: Hastingsia alba (Durand) S.Watson - white rushlily - California and Oregon Hastingsia atropurpurea Becking - Oregon Hastingsia bracteosa S.Watson - largeflower rushlily - Oregon Hastingsia