Arctostaphylos pungens (pointleaf manzanita) ( ) Ericaceae This evergreen shrub extends from the Transverse and Peninsular ranges of southern California to the mountains of Arizona, New Mexico, and Texas into northern Mexico. This species is easily recognized by its vertical leaf orientation, sharp pointed leaf tip, and shiny red bark. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

 Euphorbia micromera (desert spurge) ( ) Euphorbiaceae Our C₄ herbaceous desert flora contains 16 native species of spurge ( Euphorbia ). These prostrate or low growing annuals and herbaceous perennials that flower almost any month of the year. Most have broad ranges, extending well outside of our desert region with several non-native species also widely naturalized. One of the distinctive features of the spurges is the milky sap contained in their stems. What appears to be a single flower in spurges is instead a cup-like structure called a  cyathium  that holds a central female flower surrounded by several male flowers. The structures that look like petals are extensions of the cyathium. Desert spurge is a common prostrate annual. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Euphorbia albomarginata (rattlesnake weed) ( ) Euphorbiaceae Our C₄ herbaceous desert flora contains 16 native species of spurge ( Euphorbia ). These prostrate or low growing annuals and herbaceous perennials that flower almost any month of the year. Most have broad ranges, extending well outside of our desert region with several non-native species also widely naturalized. One of the distinctive features of the spurges is the milky sap contained in their stems. What appears to be a single flower in spurges is instead a cup-like structure called a cyathium that holds a central female flower surrounded by several male flowers. The structures that look like petals are extensions of the cyathium. Rattlesnake weed is a widespread, prostrate perennial whose common name arises from its use to treat rattlesnake bites. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Proboscidea althaeifolia (devil's claw, unicorn plant) ( ) Martyniaceae Among our showiest desert annuals, but relatively uncommon is devil's claw. This unusual member of the unicorn-plant family also utilizes C₄ metabolism and thus summer flowering. Devil's claw is a brilliant, yellow-flowered perennial. It has a sprawling growth form with large, moist, and sticky-lobed leaves. The large bilaterally symmetrical flowers, up to 1½ inch across, look like those of jacaranda and other flowers in the related bignon family ( Bignoniaceae ). It is a perennial with a stout tap root that prefers dunes. The origin of the rather sinister name devil's claw is because of the long, woody capsules, up to 3-4 inches in length, which split open at one end to form a pair of curved claws. These claws readily cling to the hooves of grazing animals, or your shoes if you are not watching where you step. Since these claws don't fit the hooves of native grazing animals, scientists have s

  Cylindropuntia fulgida ( ) ( ) Cactaceae Hikers swear that the plants reach out and grab boots and pant legs. But in fact the spines are so strong that even the slightest grip is enough to cause one segment of the plant to break away. Don't try pulling it out; it will only stick to your hand. Experienced travelers carry a comb and use it to brush the plant away in one swift, painful motion. "Wicked Plants, Amy Stewart."

  Cylindropuntia bigelovii ( ) ( ) Cactaceae Hikers swear that the plants reach out and grab boots and pant legs. But in fact the spines are so strong that even the slightest grip is enough to cause one segment of the plant to break away. Don't try pulling it out; it will only stick to your hand. Experienced travelers carry a comb and use it to brush the plant away in one swift, painful motion. "Wicked Plants, Amy Stewart."

Quercus lobata (valley oak) ( ) Fagaceae Many oak trees host species of wasps, but California's valley oak is one of the best-known and most hospitable of all the oaks. The process begins when a wasp lays an egg on an oak leaf. The plant cells start multiplying at an unusually high rate, forming a kind of protective cocoon called a gall. Eventually the egg hatches into a larva, and the gall, which can get to the size of a baseball, becomes a home to the larva and also gives in something to eat. The larvae emerge as full-grown wasps. One species of wasp causes the valley oak to form small galls that drop off the tree. The galls can jump around for a few days as the wasp inside tries to break free. earning them the name "jumping oak galls". "Wicked Plants, Amy Stewart."  

  Allionia incarnata (windmills) ( ) Nyctaginaceae Windmills is an annual or short-lived perennial with slender, glandular stems that trail along the ground. What appears to be a single, radial symmetrical magenta-colored flower are actually clusters of three bilaterally symmetrical flowers growing together. Windmills favor sandy sols in creosote bush scrub across the southern Mojave and Sonoran deserts. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Boerhavia triquetra (slender spiderling) ( ) Nyctaginaceae A family of C₄ annuals is the four-o'clock family. Although most genera of the Nyctaginaceae use typical C₃ photosynthetic systems, there are two desert genera with C₄ metabolism. The more common group is the spiderlings, with five desert species. All regional spiderling species have tiny. pale pink to white bell-shaped flowers no more than 1/8 inch in length, which may be present from September to December. Slender spiderling is the most common species. It is an erect annual, up to 2 feet in height, with sticky areas along the slender stems between nodes. It is found widely and abundantly in creosote bush and Joshua tree woodlands of the southern Mojave and Sonoran deserts. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Pectis papposa (chinchweed) ( ) Asteraceae Chinchweed, one of the few members of th e Asteraceae with C₄ metabolism. In some years, with widespread summer storms, chinchweed blooms in such numbers it paints yellow across creosote bush scrub and Joshua tree woodlands in the central and eastern Mojave deserts. Chinchweed has a low spreading or mounding growth form and small, narrow leaves with pungent, spicy-smelling glands. " California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Hesperocallis undulata (desert lily) (lirio del desierto)  Asparagaceae Our most notable geophyte is the desert lily, an unusual endemic found on sandy flats and dunes below 2.500 feet in the western and southern Mojave desert and adjacent areas of the Sonoran Desert. A good place to see this species is at the Kelso Dunes in the eastern Mojave Desert. Desert lily arises from a large bulb, with a basal rosette of bluish-green leaves, 10-20 inches in length, with a distinctive wavy margin. These rosettes are distinct all other desert geophytes. The single flowering stalk reaches anywhere from 1-6 feet in height depending on growing conditions, and beats clusters of large trumpet-shaped flowers that resemble small Easter lilies. The flowers have a strong, sweet fragrance that attracts hawk moths-the primary pollinators. Desert lily was once included in the lily family but is now placed in the Agave subfamily within the asparagus family.   "California Desert Plants, Philip J Rundel,

  Asclepias subulata (rush milkweed) ( ) Apocynaceae The milky sap of the tissues of milkweed contains toxic compounds called cardiac glycosides. Monarch butterflies that feed on these tissues sequester these toxins in their bodies, making them unpalatable to birds. In addition to milky sap, a feature of milkweed is the large pods, usually several inches in length, that split open when mature and release large numbers of wind-dispersed seeds with hairy plumes. Rush milkweed is a tall perennial, reaching up to 3 feet in height. Its common name comes from upright stems tat are leafless for most of the year. It occurs in dry washes at low elevations in the eastern Mojave and Sonoran desert.   "California Desert Plants, Philip J Rundel, Robert W Gustafson, Michael E Kauffmann."

  Mentzelia involucrata (sand blazing star) ( ) Loasaceae Sand blazing star is a branched annual with large, funnel-shaped white-to pale-yellow flowers that an reach more than 2 inches in width. It has large, highly toothed basal leaves and small linear stem leaves. It occurs in a variety of habitats including creosote bush scrub and desert washes, but is most common in the southern Mojave and Sonoran deserts. "California Desert Plants, Philip J Rundel, Robert W Gustafson, Michael E Kauffmann."

  Chorizanthe rigida (devi's spineflower) ( ) Polygonaceae Devil's spineflower is a smaller erect annual with broadly elliptical leaves forming a basal rosette and along the stem. Secondary leaf nodes develop into hard spines as the plant develops, giving it s thorny appearance. Devil's spineflower commonly occurs on desert pavement adjacent to creosote bush scrub in both the Mojave and Sonoran deserts. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Eriogonum deflexum (flat-topped buckwheat) ( ) Polygonaceae Flat-topped buckwheat is a tall annual, up to 2 feet in height. It has an erect flowering stalk arising from a basal rosette of small, kidney-shaped leaves. The tiny white-to-pink-flowers are borne in a flat-topped crown, giving rise to the common name. It occurs widely on sandy and gravelly flats of creosote bush scrub and Joshua tree woodlands. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Dithyrea californica (California spectacle-pod) ( ) Brassicaceae California spectacle-pod is a small annual whose common name comes from the appearance of its fruits with two flat rounded lobes that look like eyeglasses. Its trailing stems, that curve upward with clusters of small white flowers at their tips, are a unique growth form. California spectacle-pod is found in sandy soils and washes of creosote bush scrub across both California deserts. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Oenothera primiveris  (yellow evening primrose) ( ) Onagraceae Yellow evening primrose is a prostrate species with bright yellow flowers that might be confued at first with Camissonia . The four-parted stigma is the distinguishing trait that separates these genera. Yellow evening primrose has a basal rosette of glandular leaves that are strongly toothed to pinnately divided into broad lobes. "Califorina Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Oenothera californica (California evening primrose) ( ) Onagraceae California evening primrose is a widespread and variable perennial with a range extending across much of the coastal foothills and desert areas of California in a range of habitats. It begins life as a rosette plant but gradually elongates a peeling leafy stem that trails for 30 inches or more along the ground. The large white flowers open at night. "Califorina Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Chylismia claviformis (Brown-eyed primrose) ( ) Onagraceae Brown-eyed primrose is a variable species with flowers that range from bright yellow to white in color. This is a common species with a widespread range in sandy washes and slopes of creosote bush scrub and Joshua tree woodland, as well as widely in western North America. Brown-eyed primrose is an erect species ranging in height from just a few inches to 24 inches depending on rainfall. Its common name comes from the presence of large brown or purple spots at the base of each petal, giving the flower a dark center. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Chylismia arenaria (sand evning primrose) ( ) Onagraceae Sand evening primrose is a tall annual or bushy perennial up to more than 3 feet in height, with yellow flowers that open at dusk. This species is found in sandy washes and rocky slopes of creosote bush scrub in the Sonoran Desert. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Onagraceae The evening primroses, and related species of Onagraceae, are one of the primary food plants of the sphinx moth. Years with abundant evening primrose blooms are correlated with millions of sphinx moth larvae feeding on these plants. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Castilleja exserta (purple owl's clover) ( ) Orobanchaceae Purple owl's clover is a California grassland species that extends its range into the wester Mojave Desert. This is a showy annual species with bright magenta flowers with white or yellow markings on the petals. In wet years it often occurs in dense populations that color the landscape. Like other root parasites it appears as any other plant, with foliage indicating the presence of chlorophyll and active photosynthesis. However they supplement nutrient and carbohydrate supplies with parasitic roots that tap the below-ground tissues of other species. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Phacelia crenulata (Notch-leaved phacelia) (  ) Hydrophyllaceae There are two species of phacelia that are notable for their foul smell. Notch-leaved phacelia is an erect but little branched annual with thick and densely glandular stems. Its violet-purple flowers, with a touch of white at the petal base, highlight dark green leaves that are highly dissected into leaflets lobes with scalloped margins. The truly distinguishing feature of this plant is the unpleasant odor that has been described as a "skunk in syrup". It is widespread across creosote bush scrub up into pinyon-juniper woodlands and beyond across the western United States. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Phacelia distans (lace-leaf phacelia) ( ) Hydrophyllaceae Perhaps our most common species is lace-leaf phacelia, whose common name describes the highly dissected fern-like leaves. It displays spikes of relatively small (1⁄4-1⁄2 inch) pale blue to lavender flowers. Lace-leaf phacelia is a widespread and abundant on clayey and gravelly flats and slopes where it often blooms even in relatively dry years below the protective canopy of creosote bush. It has a broad distribution not only in our deserts but through our Mediterranean-type shrublands. "California Native Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Boraginaceae Phacelias and several related genera form one of the most familiar groups of desert annuals. Desert Phacelia species produce some of the most spectacular and colorful display in years with good rainfall, covering broad areas of flats and bajada slopes with masses of blue or purple flowers. Unlike some species of Asteraceae and Onagraceae  where a single species covers broad areas, flowering displays of pahcelias typically include multiple species. Phacelia is one of the largest genera in California, with 93 species with 34 of these in our deserts. A characteristic of the genus is the presene of dense glandular hairs on the stems and foliage. A significant number of people are sensitive to the glandular secretions of phacelia and develop a rash similar to that of poison oak. Most of our desert phacelias are erect annuals with distinctly divided basal leaflets and stem leaves that are deeply lobed. "California Native Plants, Philip W Rundel, Robert J Gustafson, Michae

  Astragalus Fabaceae The common names locoweed, rattleweed, and milkvetch all apply to members of the diverse genus Astragalus, with more than 2,000 species worldwide. With 94 species in California and 34 in our desert regions, it is one of the most species-rich genera in California. Although a few species of Astragalus are distinctive, most are difficult to identify without examining both flowers and fruits. Our flora includes both annual and perennial species, with most sharing a mat-like growth form and small pinnate leaflets. There are exceptions, however, with tall, relatively upright species. A characteristic feature of many species, and he source of the name rattleweed, comes from the inflated seed pods. When mature, pods rattle hen blown by the wind. The name locoweed comes from the toxic accumulation of selenium in many species that poison cattle and cause them to behave strangely when eaten. "California Native Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauf

Marina parryi (Parry dalea) ( ) Fabaceae The Parry dalea is a slender perennial herb with long hairy stems, reaching to 30 inches in height, with small, sparse, resin-dotted leaves. It is found across our low elevation deserts at elevations below 2,000 feet on rocky slopes or open washes. The small purple blue flowers are clustered in dense spikes.  "California Native Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."   

  Dalea mollis (hairy prairie clover) ( ) Fabaceae The hairy prairie clover is common in the California desert areas and it is similar to silky dalea ( Dallea mollisima ) but with leaflet margins that are entire and flat, as opposed to silky dalea which has leaflet margins that are shallowly lobed or wavy. Hairy prairie clover favor sandier and lower elevation habitats that silky dalea. Although both species are relatively uncommon in dry years, they germinate and densely cover desert flats in years with abundant rainfall and are important for the nitrogen they fix. "California Native Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Dalea mollisima (silky dalea) ( ) Fabaceae The most common herbaceous legume in the desert flora of California is silky dalea which occurs widely across our Sonoran Desert region on coarse or gravelly flats and washes of creosote bush scrub at elevations below 3,000 feet. This mat-forming species sprawls over diameters of up to 12 inches, with blue-gray pinnately compound leaves dotted with black glands and covered with fine, soft hairs. The small pea flowers are pink to white in color and produced on short dense spikes. "California Native Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Lupinus arizonicus (Arizona lupine) ( ) Fabaceae Arizona lupine is one of the most common and conspicuous desert lupines when it blooms in sandy washes and open creosote bush scrub below 3,000 feet in the Mojave and Sonoran deserts. Its is particularly abundant in spring along roadsides. Although an annual, Arizona lupine is a robust plant that is typically 1-2 feet in height. Its stems and the underside of its green leaflets have long, spreading hairs. The purple flowers have a yellowish spot on each of the banners, which are the two petals that spread horizontally. "California Native Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

 Argemone munita (chicalote) ( ) Papaveraceae Chicalote is characterized by spinier leaves than Argemone corymbosa and yellow sap. It has a broad elevation range that extends to forest habitats over the Great Basin and beyond. It has a large "fried egg" flower with white petals and clustered yellow stamens at the center. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Eschscholzia californica (California poppy) (amapola de California) Papaveraceae The most prominent of our desert poppies, and our state flower, is the familiar California poppy. California poppies occur widely over grasslands and oak woodlands throughout California but are also notably abundant in the western Mojave Desert. Their orange to yellow flowers often color the expanses of the landscape in favorable years, growing both as an annual or perennial. The Antelope Valley Poppy Preserve, near Lancaster, is famous for its spring displays of poppies. Interestingly, California poppies thrive with disturbance and regular grazing promotes the dominance of this species. The odd generic name commemorates a Russian naturalist and surgeon, Dr. Johann Friedrich Gustav von Eschscholtz who first collected this California poppy near San Francsico in 1815. Somehow the "t" in his name was lost in translation. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael

Chaenactis fremontii (desert pincushion) ( ) Asteraceae A common species with white discoid flowers is desert pincushion. It is one of eight related species of pincushion in the California deserts. Most of these are annuals, although there are two species of perennial pincushion in the mountains of the eastern an northern Mojave Desert. Desert pincushion is an erect, branched annual that begins life with a basal rosette of leaves, which senesces as the stems mature and flowering begins. The smooth stems lack hairs and produce single or multiple flower heads composed entirely of disk flowers. In favorable years, desert pincushion is found blooming in massive numbers across open sandy flats of creosote bush scrub and Joshua tree woodlands. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Perityle emoryi (Emory rock daisy) ( ) Asteraceae Emory rock daisy is erect with a bristle, glandular, and hairy stem with broad palmately-lobed leaves. The flowers are typical discoid daisy flowers with a small number of white ray flowers and numerous small yellow disk flowers. Emory rock daisy is a common species across both the Mojave and Sonoran desert at elevations below about 3,000 feet where it favors rocky canyon walls and boulder washes where water collects. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Malacothrix glabrata (desert dandelion) ( ) Asteraceae One annual, capable of coloring large areas sandy flats ad washes, as well as disturbed roadsides is desert dandelion. This is the most common among a group of six desert dandelion species that share the traits of milky sap and ligulate flower heads. Desert dandelion has a rosette of basal leaves that forms early and then often becomes withered by the time that flowering occurs. Flowering stalks vary in height from a few inches to 16 inches in a year with good rains. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Baileya pauciradiata (lax flower) ( ) Asteraceae Lax flower is an annual with smaller flower heads with fewer disk flowers than desert marigold, foliage is covered by soft woolly hairs. The basal leaves of lax flower wither before the flowers reach maturity. Lax flower is limited to elevations below about 3.500 feet in the eastern Mojave and Sonoran deserts where it favors sandy soils and dunes. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Baileya multiradiata (desert marigold) ( ) Asteraceae Desert marigold is a short-lived perennial that reaches 10-20 inches in height, with white-woolly stems and gray-green pinnately-lobed leaves arrayed near the base of the plant. It extends leafless flowering stalks with large and spectacular flower heads. Desert marigold is common in sandy and rocky flats on bajada slopes of creosote bush scrub and Joshua tree woodland in the eastern Mojave Desert. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Geraea canescens (desert suflower) ( ) Asteraceae Desert sunflower is a close relative of Encelia that can provide massive displays of yellow across the central and eastern Mojave Desert. Typically this species covers sandy flats under creosote bush scrub at elevations below about 4,000 feet. Its leaves and stems are covered with soft hairs and it displays broad radiate flower heads about ¾ inches in diameter. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Palafoxia arida ( ) ( ) Asteraceae Palafoxia arida var. gigantea (Spanish needle) ( ) Giant Spanish needle is a striking pink-flowered member of the sunflower family. The typical form of this species is a widespread plant in sandy places throughout the California deserts, but this large and often perennial variety reaches as much as 6 feet high-three times the height of the typical form of the species. As is the case with many dune taxa, the seeds of the giant Spanish needle will germinate and emerge from depths much greater than the non-dune variety of Spanish needle. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Helianthus niveus ( ) ( ) Asteraceae Helianthus niveus subsp. tephrodes (Algodones Dunes sunflower) ( ) Algodones Dunes sunflower is an attractive dune plant known in California only from these dunes. This silver-leafed member of the sunflower family inhabits the interior portions of the dunes at the bases along the sides of large dunes. It grows to more than 2 feet in height which is taller than its cousin Helianthus niveus subsp. canescens- widespread on dunes and low sandy places across the Sonoran Desert. Extremely tolerant of moving sand. Algodones Dunes sunflower grows rapidly to avoid being buried. Interestingly, this sunflower has two distinct seasons of flowering-one from March to May and another from October to January- when it produces bright yellow daisy-like flower heads. It has a CNPS Rare Plant Rank 1B: rare, threatened, or endangered in California and elsewhere. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Astragalus magdalenae ( ) ( ) Fabaceae Astragalus magdalenae var. peirsonii (Perison's milkvetch) ( ) One of the rare endemic plants of the dune habitats is Peirson's milkvetch, a silvery, perennial member of the pea family. It grows as tall as 2.5 feet and is notable among the many milvetch species for its small leaves. The large seeds of Perison's milkvetch (larger than any other milkvetch) are thought to be an adaptation to life as a dune plant. Large seeds have the carbohydrate resource to germinate and emerge from under several inches of sand, It has a CNPS Rare Plant Rank 1B: rare, threatened, or endangered in California and elsewhere. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Pholisma sonorae (sand food) ( ) Boraginaceae One of the most unusual dune plants of the lower desert is sand food, a bizarre root parasite that erupts with a head of scale-like leaves and flowers from the sand. Most of the tissues of this strange plant lies in a succulent stem that extend as much as 3-6 feet below the sand surface where it attaches to roots of nearby host plants. The common name comes from the fact that the fleshy tissue is eaten raw or roasted by Native American tribes including the Sand Papagos and Cocopas. The flavor o the stems is described as slightly sweet, with the texture of a crisp radish. Because of its limited range in the lower Sonoran Desert and specific habitat requirements it has a CNPS Rare Plant Tank 1B: rare, threatened, or endangered in California and elsewhere. "Califoria Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Dicoria canescens (desert twinbugs) ( ) Asteraceae Annual plants, which must reestablish their populations from seed each yea, would seem to be poorly adapted to surviving in dune habitats. While this is generally true, there are a few annual species that are quite successful on sandy substrates such as dunes. An example of this mode of occurrence is seen in an unusual annual called desert twinbugs which forms thickets of many individuals in the desert sand. Unlike most annuals, it is aided in growth by a strong taproot and reaches heights up tp 2-3 feet. This plant has distinctive long and sharply toothed lower leaves and sharply toothed, contrasted with smaller and rounded upper leaves. Both leaf types are densely covered with white or gray hairs to reflect the sun. Each plant can produce several whitish discoid flower heads which lack ray flowers. These heads often form closely associated pairs, a characteristic which is the origin of "twinbugs". "Califoria Desert P

  Hesperocallis undulata (desert lily) ( ) Asparagaceae Desert lily, one of the few desert bulb plants, is a slender, perennial herb. This widespread species occurs on dunes but is also common on sandy flats and mesas of creosote bus scrub and Joshua tree woodlands of the southern and western Mojave Desert, as well as the lower Sonoran Desert in California. "Califoria Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Abronia villosa (desert sand verbena) (  ) Nyctaginaceae Frequently growing with dune evening primrose is desert sand verbena, an annual plant with beautiful pink to magenta-colored flowers. The many trailing stems of sand verbena grow outward for as much as 2 feet, with thick rounded leaves covered by sticky hairs along their length. This is an easy plant to recognize and perhaps the most photographed of all desert annuals. It is widely distributed in low sandy valleys and edges o dunes in lower elevations of both the Mojave and Sonoran deserts. "Califoria Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Oenothera deltoides (dune evening primrose, birdcage evening primrose) ( ) Onagraceae One of the most spectacular wildflowers of sandy soils and sand dunes throughout the California deserts is dune evening primrose. It has showy, large, and fragrant white flowers that turn pinkish with age. This herbaceous perennial often grows in profusion on lower dune slopes-presenting a spectacular wildflower display. The name evening primrose comes from the temporal pattern where flowers open in the evening for mot pollinators and close again in mid-morning. Other common names for the primrose are desert lantern and birdcage primrose (because of the unusual form of the dried flowering stalk). The flower stalk has radiating branches extending in all directions along the ground. At the end of the spring flowering season, the greenish branches eventually dry and curl up upward toward the central axis. Woody seed capsules that split into our prongs now occupy the positions where the large flowers us

  Croton wigginsii (Wiggin's croton) ( ) Euphorbiaceae The silvery coloration of the stems and leaves in many dune plants is an adaptation to the excessive solar radiation in desert regions. The leaves of some plants have a dense covering of fine hairs that give them their silvery appearance as well as a velvet-like softness. Other plants have tiny plate-like overlapping silvery scales that cover the leaves. Both these leaf surface forms aid plants in reflecting excess solar energy as well as helping control water loss. Wiggin's croton is a common species on the Algodones Dunes, but highly restricted in distribution. It has a CNPS Rare Plant Rank 2B: rare, threatened, or endangered in California; common elsewhere. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Croton californicus (sand croton) ( ) Euphorbiaceae The silvery coloration of the stems and leaves in many dune plants is an adaptation to the excessive solar radiation in desert regions. The leaves of some plants have a dense covering of fine hairs that give them their silvery appearance as well as a velvet-like softness. Other plants have tiny plate-like overlapping silvery scales that cover the leaves. Both these leaf surface forms aid plants in reflecting excess solar energy as well as helping control water loss. An example is seen in sand croton, an undistinguished semi-woody gray shrub 2-3 feet in height. It is a common sandy soil species that grows well in stabilized desert dunes as well as in sandy soils along the coast of southern California. Often individual shrubs collect sand around their base, forming low mounds. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Eriogonum deserticola (dune eriogonum) ( ) Polygonaceae Unstable dune surfaces represent the greatest threat to dune plants. Only species that survive cycles of burial and erosion are successful in such dynamic habitats. One strategy for growing on moving dunes is to have a deep ad extensive root system that can stabilize mounds of sand, thereby limiting erosion. A tolerance of irregular burial by moving sand is seen in dune eriogonum, a long-lived woody shrub primarily restricted in California to Algodones Dunes. Large plants are tolerant of being cyclically buried and uncovered by moving sand, and large  lateral roots that may extend for 10 feet or more. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Atriplex lentiformis (quailbush) ( ) Amaranthaceae Quailbush is commonly associated with mildly alkaline desert washes and wetlands around palm oases, and is often abundant in disturbed sites. It is a large sprawling shrub that is widespread on alkaline soil of the San Joaquin Valley and coastal California. Quailbush lacks spines and the large leaves are ovate to triangular, 0.5-2 inches in width, an with their surface covered by dense gray scales. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffman."

Atriplex polycarpa (allscale, cattle spinach) ( ) Amaranthaceae Allscale is widespread throughout the California desert regions in mildly alkaline flats and playa depressions, often forming the outer-ring of saltbush scrub stands around playas. Unlike the more cold-tolerant shadscale, it does not occur at elevations above 5,000 feet. Alllscale is a good-sized shrub, often reaching 4-6 feet in height, with small and narrowly oblong leaves with a short petiole. Because of its palatability to cattle, it is sometimes called cattle spinach. Although often present in mixed Atriplex stands, allscale may also be found in relatively pure stands. An interesting characteristic of allscale is it has been shown to change from male to female or back in a given flowering year depending on resource availability.   "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Atriplex Chenopodiaceae Large desert playas tend to be defined by vegetation rings that form around their margins, with salinity as the key selecting factor. As you move along the lower bajada slopes or sandy flats approaching a playa, creosote bush typically drops out quite abruptly. This boundary for the creosote closely approximates the geologic lakebed and lies well beyond the existing playa. While residual salinity may be one factor in limiting the occurrence of creosote bush, more important is the fine texture of the lakebed soils which provides poor mixing of soil gases. Below this boundary, creosote bush is replaced by a community called saltbush scrub with a dominance of various species of saltbush. These saltbush habitats typically exhibit loamy soils with low levels o residual salinity originating from evaporation out of the geological lakebed. The saltbushes form the genus Atriplex in the goosefoot family or Chenopodiaceae. Some recent evolutionary studies place this fami

  Typha dominguensis (narrow-leaved cattail) (tule) Typhaceae A group of tall marsh species are the cattails. The most common of these in our desert areas is the narrow-leaved cattail, which is distinguished by a bare area on the flowering stalks separating the male flowers above the female flowers below. It reproduces vegetatively from underground rhizomes. It is able to survive the anaerobic conditions of waterlogged soils by using hollow stems to transport air to the roots. "California Desert Plants, Philp W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Phragmites australis (common reed) ( ) Poaceae Common reed is a robust perennial grass wit ha remarkable range that extends to wetland habitats throughout the world, here common in desert marshes. It reproduces vegetatively from underground rhizomes. It is able to survive the anaerobic conditions of waterlogged soils by using hollow stems to transport air to the roots.  "California Desert Plants, Philp W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Schoenoplectus americanus (bulrush) ( ) Cyperaceae Small wetland pools, with permanent water supplied by a complex hydrologic system of regional aquifers, promote a characteristic plant assemblages dominated by freshwater marsh species more typically encountered in non-arid areas of California and the western United States. The most prominent of these are bulrushes, which reach 5-10 feet or more in height. These members of the sedge family are recognized by the triangular shape of the stem cross-section, a character easily remembered by the mnemonic phrase, "sedges have edges." It reproduces vegetatively from underground rhizomes. It is able to survive the anaerobic conditions of waterlogged soils by using hollow stems to transport air to the roots.  "California Desert Plants, Philp W Rundel, Robert J Gustafson, Michael E Kauffmann."

 Prosopsis pubescens (screwbean mesquite) (mezquite tornillo)  Fabaceae Present in open or continuous stands is screwbean mesquite. known as tornillo in Spanish, which is also geographically widespread but much less common in California. It is easily recognized when fruits are present because of the shape of the pods with a tightly coiled pattern of growth. Screwbean mesquite is generally restricted in California to areas with permanent or semi-permanent groundwater, but generally is not able to root to depths more than about 10-15 feet. "California Desert Plants, Philip W Runder, Robert J Gustafson, Michael E Kauffmann."

  Salix exigua (sandbar willow, coyote willow) (sauce coyote) Salicaceae Sandbar willow is easily distinguished by long, thin, grayish leaves with silky hairs usually well bellow 15-20 feet. Other names for this species include narrow-leaved willow and coyote willow. The latter name derives from the fact that the shade cast by the shrubby growth provides a favored site for coyote dens. These is a common willow at lower desert elevations. Willows lose their leaves during winter months. While it may seem strange to have such moisture-loving species in the desert, the presence of a relatively permanent flow or groundwater pool of available freshwater provides conditions well suited for growth. So long as water is available, high summer temperatures present little or no threat.  "California Desert Plants, Philip W Runder, Robert J Gustafson, Michael E Kauffmann."

  Salix gooddingii  (Goodding's black willow) ( ) Salicaceae Black willow is tree with a prominent main trunk. It has leaves with a similar green color on both surfaces. It can be a large tree and reach heights up to 100 feet. This is a riparian willow that forms riparian thickets. Willows lose their leaves during winter months. While it may seem strange to have such moisture-loving species in the desert, the presence of a relatively permanent flow or groundwater pool of available freshwater provides conditions well suited for growth. So long as water is available, high summer temperatures present little or no threat.   "California Desert Plants, Philip W Runder, Robert J Gustafson, Michael E Kauffmann."

  Salix laevigata (red willow) ( ) Salicaceae Red willow is a tree with a prominent main trunk. It is characterized by leaves that are grayish or gray-white on their lower surface, reaches heights of 20-30 feet or even taller under optimal growing conditions. This is a riparian willow that forms riparian thickets. Willows lose their leaves during winter months. While it may seem strange to have such moisture-loving species in the desert, the presence of a relatively permanent flow or groundwater pool of available freshwater provides conditions well suited for growth. So long as water is available, high summer temperatures present little or no threat.   "California Desert Plants, Philip W Runder, Robert J Gustafson, Michael E Kauffmann."

  Atriplex lentiformis (quailbush, big salt bush) ( ) Amaranthaceae Quailbush is a large shrub that reaches as much as 8-10 feet in height, but with a sprawling growth form that makes it generally much wider than tall. Rather than being exclusively a desert species, quailbush is common in coastal areas of southern California as well. While it is found in alkalines and saline washes and in mixed salt scrub communities around playas, it is widely distributed around the margins of both coastal and desert wetlands. Although it may occasionally occur in sheltered areas at elevations up to 4.500 feet, it is more typical of the lower desert areas below 2,000 feet.   "California Desert Plants, Philip W Runder, Robert J Gustafson, Michael E Kauffmann."

  Washingtonia filifera (California fan palm)( ) Arecaceae The California fan pal is the only palm native to California. It is thought to be an ancient species with a history dating back to the middle Tertiary when it occurred more broadly across coastal and Mojave Desert areas of the state. Today, the natural range of this species is highly localized at scattered desert sites where permanent water exists relatively close to the soil surface. There are approximately 100 palm oases in California, with populations ranging from only a few to hundreds of mature palms. The largest groups of palm oases occur around the Coachella Valley where geologic conditions along the San Andreas fault promote shallow groundwater tables. From this center of distribution, California fan palm extends to the north to Twentynine Palms and the Cottonwood Mountains and south into northern Baja California where it is replaced by the related Mexican fan palm ( Washingtonia robusta ). Although similar in appearanc

  Fouquieria splendens (ocotillo) Fouquieriaceae Ocotillo is an unusual species with a remarkably wide range across the entire Sonoran Desert and into the Chihuahuan Desert. It is one of only a few woody species that naturally occurs in both desert regions. The spiny stems of ocotillo are highly distinctive, giving the appearance of tall wands or carriage whips. Perhaps the most remarkable feature of the ecology of ocotillo is how rapidly it responds to rainfall. For most of the year ocotillo stands leafless, but following a significant rain event it produces new cohort of leaves may remain on the plant for months. Under such conditions, showy red flowers are produced. With less rainfall, the leaves have a relatively short life span; they dry out and are shed within a few weeks. Ocotillo demonstrates remarkable flexibility in its ability to produce as many as five to six times in a season if rains are scattered. At the other extreme, in a dry year, leaf production may not occur. The st

  Bursera microphylla (elephant tree) (torote) Burseraceae  The elephant tree is a squat, stem-succulent tree reaching up to 15 feet in height found in scattered wash habitats of Anza Borrego Desert State Park. The common name comes from the thick trunk and major branches which contain succulent tissues for the storage of water an resemble and elephant's trunk. Peeling back the exfoliating bark reveals a greenish main trunk. These stem tissues maintain low levels of photosynthesis during the dry portions of the year when the plants are leafless, but probably not enough to do more than partially balance the costs of respiration. The drought-deciduous leaves are clustered at the ends of short shoots and contain highly aromatic terpenoids. A puff of these compounds can be seen spraying into the air if one carefully pulls a single leaf from a branch of elephant tree and watches carefully. It has a CNPS Rare Plant Rank 2B: plants rare, threatened or endangered in California and elsewher

  Justicia californica (Beleperone) ( ) Acanthaceae Belperone is a scraggly shrub 2-5 feet in height with gray-green photosynthetic stems that is virtually leafless most of the year. It is frequently found growing in sandy washes of our lower desert areas- and widely throughout the Sonoran Desert outside of California with summer rainfall. Both summer drought and cold temperatures can cause beleperone to lose its leaves. A prominent, tubular red flowers appear in spring and are frequently visited by hummingbirds to harvest the nectar. Beleperone is an outlier of the largely tropical Acanthaceae family, which has extended its range into the low desert region of California.   "California Desert Plants, Philip W Runder, Robert J Gustafson, Michael E Kauffmann."

  Baccharis sarothroides (broom baccharis) ( ) Asteraceae Broom baccharis is a wash species with narrow linear leaves no more than 2 inches in length. It occurs widely across the western Sonoran Desert, as well as extending into coastal areas of southern California. It reaches 12 feet in height. "California Desert Plants, Philip W Runder, Robert J Gustafson, Michael E Kauffmann."

  Bebbia juncea (sweetbush) ( ) Asteraceae Sweetbush is a commonly encountered shrub in wash habitats below 4, 000 feet in both the Mojave and Sonoran Deserts. It is a highly-branched subshrub in the Asteraceae family that reaches up to 4 feet in height. The small linear leaves of sweetbush are oppositely arrayed low on the plant and alternate above; they are only present for a short period of time in the spring and the plant's stems are  the primary photosynthetic organ during the remainder of the year. The pale-yellow flower heads of sweetbush are discoid, as there are no outer flowers with petal-like organs. Sweetbush is a nondescript plant for most of the year when neither leaves nor flowers are present, but it is easily recognized by it sweetly aromatic stems from which it gets its name. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Ambrosia ilicifolia (hollyleaf bursage) ( ) Asteraceae Hollyleaf bursage is limited to sandy washes and rocky canyons in lower elevations of the Sonoran Desert. It has elongated leathery leaves with tothed margins. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Condea emoryi (desert lavender) ( ) Lamiaceae A small number of shrubby wash species exhibit a drought-deciduous behavior by shedding their leaves under summer water stress. Desert lavender is a large shrub found in rocky washes and channels throughout the Sonoran Desert and lower elevation Mojave Desert up to 3,000 feet elevation, and eastward as far as the Chihuahuan Desert. This erect shrub is generally 4-10 feet in height, with simple ovate leaves covered with a dense, white pubescence. The opposite arrangement of the leaves and the sweet fragrance of the foliage help identify desert lavender as a member of the mint family. Like other drought-deciduous shrubs, desert lavender exhibit seasonal leaf dimorphism. The first leaves produced in spring are relatively large and this, with less dense pubescence. As the season progresses and water stress slowly increases, new leaves are increasingly smaller and thicker, with denser pubescence. This seasonal leaf dimorphism allows the plant

Senna covesii (Cove's senna) ( )   Fabaceae Cove's senna is a smaller plant than Senna armata,  but has large, more persistent gray leaves covered by dense white hairs. It also displays stem photosynthesis. Cove's senna is largely restricted to washes in the Sonoran Desert and has a CNPS Rare Plant Rank 2B: plants rare, threatened, or endangered in California and elsewhere. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Hoffmannssegia microphyla (rushpea) ( ) Fabaceae Rushpea inhabits washes and arroyos in the lower Sonoran Desert. The common name of this legume shrub comes from its green, rush-like stems that reach 2-4 feet or more in height. The pinnately divided leaves are short-lived, with a significant amount of the photosynthetic responsibility given to the green stems which can attain high rates of photosynthetic output. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Parkinsonia aculeata (Mexican palo verde) ( ) Fabaceae Mexican palo verde does not occur naturally in California but has been used widely in landscaping and shows the potential to become an invasive in our wash woodland habitats. Mexican palo verde is a large tree up to 40 feet in height. White it has yellowish-green bark on its upper young branches, it lacks a green trunk like our two native palo verde species. The most distinctive trait is its unusual leaves, which are pinnately divided with an exposed central rachis and almost no foliar area. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Parkinsonia microphylla (little-leaf palo verde) ( ) Fabaceae Little-leaf palo verde is a tree up to 20 feet in height that is typical of bajadas slopes. In California it is only found along the Colorado River in San Bernardino County and south to Imperial County near the Mexico border, however it is widespread across the broader Sonoran Desert outside of California. It displays a yellowish-green bark, and it lacks spines and has spine tipped branches with smaller ephemeral leaves that lack a petiole. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

Parkinsonia florida    (blue palo verde) ( ) Fabaceae Blue palo verde is a moderate sized tree reaching up to 25 feet in height. It is common in washes in the lower desert areas of California where it often occurs with desert ironwood. Blue palo verde species of the Coachella Valley and Salton Sea basin, it is also widespread cross the broader Sonoran Desert outside of Califoria. The bark of the blue palo verde is a distinctive blue-green, it has spines at each node and leaves with clear petioles. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

Psorothamnus spinosus (smoke tree) ( ) Fabaceae Smoke tree, which is virtually leafless, displays stems as its primary photosynthetic organs. It is a common and often dominant species in desert washes in reaches up to 25 feet in height, exhibits a dense silvery-gray pubescence that covers its spine-tipped branches, The combination of the gray branches and the leaflessness of these trees gives them a decidedly smoky appearance when viewed from a distance-especially with low sun angles near dawn or dusk. Like other legumes, smoke trees have root nodules with symbiotic nitrogen-fixing bacteria, this clearly helps this species to successfully colonize nutrient-poor soils in desert washes. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Chilopsis linearis (desert-willow) ( ) Fabaceae Desert-willow is our only California member of the tropical bignonia family, the Bignoniaceae. The growth form of desert-willow ranges from a sprawling shrub to a small tree reaching up to 20 feet in height. The name desert-willow comes from the fact that its long and narrow leaves 4-6 inches in length, resemble those of a true willow. This species is largely restricted to low-nutrient gravelly washes in Sonoran Desert areas such as in the Coahella Valley and Anza Borrego Desert State Park-although it extends into scattered areas of the lower Mojave Desert. As with the other species described above, desert-willow loses its leaves for three to four months in winter. Large, showy pink-to whitish-flowers are produced each spring and make desert willow an attractive plant for desert gardens. The fruits of desert-willow are elongate pod-like capsules 4-10 inches in length which enclose flat wind-dispersed seeds with silky hairs tufted at eac

 Olneya tesota (ironwood) (palo fierro) Fabaceae It is a moderate-sized, winter deciduous tree that grows 15-30 feet in height with a spreading crown and this scaly gray bark. Ironwood is sensitive to cold temperatures and does not extend into the Mojave Desert or higher elevations of the Sonoran Desert in Arizona. It favors broad washes and middle slopes of large alluvial fans, often occurring with blue palo verde ( Parkinsonia florida ). The pinate gray-green leaves of ironwood features a pair of sharp, curved spines beneath each leaf along the major branches and trunk of the tree. Although many desert trees serve an important ecological role as nurse plants-aiding in the establishment of seedlings. Ironwood is also a legume with root nodules that fix nitrogen. The name ironwood come from the extremely high density of its wood, which is so dense that it will sink in water. "California Desert Plants, Philip W Rundel, Robert J Gustafson, Michael E Kauffmann."

  Prosopsis glandulosa (honey mesquite) (mezquite dulce) Fabaceae Prosopsis glandulosa var. torreyana Although most common in the Sonoran Desert areas of California, honey mesquite extends its range across lower elevations of the Mojave Desert as far north as Death Valley and over huge areas of desert and semi-desert in the southwestern United States and adjacent Mexico. It is a classic phreatophyte with roots that tap groundwater pools as deep as 30 feet or more below the soil surface. In semi-arid grasslands of the southwestern United States with summer rainfall, however, it behaves less like an obligate phreatophyte and readily invades desert grasslands. It must be remembered, however, that plant roots do not grow through dry soil actively seeking out groundwater. Roots will only follow moist fracture zones in soil profiles. Honey mesquite is quite variable in growth form. It may form a broad shrub 20-30 feet in diameter with multiple stems, particularly on dune habitats. Each pinna