Gerald A. Rosenthal and William Hart
 
 
 
 

Spring, 2005

14,036  words

101 species-with at least 20 more to come on board.

 
TABLE OF CONTENTS

I. ANNUAL FLOWERING PLANTS

A. BLUE THROUGH VIOLET AND LAVENDER.................................. 10
B. YELLOW THROUGH ORANGE.................................................... 13
C. RED THROUGH PURPLE TO MAGENTA...................................... 15
D. WHITE....................................................................................... 16

II. PERENNIAL FLOWERING PLANTS

A.  BLUE........ ................................................................................. 18
B.  YELLOW..................................................................................... 19
III. C.  RED TO PINK TO PURPLE........................................................... 21
D. WHITE TO GREEN...................................................................... 23
E.   APRICOT................................................................................... 25

IV. LARGE SHRUBS............................................................................. 26
V.
VI. TREES............................................................................................ 29

VII. CACTI............................................................................................ 30

VIII. YUCCAS......................................................................................... 35

IX. OCOTILLO AND EPHEDRA........................................................... 38
 CAPTIONS TO THE DRAWINGS

1A. GENERALIZED FLOWER STRUCTURE. The pistil constitutes the female portion of the flower while the stamen is the male part. 1B. OVARY TYPE. a) superior,  b) intermediary, and c) inferior

2A. LEAF SHAPES. a) acicular, b) linear, c) cordate, d) deltoid, e) oval, f) ovate, g) lanceolate, and  h) oblanceolate. 2B. LEAF MARGINS. a) entire, b) crenate, c) crenulate, d) serrate, and e) lobed,

3. LEAF ARRANGEMENTS. a) simple leaf with petiole. b) sessile: simple leaf lacking a petiole. c) palmately compound. d) pinnately compound. e) twice or bi-pinnately compound.

4. SPECIALIZED FLOWERS.  a) flower of a legume showing the upper banner petal, two wing petals and a final set of petals fused to form the keel petal, b) diagram of the flower of a typical member of the  aster family (Asteraceae) revealing the disk florets and ray florets that constitute this composite flower.

5. FRUIT OF DESERT PLANTS.  a) legume: a dry fruit that is much longer than wide; ; opens along two natural openings (sutures) to reveal the seeds attached to the fruit wall, b) follicle: a dry fruit that opens along a single suture,  c) berry:  fleshy fruit of the wolfberry, Lycium andersonii, d) capsule of a Yucca, e) capsule of a poppy, f) capsule of crucifixon thorn, Canotia holocasta,  f) a silique, a dry fruit resembling a legume, but with a central section (replum); found in member of the mustard family (Brassicaceae), g) silicle: another fruit of members of the mustard family; much like a silique but about as wide as it is long, h) achene: a dry fruit that does not open along natural openings, shown with an attached wing.
 LIST OF FIGURES

Figure 1.  Wooden skeleton, C. gigantea.

Figure 2. Paloverde  tree, Cercidium spp.

Figure 3. Pads of Opuntia engelmannii

Figure 4. Uprooted Ferrocactus

Figure 5. Glochids of Opuntia engelmannii

Figure 6. Grouping of jumping cholla

Figure 7.  “Mother plant” and young saguaro

Figure 8.  Solitary,  young saguaro.

Figure 9.  Multiple-armed   saguaro.

Figure 10.  Flowers of the saguaro

Figure 11.  Individual soaptree yucca

Figure 12.  Individual ocotillo

Figure 13.  Fruiting structure of Ephedra
 

The Sonoran Desert is an arid region covering some 100,000 square miles, much of it located in southwestern Arizona. This is the hottest of our North American deserts, and arguably one of the wettest in the world-receiving 5-12 inches of precipitation each year. A well-established rainfall value for a typical desert is 10 inches per year. When rainfall significantly exceeds this value, the desert biome is lost and replaced by a short grassland.  Thus, 5 inches would represent a relatively dry year and 12 a year of abundant rainfall.
   Virtually all of the rainfall is delivered either in the winter months (December thorough March) or as part of summer monsoons (July through September).  The latter rains typically form from moist, tropical air masses that can create violent, thunderstorms with potentially destructive winds.   Freezing temperatures occur at night and only a limited number of occurrences each winter.
The most distinguishing feature of the Sonoran desert is the presence of many leguminous trees that account for the bulk of the woody perennials and large, columnar cacti such as the giant saguaro and barrel cacti.  When winter rains are adequate in fallen rain and properly distributed throughout the winter months, the resulting spring flora is nothing less than spectacular. Dominated by annuals and herbaceous perennials, areas as far as the eye can scan are filled with a sea of color covering the virtual spectrum.
In a hot summer, temperatures over 110o (often more) can persist for weeks on end. The lack of hard freezes, moisture distributed through much of the year, coupled with the long growing season have created a highly adapted and diversified flora that tolerates intemperate heat, severe drought, violent rainstorms, and rebounds spectacularly with the return of ample, adequately distributed, rain.
Flora of the Sonoran Desert vary significantly in their relative abundance from place to place.  Large groupings of a particular plant or plants may be found along certain trails; yet, be far harder to find in other places of the Sonoran desert.  While plants described below were selected primarily for their abundance, they are also commonly found representatives of the major groups of flowering plants. This flora adds beauty and inspiration, especially to the pristine places that remain in our Sonoran desert.

PLANT NAMES
Common plant names are essential; one cannot reasonable call a wild heliotrope “the plant with the blue flowers and hairy leaves” without quickly running out of meaningful descriptions that differentiate one plant from another; an impossible linguistic morass would soon occur.  Common names are certainly necessary, but plants can and do carry more than one unique common name; worse, the same name can be used for more than one plant. In fact, it can be daunting: the name peppergrass is used to describe more than one hundred species of flowering plants.
Recently, I asked a fellow hiker what she called a very tiny, white-flowered plant growing close to the ground. “Why that is obvious”, she said. “It’s the belly flower-because you have to get down on your belly to see it”. It was an amusing and reasonable response that may have solved the naming problem for this plant, but what about all the other tiny flowers that required the same prostration? Belly flower number two?
 Obviously, a naming system was required that is wholly unambiguous- meaningful to everyone, everywhere. The problem has been solved because botanists use two Latin names for each plant: the first is the genus (plural: genera) or first group that a plant shares common genetic characteristics with other plants-for example, the genus: Phacelia.  There are three commonly found members of the genus Phacelia through much of the preserve. Phacelia crenulata, Phacelia distans, and least often: Phacelia campanularia.  Each plant is unique but they also share certain common characteristics with one another. Thus, they are all housed in a single genus: Phacelia.
The second name is the plant’s specific or species name.  The species name is typically descriptive such as crenulata for the fact that the leaf margins are crenulated (a certain shape).  Far more often, the first to formally describe the plant immortalizes themselves: such as engelmannii for Engelmann or greenii for Green. Some of the earliest students of plants, such as individual responsible for botanical collections and gardens in Europe during the age of great exploration, have numerous plants whose specific names recognize their contributions.
This system of naming is known as a Latin binomial or two names.  Phacelia crenulata may well be a mouthful, but it does provide a single, unique, name that everyone agrees refers to a single specific plant and none other.  Certainly makes real sense when it’s important to know the particular plant one is referring to.

PLANT IDENTIFICATION
Flower Parts. Resulting from a need to attract suitable animals to transport their pollen,  flowering plants tend to have very colorful, showy petals-often with distinctive shapes and forms. It is this part of the flower that we respond to aesthetically.   Petal (corolla) color, size, and shape can vary dramatically from plant to plant and therefore they become important features in identifying a given plant (Drawing 1A). Typically, a ring of nondescript, typically green, sepals (calyx) protects the internal flower parts. Many desert plants, belonging to the bean or legume family (Fabaceae), have developed a particularly strong relationship with insects who they depend upon to move their pollen. These flowers have petals that are highly modified to accommodate visiting insects (Drawing 2).
 The “male” part of the flower, the stamen, consists of a supporting structure (filament) upon which the anther rests. The anther contains the individual pollen grains, which are the male sex cells.  These pollen grains are truly important because they carry the male genes of the plant.  Often, there is a group of stamens and many anthers that surround a solitary pistil.
The pistil is the “female” part of the flower; it contains the female sex cells or ovules housed in the ovary-which rests at the base of the pistil. In like manner, the ovules contain the female genes (Drawing 1A).   Fertilization of the ovules by the pollen grain initiates wondrous cellular processes that culminate in fruit formation and seed development. The ovary will grow into the fruit and its ovules will become the seeds.
 Most desert flowers are said to be “perfect” because both stamens and pistils occur within the same flower. Such perfect flowers are “monoecious” from the Greek for “one house”.  All the reproductive elements are found in a single flower or “house”.  Such self-pollination is a logical arrangement since the pollen grains are positioned adjacent to the pistil; pollen can be transmitted efficiently to the stigma for fertilization (Drawing 1A).
 Desert  mistletoe (Phoradendron californicum), joboba (Simmondsia chinensis), are among the desert plants that do not produce perfect flowers.  Careful inspection of flowering mistletoes reveal the presence of either the pistil-containing, female flowers (pistillate flower) or the stamen-housing, male flowers (staminate flower)-never both. Mistletoe male and female flowers are always effectively separated in space. Such plants are termed, “dioecious”, again from the Greek for “two houses”.
 At first inspection, dioecious flower formation is an intriguing arrangement since it separates the pollen grain from the pistil. This would seem to make fertilization more difficult because the male and female reproductive elements are separated in space.   But further thought suggests that the problem with perfect flower formation is that it is too efficient-the ovules tend to be overwhelmingly fertilized by pollen of the same plant. This arrangement reduces the chance for introduction of new genetic materials, obtained from other plants.
 In contrast, the dioecious, female mistletoe favors reception of pollen from a “foreign” male plant; the chance for the introduction of novel and favorable genetic material is greatly increased. Plant survival is linked intimately to inherent plant variability, as it enhances plant ability to adapt to new circumstances and environmental challenges.
 The considerable benefit accrued by avoiding self-pollination has led to two other interesting strategies of avoidance. The anther or the pistil of a given flower reaches sexual maturity before the other member. Self-pollination is impossible because they are separated by time.  Another strategy involves the basic genetics of the plant whereby genetic makeup insures that the pollen of a given plant is not compatible with itself.
 A final important property of flowers in plant identification is the nature of the  ovary. If the other flower parts are located below the ovary, this is a superior ovary type (the flower is said to be hypogynous). Alternately, the other flower parts can be located above the ovary, this is an inferior ovary type (the flower is said to be epigynous). An intermediate arrangement is also possible (Drawing 1B).
Flowers of the Asteraceae. Sunflower-like plants are grouped into a single family, the Asteraceae (named after its most prominent member: the aster). The solitary-appearing flower typically is actually composed of many flowers. The darker, central portion of the flower consists of disk florets (small flowers); they are surrounded by ray florets. Thus, what appears to be a single flower is actually a composite of two distinct floral elements.  Some plants of the Asteraceae have both types of florets while other members have one or the other (Drawing 2).
Examine a sunflower in bloom: it’s a simple matter to envision the inner florets as a horde of flowers. This central portion, therefore, consists of a very large number of individual floral elements. Each "disk flower" has five small fused, petals and five stamens surrounding the pistil. On the other hand, the outer ray flowers seem like the petals of a solitary flower-they are not. Each “petal-like” ray is a complete flower (Drawing 2).
This wondrous example of plant complexity is not over.  Green structures beyond the central colored portion may seem like the sepals but they are modified leaves. Petals are either absent or greatly reduced structures.
Flowers of the Fabaceae. Flowers of certain legumes are modified to accommodate a working relationship with a given bee. This floral structure can have five petals: the top petal is the standard or banner petal, there are also two lower wing petals on the side, and a final pair of petals fused to form the lowest keel petal.
Nectar is stored just over the filaments of the anthers inside the keel petals. When the bee enters the flower, its body weight moves the keel petal and this, in turn, causes the anther to brush up against the bee's body depositing pollen on the obvious forager (Drawing 2).  The bee received positive reinforcement, nectar reward, for this behavior, and the flower has an effective agent for transporting its pollen. Some may see a Divine hand in such machinations.
Leaf Form and Shape.  A very important physical feature of diagnostic value in plant identification is leaf characteristics.  The margin or edge of the leaf can be smooth and continuous (entire); it can be serrated (like saw teeth) and even doubly serrated (alternating small and large teeth); rounded ridges, both large and small, are also possible (Drawing 3A).  The shape of the leaf is variable and therefore noteworthy. It can be broader at the base, middle or at the apex. It can be cordate (heart shaped) or linear (Drawing 3B).
Most leaves are simple; that is, the leaf blade is attached directly to the plant by a supporting structure known as a petiole.  Leaves attached without a petiole are sessile.  On occasion, the leaf exhibits a far more complex form, it occurs not as a single blade; but rather, multiple components that are attached to an accessory structure, which in turn connects to the plant.  This leaf form is called “pinnately compound”.  There are instances, when the leaf type is doubly or bipinnately compound, In another foliar arrangement, the leaves radiate from a central point like the fingers of a hand; this is termed: palmately compound (see Drawing 4).
              Finally, the leaves may project from the branch directly opposite each other, or they may project from one side and then the other in an alternating pattern (alternate).  Observing if the leaf is alternate or opposite, simple or pinnately compound, margins entire or otherwise, and overall shape can aid greatly in identifying a flowering plant,  and successfully distinguishing between similar-appearing plants.
Fruit.  Later in the growing season, the ovary of the fertilized flowers will mature to form the fruit that houses the new generation of seeds. There are many types of fruit and, when present, makes identification a much easier enterprise (Drawing 5)  All fruit can be divided into two groups: fleshy and dry. Fleshy fruit have a high water content-same as the many fruits of human consumption. Some desert plants produce berries, a typical fleshy fruit. The fruit of the wolfberry, Lycium andersonii is a multi-seeded berry and when opened looks like a miniature tomato (Drawing 5).
 Dry fruits contain far less water and, while the fruit itself does not afford meaningful nutrition for desert dwellers, their seeds are an important dietary source of all food groups-particularly proteins.  A dry fruit that opens along natural breaks in the wall of the fruit (sutures) is characteristic of a legume. The desert flora is particularly rich in members of the bean family (Fabaceae), all of whom produce legumes. Most everyone eats table legumes, but they have been bred for high moisture content and low fiber to enhance their edibility. Legumes characteristically are much longer than they are wide.  A follicle is a very similar fruit but it opens along only one side of the dry fruit. All desert milkweeds, an essential food plant of the monarch butterfly, produce follicles.
A dry fruit that opens along two sutures but is about as long as it is wide is a silicle. This fruit is found commonly among members of the Brassicaceae or mustard family. Another important dry fruit is the achene. Unlike the legume and follicle, that open  along natural apertures, an achene is a dry, one-seeded fruit that does not split open when mature. Think of a strawberry; it is actually a fleshy fruit whose surface is covered with achenes. (Drawing 5).
A large group of desert plants produces another dry fruit that is not elongated and bean-like. These fruit fall into a large grouping known as capsules. The seeds are released through pores (poppy) or various sutures in the wall of the fruit.  Thus, the crucifixion thorn, Canotia holocasta, produces a typical capsule. In comparison, the smokethorn, Psorothamnus spinosus, which bears a strong physical similarity, is a legume. Inspection of the fruit, which can remain persistently on the plant well beyond flowering, definitively separates these two plants even in the heart of winter.
 Other factors.  Another factor that is worth noting is the time in the growing season that the flower is first observed.  Plant physical location, such as its occurrence in open areas; for example, next to an wide  trail or roadbed (where more side light reaches the plant), its relative abundance, its odor, and its feel to the touch are all features that will become more intuitive as one acquires greater skill in plant identification.
How To Use This Guide. Most beginners will simply thumb through this work hoping to see a picture that resembles their plant of interest. This undemanding method of inquiry can work, but often there is little confidence and certainty about the plant in question and the guide fails to meet its primary objective: to enable the user to identify the plant in question. If this method of simple comparison worked effectively, there would be no need for text and botanical description.
A better approach is to begin by taking the time to really inspect the plant. Begin with the flower and the other principal parts of the plant before even opening the guide. Of course, you will note the color of the flower, but then go beyond and look to see how many petals are present, are they solitary or fused, do they form a long, tubular structure. Examine the sepals for their properties and characteristics. Are the flowers clumped at the head of the plant or distributed along the stem.
Look at the leaves and decide if they have a petiole or are sessile. Are they simple or compound. What about the margin and the shape of the leaf. Is the leaf form uniform along the stem or are the basal leaves different aerial counterparts. Are the leaves distributed along the entire stem or concentrated at the base of the plant. Are the alternate or opposite.
Examine the plant for fruit, this is a truly valuable diagnostic tool. Touch the plant, is it smooth or pubescent or armed with thorns. All of the botanical description that I have written is geared to answer the above questions. Finally, if you have any real interest in learning this flora, invest in a hand lens that is comfortable to use without undue eye strain. This simple device will open a new dimension of detail and structure to your analysis. Be patient, this is not a skill that is acquired the first time you decide to identify a particular plant. With practice and gained knowledge, it becomes much easier, and your confidence that you have made a correct identification properly justified.
 Due to the significant variation in the size of plant parts as well as the plant itself, little dimensional data have been provided. Instead, emphasis was placed on the properties and features that “jump out” for the careful observer.  The overriding objective of this work is to enable a motivated person to become familiar with the desert flora and to enhance enjoyment and understanding of one of the Earth’s unique and truly special ecosystems.
A Final Word.  For serious students of the desert flora, consider purchasing a 10x hand lens. This simple magnifying instrument opens a world of internal details and colors that are truly fascinating and absorbing. It is a particularly worthwhile purchase for families with children. Kids seem mesmerized by the beauty and wonder of the Lilliputian world found within a typical flower. These instruments can be purchased on-line and can be obtained for as little as $5 to $30-35 at the high end.  I prefer a two-element hand lens (10x and 5 x) that can be overlapped to produce 15x magnification; it can be obtained for $5.
 
The Sonoran desert annual flora, particularly after a winter with adequate rain, appropriately distributed, is incredibly rich in its abundance and diversity. This vast assemblage of annual plants have one season to grow vegetatively, set flowers, and develop fruit and seeds. Changes happen quickly. Once the summer sun generates long, hot, sultry days, conditions for these ephemeral plants worsen; they abruptly depart the desert scene.
 Many annuals maintain growth-inhibiting substances in their seed coat that prevents germination until sufficient rain has fallen to leach these substances. This strategy insures adequate moisture for the developing seed. The seed coat can also be hard and impervious requiring tumbling and grinding to slowly etch the hard coat. Rainwater, carrying and moving seeds, particularly in sandy area and along arroyos and bajadas, can achieve this goal.
Desert annual seeds can remain dormant for many years awaiting the arrival of sufficient rainfall for germination. When this occurs, the desert can become a carpet of colors as far as the eye can see. These circumstances fortunately occur in the Sonoran desert from time to time.  Rarer annuals make their appearance and the numbers of a given plant in a particular area can reach into the tens of thousands.
 Annual plants tend to have soft body tissues and lack woody materials. In general, they are far less massive than perennials. This is not to say that an annual flowering plant cannot reach significant stature; some are taller than most hikers. But they do not accumulate a large mass of woody tissues.
 

A. BLUE THROUGH VIOLET AND LAVENDER
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SCORPIONWEED  (Phacelia crenulata)
 Family: Hydrophyliaceae (water leaf)
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 An early flowering plant with five, sky-blue to violet petals.  The veins running through the petal are blue-purple, as are the long and slender filaments, which support the anthers.
 Leaf margins are distinctively lobed consisting of 5-7 segments per leaf; alternate leaves emerge directly from a flower stalk that is coarsely pubescent.
The flower head is usually coiled; as it unfolds “new” flowers are exposed for pollination. It is this curved appearance that reminds some of a scorpion tail. Other spring annuals share this characteristic.
 
 
 
 

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WILD HELIOTROPE  (Phacelia distans)
 Family: Hydrophyliaceae (water leaf)
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 This Phacelia and P. distans are common member of our desert flora, with hundreds of individuals seen on a single hike. They appear early in the spring. Phacelia flowers support five blue to purple petals with distinctive purple venation.  Deep purple filaments support white anthers that darken with age. Stamens project well above the corolla while the pistil resides in a cavity at the flower center.
These two Phacelia are difficult to tell apart from their flowers. However, the leaves of P. distans are alternate and pinnately compound. This feature most effectively differentiates these two plants.
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DESERT BLUEBELLS,  (Phacelia campanularia)
 Family: Hydrophyliaceae (water leaf)
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A fair less commonly found Phacelia is the desert bluebells (Phacelia campanularia); in many ways, the most visually striking of the three Phacelia. Flowers are formed from five, fused petal segments that creates a deep, bell-like shape.  Five to six, yellow-tipped anthers that extend above the corolla and a far smaller green calyx; as well as attractive, deep petal coloration make this a relatively easy plant to recognize.
Cordate leaves with red edges. All Phacelia deposit a nectar reward at the base of the petal, which is covered by a portion of the stamens. This obstacle forces a foraging bee to dislodge pollen while securing its nectar reward.
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BLUE DICKS  (Dichelostemma pulchellum)
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 The most striking feature of this plant is it’s atypically long, solitary flower stalk with six bluish-violets petals. The stamens are yellow and conspicuous.  This plant often occurs as a solitary, single member.
Close inspection of the petals reveals a distinct zone of color running through the center of each petal. Typically, there is a group of outer petals and another that surrounds the pistils and stamens.  The stamens are bright yellow and are housed in a letter Y-shaped structure that also houses the ovary; at its base are three, purple-segmented zones. Multiple flowers emerge from a single set of sepals.
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FILAREE (Erodium cicutarium) ______________________________________________________________________________
 Filaree is often the first plants to make a vernal entrance.  When tiny, there is a mix of vivid red and green foliage that supersedes flower appearance. Over time, with full chlorophyll development, the red foliage is lost. This five-separate-petaled plant has reddish-blue to magenta color with purple at the base.
The ovate leaves have lobed edges.  Acicular fruits develop quickly from the flower.
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CHIA   (Salvia columbariae)
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 This visually striking, violet spring plant is a member of the mint family. Thus, look for a four-sided, square-shaped stem. Small, lavender flowers emanate from a large flower head that is persistent when the flowers are no longer present. As the plant ages, the globose flower head dries and hardens to create an appealing plant for dry flower arrangements.
 The green sepals are sharply pointed and project beyond the petals. The flower head contains modified green leaves (bracts) with pronounced red areas at the edges; individual flowers consist of two types of petals: an upper petal consisting of four, fused petals and a lower, larger petal with purple spots and streaks.
 Leaves are mostly basal, oblong and pinnately compound with a crinkled texture to the leaf surface and recessed veins. The crushed plant emanates a pungent odor. This is an excellent example of the value of a simple hand lens for revealing a wealth of fascinating structural flower details.
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COULTER LUPINE  (Lupinus sparsiflorus)
 Family: Fabaceae (legume)
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 The inflorescence (flower head) has many individual flowers radiating off the flower stalk in an alternating pattern. There are two conspicuous petals, the banner petal has a yellow patch with reddish spots and keel petals curved upward and pubescent.
Immature flowers are typically found at the apex of the inflorescence until later in the spring. When the young flower is fertilized, the grayish-yellow region turns a wine-red. Still later, the petals lose more color but persist on the inflorescence.
The leaves are lanceolate and whorled. This is not Arizona lupine (Lupinus arizonicus) which has a magenta flower. This is an aggressive competitor that can occupy large areas, often in conjunction with Mexican golden poppies, creating a spectacular carpet of colors.
This legume is heliocentric which means that it changes its orientation in harmony with the diurnal movement of the Sun across the sky. Scientists believe that this activity provides additional internal flower warmth to increase attraction of insect pollinators.
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BAJADA LUPINE (Lupinus concinnus)
 Family: Fabaceae (legume)
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 This lupine is a small, prostrate legume with densely pubescent, palmate leaves (6-8). The young petals are purple, but the older, more developed flowers are magenta. All of the flowers are supported on a single flower stalk.  Banner petals are an off white while the keel petals bear their color primarily at the petal edge. This plant favors sandy soils, and can be abundant along roadsides and other open areas.
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GILIA  (Gilia flavocencta)
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 This pale blue to lavender member of the Phlox family possesses a thin, overall delicate appearance. Flowers composed of five distinct petals that fuse at their base. While the filaments lack color, the anthers are blue-green. A three-lobed pistil and the stamens project above the corolla; bright yellow cavity houses the stamens and pistils. Small, green calyx; pointed with purple streaks.
 Linear leaves with fine, narrow projections are attached primarily at the base of the flower stalk.
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FIESTA FLOWER (Pholistoma auritum)
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A spindly plant with four-sided stems that interlock creating a tangled mass of plant parts. Flower stalk and flowers project from a common leaf axil.
Linear, rosette leaves
 

B.  YELLOW  THROUGH ORANGE

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FIDDLENECK   (Amsinckia menziesii)
 Family: Boraginaceae (borage)
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Arguably, the most abundant spring flowering plant; if seasonal rains are plentiful, it is not unusual to see many thousands during a single outing.  Favoring large groupings, it is rarely seen as a solitary plant.
The petals are tubular with five orange to yellow segments; individual petal can be marked with five red to orange splashes of color. The stamens and pistils are buried deep within the flower. During the early part of the growing season, the plant is less than 6 inches tall, but at the end of the season it can reach nearly three feet.
 Early in the flowering season, the flower head is curved, bearing a resemblance to the head of a fiddle. Over time, the flower head expands to expose younger flowers to pollination.
The leaves are narrow and linear, bristling with leafy hairs. (This explains why one of many alternate  common names for this plant is: devil’s lettuce).  The hairs along the flower stalk are even more pronounced. At the leaf axil, where the leaves emerge from the stalk, a single large leaf and several smaller leaves are found.
 

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MEXICAN GOLDEN POPPY (Eschscholzia californica)
 Family: Papaveraceae (poppy)
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 Capable of covering any entire mountainside, this is one of the most aesthetically pleasing, spring flowers. Bearing four petals, it can vary in color from smooth yellow petals with just a touch of centrally located orange, through all mixtures of yellow and orange, to a largely orange blossom.  Most flowers, however, are yellow with an orange inner region containing the stamens and pistils.
 Flowers arise at the apex of the stalk and all of the petals are joined in a small, green, cup-like structure formed by the sepals. Bluish-green leaves, typically with three segments, each is deeply grooved and divided. Fruit: a capsule housing a horde of seeds.
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BLADDERPOD MUSTARD  (Lesquerella gordonii)
 Family: Brassicaceae (mustard)
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Flowers with four, yellow petals. The six stamens are conspicuous: 4 are large and the final pair is smaller.  These two features are common to plants of the mustard family (Brassicaceae). Look for the spherical fruit that form early in plant development. Leaves are lanceolate.
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CALIFORNIA GOLDFIELDS  (Lasthenia gracilis)
______________________________________________________________________________    Flower structure is that of a typical member of the Asteraceae, but it is small (no more than one-half inch). All flowers are positioned at the top of the stalk. A very slender, delicate plant with small, opposite, linear leaves. Two or more leaves are clustered at the axil This is a communal plant and it can cover extensive areas with hundreds of flowers.
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CALIFORNIA SUNCUPS  (Camissonia californica)
 Family: Onagraceae (evenign primrose)
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 Four separate, lemony yellow corolla that is projected backwards.  Numerous red spots pepper the area around the base of the pistils and stamens; these reproductive structures project well out into the plant, almost reaching the edge of the petals.
 The flower stalk is thick and substantial thereby creating a rigid, erect appearance to the plant.  Leaves form as a basal rosette, lanceolate, and deeply lobed; becoming more linear as leaves progresses up the stem.

SLIM EVENING PRIMROSE (Camissonia brevipes)
 Family: Onagraceae (evenign primrose)
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 Similar to C. brevipes with four, lemony-yellow, ovate sepals. Eight yellow stamens, globose stigma; pistils as long as the stamens.
Leaves (sparse) linear to lanceolate with a notable midrib (red) and red areas at the leaf apex.  Stem supports leaves throughout its length with few, widely spaced flowers at the apex.

SILVER PUFFS   (Microseris linearifolia)
 Family: Asteraceae (sunflower)
The corolla consists of uniform, light yellow ray florets surrounding a group of smaller florets. Its calyx covers the base of the flower and extends above two-third the way to the petal ring.  On occasion, the sharply pointed sepals extend well beyond the petals.  Flowers are borne on an elongated flower stalk that is free of foliage except for a group of basal, rosette-like leaves.
Flowers mature to a distinctive silvery, lacey seedhead composed of a black achene that is dispensed readily by wind currents by a five pointed silver wing.
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LONDON ROCKET  (Sisymbrium irio)
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Plant has a distinctive open, slender appearance. Multiple yellow flowers clustered at the apex with six yellow anthers and a dark red style and green stigma.
Upper leaves are linear, highly elongated (3-4 “), and alternate. Lower leaves are broader and often occur as two slender side wings accompanying a much broader central leaf.
______________________________________________________________________________ BLACK MUSTARD (Brassica nigra)
 Family: Brassicaceae (mustard)
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 Large mustard, densely pubescent. Flowers: four, yellow petals growing from the apex of the stem.  Commercially cultivated varieties provide the seeds for mustard condiment.
 

C. RED THROUGH PURPLE TO MAGENTA

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RED MAIDS (Calandrinia ciliata)
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Five separated reddish purple petals and two overlapping sepals.  This is a small, prostrate plant with alternate, lanceolate leaves that bear red areas at the leaf apex.
Native Americans dried the shiny black seeds to prepare an edible, oily meal.
 
 
 

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OWL CLOVER (Castilleja exserta)
Family: Scrophulariaceae (figwort)
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 Look for a magenta flower head with many petals that are thin and elongated with fine pubescence at the margin and a brown-red color at the base.  Dispersed with this color mass are the ovary-bearing portions that can be identified by the splash of bright yellow over a scarlet-red base on the petal face. Can be a parasite on roots of other flowering plants.
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NEW MEXICO THISTLE (Cirsium neomexicanum)
 Family: Asteraceae
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A large conspicuous plant that can reach more than 6 ft in height.  Flower has only magenta to pink ray florets. Florets surround the upper quarter of the flower head. Green bracts surrounding the flower are sharply pointed. Upper bracts are erect, but lower ones are angled downward.
Leaves attached to stem at the axils are armored. Spiny, dark green leaves, deeply grooved, shiny and can exceed nine inches in length. A favorite of a large array of insect pollinators.
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EATON’S PENSTEMON (Penstemon eatonii)
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 Striking red flowers that cluster along an elongated flower stalk with five lobed corolla.  Flower attached to stalk with a red pedicle. Five stamens, one nonfunctional. Filaments with a touch of red, anther divided into two segments. Five pointed calyx.
Opposite leaves are ovate at the base but become lanceolate at the tip. Hummingbirds are attracted to red flowers and their beaks are adapted to reaching the nectar reward at the base of the long, tubular corolla.
______________________________________________________________________________PARRY’S PENSTEMON (Penstemon parryi)
 Family: Scrophulariaceae (figwort)
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Magenta to pink corolla funnel-shaped with five distinct lobed. Flowers borne on a long flower stalk. Sterile stamen with lacey golden-yellow pubescence, fertile stamens divided into two segments, milky. Filaments clear at base but red at the upper portions.
         Large opening at the center of the flower allowing easy view of the internal organs. A favorite of hummingbirds and other insects.
______________________________________________________________________________DESERT STORKBILL  (Erodium texanum)  ______________________________________________________________________________
Five, separate magenta petals that can be as large as an inch. Solitary, cordate leaves emerge from the base of the plant and at the axils of the flower stem. Leaf margins are lobed and lightly grooved. The long, linear fruit is very reminiscent of filaree.
 

D. WHITE
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POPCORN FLOWER (Cryptantha angustifolia)
 Family: Boraginaceae (borage)
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Another common plant of the spring assemblage, the flower is very tiny with five fused white petals; there is a yellow-colored central cavity in the flower. Stamens and pistils are hidden cryptically inside this cavity.  Its green sepals are conspicuous in comparison to the petals. Most flowers have a curved, coiled appearance, which opens as new flowers are exposed for pollination.
Bristly hairs cover the entire plant. Its alternate leaves are thin and lanceolate. Often, there is a single leaf at the region where the flower projects from the flower stalk.  A similar appearing plant, the Arizona popcorn flower (Plagiobothrys arizonicus) has much larger leaves.
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DESERT CHICORY  (Rafinesquia neomexicana)
 Family: Asteraceae (sunflower)
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 The flower stalk, which can be substantial in width, houses tiny, alternate leaves that are long and thin and deeply grooved with numerous thin sections that project from the elongated, central portion of the blade.  Leaves are sessile but a portion of the lower blade can extend beyond the stem on the opposite side.
 The lustrous, white ray flowers bear multiple, purple streaking on the underside of the petals. The purple sepals extend halfway up the petals. The tip of the stamen breaks into two, curved segments; they surround an ovary made of many segments.
 This plant is very similar in its appearance to white tackstem (Calycoseris wrightii); however, the chicory flower stalk lacks tiny, tack-shaped glands that cover the flower stalk of C. wrightii.
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PEPPER GRASS  (Lespidium virginicum)
 Family: Brassicaceae (mustard)
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 The flower stalk is very thin and delicate. Leaves are alternate, linear, and grooved.  Just beneath the white flowers are bands of alternating, persistent fruits paddle-shaped that are silicles. Fruit wall has a distinct midri, and a small section of missing tissue at the apex. All flowers and fruit are borne at the stem apex.
 
 

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WISHBONE 4 O’CLOCK  (Mirabilis bigelovii)
 Family: Nyctaginaceae
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 Flowers at stalk apex where leaves also tend to bunch. When young, the flowers, wrapped and enclosed by the calyx, show a splash of magenta but later a white flower emerges. Petals are lacey, lobed, finely veined; stamens made of white filaments supporting golden-yellow anthers.
Cordate leaf with small petiole. Interesting common name derived from the late afternoon opening of the flower. A wishbone pattern is seem in the branching stems.
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ARCH-NUTTED COMB BUR ( Pectocarya recurvata)
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 Among the earliest annuals to usher in the flowering season creating a virtual carpet of tiny, white specks-as drops of paint from a brush. Flower with five petals but so tiny as to need magnification to be seen fully. Fruit is a four-chambered capsule with barbed margins.
 

Perennial plants are persistent, surviving the long, hot summer months by a variety of strategies such as loss of water-consuming plant parts-particularly leaves. Many desert plants, such as the ocotillo, exhibit episodic loss of foliage. When the rain returns, a new burst of leaves appears; this cycle can be repeated  several times during the growing season.
 Being perennial, there is more time for development and these plants can grow and flower at prescribed times of the year. Thus, there are distinct waves of spring, early summer, and late summer perennial flowerings. Many perennials are herbaceous. They do not produce long-lasting, woody tissues; their softer tissues generally die back at the end of the growing cycle, but send up new growth the following year. Some flowering plants are biennial-they are geared to a 2-year life cycle.
 Other desert perennials, such as the desert trees and shrubs, are woody and far more persistent than herbaceous perennials. They attain much greater size and experience a significant yearly increase in biomass. There is no formal delineation that distinguishes a small tree from a large shrub. In general, trees tend to be far more massive as they accumulate more woody tissues than do shrubs-even large ones.
Finally, many desert perennials have conspicuous hairs (pubescence) on the leaves. Their presence adds to the ability of the plant to reflect solar radiation (typically they are lighted colored) and they may also break up the air mass moving over the leaf surface and thereby impede evaporation. Hairs can also be a deterrent to animal feeding and afford a means of limiting herbivory.
 

A. BLUE TO VIOLET

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NAKED DELPHINIUM  (Delphinium scaposum)
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A visually striking plant. Royal blue to purple flowers with four petals and five sepals; one sepal forms a spur that projects to the back of the flower. This spur is a nectar repository; foraging bees are covered with pollen while securing their nectar reward.
Inflorescence is a raceme, in which flowers emerge in an alternating pattern along the stalk. Fruit:  a capsule that is divided into three segments.
 The basal leaves are palmately divided with round-tipped lobes.
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SMOKETREE  (Psorothamnus spinosus)
 Family: Fabaceae (legume)
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B. YELLOW

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BRITTLE BUSH   (Encelia farinosa)
 Family: Asteraceae (sunflower)
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 The flower has  bright yellow ray florets that project well beyond the orange-yellow disk florets . A distinct green region can occur in the center of the flower.  The flower stalks protrude well above the leafy portion of the plant. During time of abundant rainfall, the leaves assume a silvery sheen but this dulls with the onset of drier weather.
 There is evident that this plant produces a chemical (allelochemical) that is released into the ground to inhibit growth of other plants. This may help in explaining why it's among the most abundant of the desert perennials and such an aggressively successful competitor. A plant greatly favored in home and commercial landscaping.
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GOLDENEYE (VIGUIERA)   ( Viguiera deltoidea)
 Family: Asteraceae (sunflower)
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  A fairly abundant desert perennial. Leaves with a triangular shape (thus the specific name: deltoidea after the Greek letter: delta) that tends toward cordate, and a texture that is wrinkled and rough to the touch. The leaves project as a pair (alternate), from the flower stalk.  Plants produce a typical flower for the Asteraceae: disk and ray flowers. The former are light yellow and the latter are a darker yellow. Foliage is dark green.
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CAMPHORWEED  (Heterotheca psammophila)
 Family: Asteraceae (sunflower)
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Camphorweed is a woody perennial with a finely grooved, gray stem. Leaves are (thickest in the center) with fine serrations on the margins that may be absent and a deeply groove midvein.
 Flowers consist of two brightly yellow ray florets and orange disk florets that project from the center of the flower head. A distinct camphor odor is released, when the foliage is crushed.  In time, a single-seeded achene appears.
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TRIXIS  (Trixis californica)
 Family: Asteraceae (sunflower)
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Ray florets are absent; disk florets are bright yellow and protected by green bracts. Flower has three lobes in the lower portion and a two lobed upper part that can be curved backward.  Dark green leaves are lanceolate.

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DESERT MARIGOLD  (Baileya multiradiata)
 Family: Asteraceae (sunflower)
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 This is a common herbaceous biennial with mostly basally located, alternate, deeply lobed, and finely pubescent gray-green leaves with a silvery sheen. The bright lemon-yellow composite flower is borne on long stalks well above the basal leaves. Both the tri-serrated lemon-yellow ray and orange-yellow disk florets are abundant, numbering in the dozens.
 A favorite site is along disturbed areas such as roadsides; thrives in sandy soils; a fierce competitor that benefits from its tolerance to drought conditions.
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GREEN’S BIRD TREE TREFOIL (Lotus greenii)
Family: Fabaceae (legume)
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 This plant is one of the earliest perennial plants to flower.  Look for a rosette of five to six leaves positioned at the bend of a flower stalk. Being a legume, the flower produces banner and wing petals that look similar and are a bright yellow. The keel petal is noteworthy because the underside is a striking red. These petals give the plant a striking overall yellow and red color that combined with leaf form makes its identification much easier.
About a month after the flower opens, the ovary wall has grown sufficiently to create a thin, elongated pointed seed pod (legume) that grows larger with time.
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TURPENTINE BUSH (Ericameria laricifolia)
 Family: Asteraceae
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 A common, small perennial densely packed with gray-green, linear leaves. Glands in the leaf store compounds that impart a pungent, turpentine-like odor.  Ericameria  flowers contain many ray and disk florets. By spring, its seeds (achenes) have dispersed, but it continues to produce  light-green, lacy foliage free of flowers.
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SNAKEWEED (Gutierrezia serotina) ______________________________________________________________________________________
The small, bright-yellow flower consists of ray and disk florets. The green leaves are small and linear. The plants are densely branched with bright green stems, but the leaves are rather sparse; this creates a sense of openness about the plant.
 
 
 
 

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DESERT SIENNA (Cassia covesii)
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 This perennial legume hangs close to ground level. Pinnately compounds leaves, and a five petal, bright yellow flower with conspicuous anthers. The rachis hold three pairs of elliptical leaflets bearing fine, white pubescence.
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INDIAN MALLOW (Abutilon palmerii)
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 Five petals matched by sepals that are almost as large.  Flower stalk and leaf emerge from a common point on the stem.  Leaves cordate with gentle serrations. Leaves alternate, sessile and pubescent. Fruit: multi-chambered capsule.
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MENODORA (Menodora scabra)
 Family: Oleaceae (olive)
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Four, widely spaced yellow petals, occasional red on the underside. Red spots can be present at the base of the petal. Reproductive structures prominent and projecting well above the base of the corolla. Globose stigma; green pistil.
Linear leaves with a prominent midrib, gently toothed. A small, green curved tendril-like structure projects from the leaf axil.
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MARICOPA MILKVETCH (Astragalus lentiginosus)
 Family: Fabaceae (legume)
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 C. RED TO PINK TO PURPLE

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BUCKWHEAT  (Eriogonum fasciculatum)
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Buckwheat flowers are an interesting mixture of red and white blossoms that protrude from the terminal portion of the flower stalk. The red is seen when the flower is closed, but upon opening, it reveals six white petals with a central green zone. Very fine white filaments support red anthers.
The basal leaves are diminutive, margins entire, lanceolate, and possess fine pubescence.
 

______________________________________________________________________________ FAIRY DUSTER (Calliandra eriophylla)
 Family: Fabaceae (Bean)
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 One of the most visually appealing plants of the desert due to its puffy, delicate flowers, well deserving of its common name. Several pink flowers, with dozens of long, delicate white stamens that are pink at the base, make up a single "flower puff".
 This is a legume finely pubescent pod opens along the sutures with sufficient force to eject the seeds far from the plant. The open, spent pod can remains on the plant. Leaves are deep green, twice pinnately compound, pinnae (5-12) tiny.
A desirable plant who people who wish to encourage hummingbird visitations.  Another closely related species: C. californica has a vivid, red flower.
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PARRY PENSTEMON  (Penstemon parryi)
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 Leaves emerge as alternate pairs, long and linear along the flower stalk. Bright pink flowers project from specific points along the stalk.  A long, tubular corolla terminates in five segments that surround the stamens and pistils. The green calyx is attached to the flower stalk by a thin, red structure. Opposite, bluish-green leaves are narrow and smooth.
Its color and elongated, tubular petals are adaptations to its dependence on hummingbirds for pollination.
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PEREZIA (Acourtia wrightii)
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Flowers are violet to pink with numerous flowers grouped into a single head clustered at the apex of the stems. Petals appear as a group of three: one is shaped like a ray floret with three lobes and the remaining petals are lobed. Leaves are oblong, serrated and wrinkled. Base of leaf locks onto the stem.
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SMALLSEED SANDMAT (Chamaesyce polycarpa)
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Prostrate plant with minute four-petaled flowers. Often scalloped appendages, each with a red to black gland at their base.
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VERBENA (Glandularia gooddingii) (Verbena gooddingii)
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 Short-lived perennial with flowers clustered at the top of the plant. Five, pink to lavender petals are attached only at their base; Leaves are opposite, divided into three segments with serrated margins.
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SPREADING FLEABANE (Erigeron divergens)
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 Aster with red to purple ray florets and yellow disk florets; a green band surrounds the disk florets. Green bracts uniform in size, creating a small cup upon which the flower rests.
Leaves are alternate, narrow and elongated.
 

D.  WHITE TO GREEN

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BURSAGE  (Ambrosia deltoidea)
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 This perennial, evergreen shrub, generally one to three feet in stature, has alternate, triangular leaves with whitish pubescence on the underside. The margins are serrated but nearly lobed. Under moisture stress, the leaves are truly minute, but they attain a far more massive size when rainfall is abundant.  This difference in leaf size can be ten-fold or more.
The flower head is green, in small grouping borne on a spike found at the terminal of the branch. The female flowers are closer to the base of the flower spike and a round bur, 1/2 inch in diameter, with slender spines.
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CANYON RAGWEED  (Ambrosia  ambrosioides)
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 Large, triangular-shaped, coarsely serrated leaf. Flowers green and consisting of disk florets only. Basal flowers are pistillate and produce all of the fruit while the upper portions of the stem yield only male, staminate flowers. Fruit is a single-seeded achene with a large, conspicuous burr.
This is a prolific pollen producer that causes much suffering during the allergy season.
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DESERT ANEMONE (Anemone tuberosa)
 Family: Ranunculacaeae (crowfoot)
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An unusual flower that lacks petals but has a calyx that looks like white petals. Many stamens, Flowers bunched at apex of stalk. Flowers develop into a  delicate, cylindrical seed head that disintegrates to release the seeds.
Leaves divided into three segments, grooved, highly divided, basal or whorled mid-way up the stem.
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DESERT TOBACCO  (Nicotinia obtusifolia)
 Family: Solanaceae (nightshade)
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 Flowers are cream to greenish-white and tubular with petals that are flared. Desert tobacco produces a new crop of flowers in response to additional rainfall.  Leaves lanceolate, pubescent and sticky to the touch.  Storing significant levels of nicotine, this plant was sought as a tobacco by a host of early desert dwellers.
 A related plant is the tree tobacco, Nicotiana glauca, with yellow flowers that also produces a strong stimulant, but it is not nicotine. N. glauca stores a similar alkaloid: anabasine; that accounts for virtually all of the alkaloid content.
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DESERT RHUBARB  (Rumex  hymenosepalus)
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 Massive plant with large thick, lanceolate to oblong, dark green leaves beneath a bronze-brown flower stalk. Flowers with six petals, small, and green. Large number of flowers combine to form the massive flower stalk.
 Sandy washes and fully illuminated areas, such as an open roadbed, are favored habitats for this perennial plant. Its underground storage structure (tuber) is a source of tannin for tanning; the above ground portions have a variety of medicinal uses.
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WHITE PRICKLY POPPY (Argemone polyanthemos)
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 This massive poppy can reach five feet with leaves that can extend eight inches. Leaves strongly pinnately divided, prickles on leaves and stem are formidable. The flowers, extending to five inches, are white with a central area filled with yellow stamens; three petals thin and delicate, readily moving in the wind.
 Distasteful to grazing animals; thus, it tends to favor stressed, over-grazed areas.
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BLACKFOOT DAISY (Melampodium leucanthum)
 Family; Asteraceae (sunflower)
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Typical daisy-like appearance with 8-10, white ray florets with a two lobed edge. Far more numerous, yellow disk florets concentrated in a small space. Many flowers emanate from a common place at base of plant. Five, ovate, green bracts.
Leaves dark green, narrow to oblong and opposite.
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WILD CUCUMBER (Marah gilensis)
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 This is a perennial vine with delicate tendrils. Petals white and star-shaped that gives rise to a small, green globose fruit with pointed projections, much like the top of a mace. Leaves light green in three segments. Top segment is sharply pointed with the bottom segments are notched. A rapidly growing perennial that can cover completely the plant that it uses for support.
 Marah gilensis supports a large underground tuber, a starch-laden, underground storage organ that is a modified stem.
 
 

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SPREADING FLEABANE (Erigeron divergens)
 Family: Asteraceae (sunflower)
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 Green, multiple-branched stem with fine pubescence. Flower: densely packed disk florets and on the order of 100 delicate ray florets that are white with splashes of lavender. Calyx is uniformly sized creating a solid cup supporting the other flower structures.
Leaves largely linear but broader at the apex, entire, alternate, sessile; covered with fine pubescence.
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DESERT PINCUSHION  (Chaenactis stevioides)
 Family: Asteraceae (sunflower)
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 White, pincushion-like flower head composed only of ray florets at the tip of the flower stalk. Green bracts uniformly sized and covering about three-quarters of the base of the floret.
 Leaves are pinnately lobed, alternate, pubescent, with tips that are frequently curved.
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ODORA  (Porophylllum gracile)
 Family: Asteraceae (sunflower)
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D.  APRICOT

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GLOBEMALLOW   ( Sphaeralcia ambigua
 Family: Malvaceae (mallow)
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Flowers are usually apricot-orange, but can be red or pink. Five petals overlap to form a shallow floral cup. Numerous yellow stamens surrounds pistil which rises from green tissues at its base.
Leaves are markedly wrinkled and deep green and contrast sharply with the chocolate-brown stem. Viewed with a 10-x hand lens, the leaf surface is blanketed with hairy projects that look like stars filling the nighttime void.  Each leaf is divided into three segments with ruffled edges and conspicuous veins on the underside. Globemallows can dominate an area and number in the tens of thousands when winter rains are abundant.
 
 

The division between perennial flower plants and large scrubs admittedly is arbitrary. Perennial plants that attained larger size or possessed more woody tissues were placed in group III.  _____________________________________________________________________________ CHUPAROSA  (Justica  californica
Family: Acanthaceae (acanthus)
_____________________________________________________________________________________------- Seemingly in perpetual bloom, this drought resistant perennial is an important food source for hummingbirds attracted to its red tubular flowers, formed as terminal clusters, that have several annual cycles of bloom.  On occasion, a yellow tubular flower is formed.  Flowers have a two lobed upper portion and a three lobed lower section.The stems are grayish-green and they grow so as to form a tangled mass of structures. Leaves elongate and drooping in appearance. A favored food resource of hummingbirds.
Most distinct features are the light green, alternate, leaves covered with a delicate, silvery pubescence; margins entire to gently serrated.  Most leaves solitary, but they also bunch at the stem apex. A pleasant,  pungent, sage-like odor is provided by crushed leaves. Calyx is minute, deeply grooved, corolla made of five, fused, lavender petals. Flowers borne at the axils. Stigma deep purple, style much lighter, ovary extends well beyond the stamens.  Fine, white pubescence inside the flower at the base of the petals.
CRUCIFIXON THORN (Canotia holocantha)
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 A shrub-like tree with a small but stocky trunk with thin, narrow branching. Bark is light brown and deeply furrowed.  Twigs responsible for photosynthetic activity; black, cushion-like structure at the base of twigs and flowers.
 Flower with five-lobed sepals and five, white petals. Fruit is a dry, woody and highly persistent five-segmented capsule. On occasion, much of the plant is covered with dark, dried and persistent capsules. This is the only plant in the genus: Canotia.
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WOLFBERRY  (Lycium andersonii.)
 Family: Solanaceae (Nightshade)
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 An abundant scrub, the leaf shoots emerge perpendicular from the branch. Oval, sessile, small leaves are arranged so that several arise at the leaf axil and other singularly and alternately from the branch.
Flowers are tubular, five lobed, greenish white to greenish yellow. Stamens project above the other flower parts. Fruit is a small, red, fleshy berry with many seeds.
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DESERT HACKBERRY (Celtis pallida)
 Family: Ulmaceae (Elm)
_____________________________________________________________________________ Twig angles in a repetitive manner between the axils that house two sharp thorns, frequently with a small barb, that protects the plant. Simple, lanceolate leaves, generally entire when juvenile but gently serrated in older foliage. White flowers produce an oval, edible berry that matures into a yellow-orange fruit that is prized by many birds.
This is a member of the Elm family that favors sandy washes and other open areas.
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GREYTHORN  (Ziziphus laricifolia)
 Family: Rhamnaceae (Buckthorn)
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Flowers, whitish-green and cluster on the stem, give rise to a blue-black fruit. Often confused with wolfberry, the stem is spiny and gray. Leaves are dark green, oblong, and pubescent. Look for the light gray stem and branches. Flowers are small, whitish green, clusted at the end of the stalk.
The fruits are eaten by birds, especially white-winged doves and Gambel's quail.
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DESERT BROOM (Baccharis sarothroides)
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 Four-sided, square stem; foliage a light, yellow-green. Leaves small and linear are present in great abundance. This is a dioecious species; female: white flowers only with disk florets that produce an abundance of white, silky, wind-dispersed seeds that cover the plant in a large, cottony masses that drifts in the wind like snow.
 This is an aggressive competitor, frequent found growing from within another plant; abundant in distressed and disturbed sites.
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CREOSOTE BUSH  (Larrea tridentata)
 Family: Zygophyllaceae (caltrop)
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 This scrub has an open, lacey appearance with the foliage clustered tightly around the stem-particularly at their axils.  Dark green leaves are small, ovate to oblong, opposite and composed of two leaflets. The excretion of resinous materials makes the leaves sticky to the touch.  The flowers are tiny, having five bright yellow petals and  ten prominent golden-yellow stamens.
 Later, the fruit, looking like a small, wooly ball, about the size of a small pea, appears. This plant has a distinctive odor when the leaves are crushed; these phytochemicals are released to create a pungent  fragrance.
Creosote bush favors disturbed sites resulting from fire or compaction by grazing animals.  In such stressed environments, it is an aggressive competitor that dominates the local vegetation to become the dominant plant to create the appearance of a  "creosote forest”.
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JOJOBA  (Simmondsis chinensis)
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  This plant is a woody, evergreen shrub whose leaves are opposite, oval or lanceolate, gray-green. Water loss is minimized by the presence of a waxy cuticle covering the leaf surface.
Jojoba is almost always dioecious. Female flowers are small, pale-green and usually clustered at the nodes.  Male flowers are yellow, larger, and also occur in clusters. Reproduction is through a green capsule that houses up to three seeds.
 
Jojoba is desired for its fine, light yellow, odorless, wax-like material extracted from the seed and used in many industrial products as a high-temperature, high-pressure lubricant, and as a low-calorie, non-cholesterol edible oil. It serves many functions previously served by whale oil. Nearly 40,000 acres are currently under cultivation in the Southwest.
 

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FOOTHILLS PALOVERDE (Cercidium microphyllum)
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 Arguably, the most ubiquitous Sonoran desert tree, this legume is green due to the presence of chlorophyll-laden woody tissues. Branches end in a sharp point.
Flowers with five petals: four are yellow but an upper petal is white. C. microphyllum  is aptly named because the leaflets are so tiny. The pinnately compound leaves have 4 to 8 paired leaves per rachis.
 Paloverdes are legumes and thus produce elongated seed  pods.  To differentiate these two legumes: the seed pod of C. microphyllum has distinct indentations along the fruit that seem to squeeze sections into a natural constriction. Look for differences in the pinnately compound leaves. Overall, the branches of this legume are straighter, more erect, while droopy in C. floridum.
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BLUE PALOVERDE (Cercidium floridum)
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 This is a far less common desert legume than C. microphyllum; it is also much bluer in coloration. The flowers have five petals; four are yellow but one has a splash of orange.
 Look for spines at the base of the leaves, that are twice pinnately compound and have only one to three leaf pairs per rachis.
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IRONWOOD  (Olneya tesota)
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 Another desert legume, this tree can reach 40-45 ft.  A favorite habitat is dry washes that are soaked periodically.   It has a very dense wood that sinks in water and is highly resistant to decay, which explains its desirability when long use-life is required. There are claims that the wood has persisted for 1,500 years.  As with most desert legumes, Olneya has the ability to convert nitrogen in the air to a form usable for plant and animal growth.
 The leaves are twice-pinnately compound. The flowers, lavender to pink, can cover the entire tree in spectacular color.
 
 
 
 
 

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VELVET MESQUITE (Prosopis velutina)
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 Another abundant leguminous tree, it has a brown bark that cleaves into narrow strips. The wood is highly desired in cooking and other uses.
 Flowers occur as a slender, cylindrical, yellow mass. The leaves are twice pinnately compound. A favorite habitat is where ever adequate water is available.  However, this is a classical "phreatophyte" which means its roots can penetrate deeply into the soil in search of a permanent watertable.
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DESERT WILLOW (Chilopsis linearis)
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 A large scrub to small tree that often reclines. Leaves opposite, simple, linear to linear-lanceolate with entire margins. A deciduous tree, it drops its foliage during the winter. Petals are white with yellow spots in the interior. Fruit is a slender, elongated, thin-walled capsule that split to form to curved segments that persists on the tree.
 Another intolerant desert   plant that favors open areas.
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Cacti are not some mysterious group of plants that evolved autonomously in response to the environmental limitations under which they must live and prosper.  Everyone is reasonably familiar with a typical leaf-bearing forest tree such as a maple, or oak. All cacti evolved from such woody plants; indeed it is believe that woody plants of the genus; Pereskia are a living bridge between woody plants and cacti.
 If you look at a fallen suguaro, the first thing one notes is the large woody ribs running the length of the barrel (Figure 1).  The barrel is the equivalent of the  “stem” of a maple tree and the woody ribs of the suguaro are very much like the solid woody tissues of the maple.  Massive amounts of softer tissue surround the woody ribs and these tissues, responsible for transport of nutrients throughout the plant, perform the same function in both the suguaro and the maple. “So, what happened to the green leaves of the maple?” you may reasonably ask.
 Cacti do not possess leaves and their loss was a major adaptation to the scarcity and often-poor distribution pattern of desert rains.  Why the loss of these leafy appendages?  Maple leaves are permeated with a vast numbers of minute openings (stomates) through which carbon dioxide gas enters the plant. This gas is the primary building block for making essential sugars and other plant compounds.  The maple leaf also houses tiny, bodies (chloroplasts) that contain chlorophylls. Chlorophylls are light-gathering pigments that trap the energy of sunlight, for use in the energy-demanding process of converting carbon dioxide to foodstuffs (photosynthesis). Chlorophylls are responsible for the distinct green coloration of the leaf.
If the plant is to rid itself of large leaves and thereby avoid the loss of water through the stomates, while they are open to take in carbon dioxide, the chloroplasts have to be moved somewhere else. Eventually, the chloroplasts came to reside in the stem of a cactus, where they conduct photosynthesis. Indeed, all functions of photosynthesis have been successfully passed to the non-leafy tissues, which are far more water- conserving tissue systems.
In the foothills paloverde, Cercidium microphyllum, and the blue paloverde, Cercidium floridum, for example, the chloroplasts were also passed to the branches to create the “green tree” that the Spanish named paloverde. (Figure 2).  In the prickly pear (Opuntia engelmannii), photosynthesis is conducted in the pads-modified flower stalks (Figure 3). Water loss by this strategy is not totally avoided but it is greatly reduced. As part of this adaptation, cacti lost the bark tissues of a forest tree. The presence of these tissues would obstruct the absorption of radiant energy by the green stems.
Another water conserving  strategy of many desert plants is to open the stomates in the cool of the night and trap the carbon dioxide as storage compounds.  During the day, when the chloroplasts are absorbing the radiant energy, these storage compounds release carbon dioxide that was taken in the cool of the night, not the heat of the day. By this means, the plant avoids opening its stomates for carbon dioxide during the hottest parts of the day. Thus, emerges still another fascinating example of desert-plant adaptation to the environmental extremes under which they are forced to survive.
Maples and cacti both produce a root system that is responsible for uptake from the soil of water and essential nutrients. But maples grow much of their roots straight down and deep, so as to anchor the plant with great tenacity.  Many cacti rely more extensively on a lateral root system, able to secure every morsel of available water. Roots spreading far and wide but not as deep  is the price paid to maximize water uptake. The downside is that it is not unusual to see even a mature saguaro readily toppled in a strong desert rainstorm. This feature of employing an extensive, lateral root system is also seem in various barrel cacti that are also found prostrate on the desert floor with their seemingly feeble root system largely exposed. (Figure 4).
In a maple tree, the leaves develop from a lateral growing center or “bud”, a structure packed with cells capable of growth and development. In a cactus, these buds evolved into the “areole” from which the spines developed and protrude.  It is the presence of the areole, above all else, that is the quintessential, defining structure of all cacti. Thus simply speaking, the bud and the leaf of the woody trees of our great forests have become the areoles and spines of the desert cacti. Some cacti, particularly members of the genus: Opuntia (Cylindropuntia) developed additional structures known as “glochids” that, by virtue of their irritating fine hairs, afford protection from animals that would otherwise consume the fleshy “pads” of these cacti (Figure 5). Chollas are unique for they are the only cacti with papery sheaths that enclose the spines as well as tubercles: small projections on the stem that support the areoles and spines.
Opuntia.  Amongst the most ubiquitous of the Sonoran desert cacti are members of the genus: Opuntia. This assemblage of plants, containing about 20 species, includes the chollas: cacti with cylindrical stems or branches constructed of individual joined segments. Most noteworthy are the jumping chollas: the teddy bear cholla (Opuntia bigelovii) and the chain fruit cholla (Opuntia fulgida).  These “jumping” cholla are aptly named because they seem to “jump out and grab onto” every passing person. Easy release of segments of these cacti is essential because these cacti, to an overwhelming extent, reproduce asexually.
Asexual reproduction means that rather than relying upon fertilization between the pollen grain and ovule and the resulting mixing of male and female genes, the offspring develops solely from genetic  materials (genome) of the mother plant. These cacti facilitate reproduction by developing a barb that improves plant dispersal by attaching to a passing animal, as well as anchoring the dropped segment into the desert soil to grow into a new, independent plant. No new genetic material is introduced in this process; the daughter is an exact copy (clone) of the mother plant.  This method of reproduction explains why often jumping chollas occur in highly clustered groups. (Figure 6).
Other chollas include the very common, staghorn cholla (Opuntia versicolor) and buckhorn cholla (Opuntia acanthocarpa) and the less common desert inhabitants: the Christmas cholla (Opuntia leptocaulis), and the pencil cholla (Opuntia arbuscula). All of these cacti share the common characteristic of jointed stems.
The remaining members of the Opuntia have conspicuous pads that look like paddles projecting from the flower stalk. The most abundant of this group is the Engelmann prickly pear, Opuntia engelmanii.
 Saguaro. The stately giant saguaro, Carnegeia gigantea, is the signature plant of the Sonoran desert.  Starting from the tiniest of seeds, it grows into a stately plant that can reach 2 feet in diameter and 40-45 feet in height.  Most saguaro begin life in the shade and protection of another plant, often a desert legume such as a paloverde or an ironwood or a suitable scrub.  This “mother plant” offers a protective environment for the baby cactus (Figure 7). On the other hand, the young saguaro can grow successfully in the open (Figure 8).
 The cactus body is wholly green, indicating its food-producing function, and the columnar stem is fluted heavily. This fluted construction facilitates expansion and contraction in response to water availability. This plant is capable of absorbing prodigious quantities of water, resulting in a body mass increase well in excess of a thousand pounds. The areoles and spines are located along the ridges of the stem.
 Conventional wisdom states that around 75 years of age, C. gigantea develops stately arms. Arm production continues throughout the life of the plant-generally on the order of 150-200 years. Five to ten arms is commonplace, but on occasion one finds much greater numbers (Figure 9).
 Like virtually all desert cacti, the root system of this behemoth is not that extensive.  It does not produce a deep taproot. as it only extends about three feet into the soil. Instead, a large system of radial roots, permitting water uptake over an extensive area, is formed.  These lateral roots can reach out nearly 100 feet from the stem.  This evolutionary adaptation for water procurement leaves the saguaro vulnerable. During the heavy rains of the winter of 2005, I personally noted some dozen fully matured saguaros mortally uprooted.
 A great sight for the desert dweller is the appearance of saguaro flowers in early summer. These flowers always arise from flower buds positioned at the apex of the main stem and side arms of the cactus. A series of creamy-white petals surround the yellow stamens to create a distinctive and beautiful flower (Figure 10). Since this cactus cannot self-pollinate, great effort is extended in creating a sweet, sought after nectar that attracts various birds, an array of insects, and even bats to the flower. They act subsequently as vectors in pollen dispersal to another flower. Saguaro flowers open during the cooler times at night and close with the heat of the new day. These flowers are truly ephemeral and wither within a day of opening.
 The fertilized flower gives rise to a succulent fruit (cylindrical berry) that splits open to reveal thousands of tiny, black seeds within its pulp, all housed within the scarlet-red walls of the fruit.   It is a clear visual clue to suitable animals to “come eat the seeds”. Such feeding activity results ultimately in successful seed dispersal through eventual release of non-digested seeds during defecation. Seeds develop quickly, there isn’t a period of weathering or leaching to initiate germination. Some authorities contend that bird roosting on nearby trees and their defecation from its branches places saguaro seeds in the protective surrounding of the “mother plant”. This is certainly a plausible idea.
 Barrel Cacti.  After the giant saguaro, the various barrel cacti are the most massive of the desert cacti.  These plants, belonging to the genus: Ferocactus (fierce or wild cactus) occur most often either as the fishhook barrel, Ferocactus wizlizenii and the more massive, compass barrel cactus: Ferocactus cylindraceus. Barrel cacti have massive, cylindrical or barrel-shaped stems, with many prominent ribs; they are protected with great effectiveness by strong, sharply pointed spines that can be curved like a fishhook. Indeed, they have been used for exactly this purpose.  When young, they are highly spherical but attain their columnar appearance with age. Central spines are often red, shading to gray, and the radial spines are bristle-like and gray.
 Flower development occurs from growing centers that are always located at the top of the stem. Most barrel cactus display great variation in flower color ranging from yellow-green through orange and yellow to red flowers that bloom generally in the summer months.  A yellow, barrel-shaped, scaly fruit is produced subsequently that is persistent and offers a long-term food resource for deer, rodents and other animals.
 Barrel cacti incline to the southwest due to differential growth; this causes a distinct lean in the stem that favors toppling and loss of the plant for the same reasons described for the saguaro; it is not unusual to see many barrel cacti that have succumbed after  being toppled and uprooted.
 Hedgehog Cacti. This group of cacti, comprising about three dozen species, readily hybridizes. That is, progeny can have properties of either parent.  Hedgehogs belong to the genus: Echinocereus.  This is not a solitary cactus, but rather occurs as cluster of erect stems that are cylindrical.  The stems bears areoles with very long, sharply pointed spines; spines production is extensive and they effectively protect the entire organism.
 Engelmann’s hedgehog, Echinocereus engelmannii is the most abundant of this group in the Sonoran desert. Flowers are brightly colored purple to lavender. Other hedgehog cacti range in flower color from green to yellow, pink, orange and red. These “cup” shaped flowers remain open all day long.
 Pinchusion and  Fishhook Cacti.  The cacti described above have distinct ribs that support the areoles and spines.  Pinchusion cacti grouped within the genus: Mammillaria lack ribbing. Instead,  spines project from tubercles, raised areas upon which the areole occur. Their spines can be straight (pinchusion cacti) or curved (fishhook cacti) and typically they are numerous in number-virtually covering the entire stem.  The limited central spines are the largest; lateral spines are smaller but far more abundant. Pinchusion spines are elongated and soft; this creates the illusion that the stem is covered in soft hairs. This group is also unique in that often the flowers emerge as a ring that encircles the stem
 
 
 

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SUGUARO  (Carnegeia gigantea)
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FISHHOOK BARREL (Ferocactus wenlizenii)
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COMPASS  BARREL (Ferocactus cylindraceus)
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TEDDY BEAR CHOLLA   (Opuntia bigelovii)
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CHAINFRUIT CHOLLA  (Opuntia fulgida)
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CHRISTMAS CACTUS  (Opuntia leptocaulis)
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BUCKTHORN CHOLLA (Opuntia acanthocarpa)
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STAGHORN CHOLLA (Opuntia versicolor)
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ENGELMANN PRICKLY PEAR  (Opuntia engelmannii)
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FISHHOOK CACTUS (Mammillaria grahamii)
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Yuccas are not cacti; they do not grow areoles or spines.  The genus: Yucca  contains  some of the most interesting plants of the Sonoran desert.  Yuccas have evolved a fascinating symbiotic relationship with desert moths; these insects are responsible for transporting pollen from one flower to another. Yuccas cultivated in the Old World, where yucca moths are absent, will not produce seeds unless they are hand-pollinated.
The yucca produces conspicuous, creamy-white blossoms that are part of an extended, erect inflorescence. Individual yucca flowers have six fleshy petal-like pieces. Some authorities call then “tepals” since the petals and sepals are indistinguishable.
 Each yucca plant has a special mutualistic relationship with one and only one species of yucca moth. Flowers of a given yucca plant produce a fragrance that is irresistible to a particular moth.  The yucca moth gains the nutritional benefits provided by the sugar-rich nectar-its reward. Yucca pollen is not dispensed as individual pollen grains. Instead that produce a sticky materials that cause the pollen to form a large mass known as a pollinia, while still within the anther. A female yucca moth collects these pollinia and then employs a prehensile appendage to produce a massive pollen mound which she faithfully transports to another plant of that species for fertilization. The large pollen ball is inserted into a deep cavity located by the pistil. At the same time, the female moth oviposits her eggs into the ovary.  The ovarial tissues act as a food resource for the emerging larvae. However, not all of the ovules are consumed, sufficient numbers remaining to provide seeds for the next generation of yuccas.
 This is a classical example of mutualism: mutual benefit to both parties. The female moth gains sustenance from the flower and is assured of adequate food for her emerging brood. The yucca flower is also a big winner. Its pollen is not carried just anywhere and potentially wasted; rather, it goes only to another fertilizable flower. The specificity of this relationship: one yucca plant-one yucca moth insures that the pollen is not transported haphazardly. This is a critical point; pollen goes only to a flower of the same species. Such limitation in the flowers that the yucca moth will visit enhances significantly the overall effectiveness of floral pollination. Development of such a close, specific relationship is one of the great examples of two organisms have evolved in response to mutual needs.
 Soaptree yucca (Yucca elata) leaves have considerable nutritional value and are sought actively by many desert animals. Woodrats love this plant, they remove the leaves at their base, and use this material both as food source and for nest-building material  (Figure 10).
 Cattle, deer, pronghorn antelope and other herbivores nibble on the leaves and relish the succulent young flower stalks. Orioles and cactus wrens construct their nests deep in the dense leaf bundles. Yuccas have sufficient height to provide perches for hunting shrikes and hawks. The name soaptree yucca results from the production of an interesting plant chemical called saponins. These materials can create a cleansing lather-much like soap.

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SOAPTREE YUCCA (Yucca elata)
 Family: Agavaceae
_____________________________________________________________________________ Normally, shrub-sized, it can reach 20 ft in height and 8 inches in diameter. Leaves are alternate; simple; flat on the surface, but curved beneath. Yellow-green, narrow leaves, when young have margins that are entire, but quickly split into slender, whitish strips that concentrate in the center of the plant. Leaves, highly fibrous, which adds great strength, coupled with its sharp pointed apex led to its alternate common name: Spanish-bayonet.
 Ivory-white, cup-shaped flower made from six ovate petal-like structures, six stamens and a hexagonal, three-segmented ovary.  Yucca elata fruit is an erect, oblong three-segmented capsule. This fruit is filled with black, edible seeds. Woody and therefore persistent,  fruit capsules from a prior year often hangs above the plant.
 This is an intolerant plant that means that it favors open areas with full light. An aggressive competitor in disturbed areas, it is an excellent indicator of heavy grazing or other prior environmental damage. The dried leaves are important in Indian basketry.
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BANANA YUCCA  (Yucca baccata
 Family: Agavaceae
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 Heavy, stout plant that can reach six feet with long, sharp foliage. Dead  foliage remains on the plant forming a dense mat at the base. Blue-green leaves are long and rigid, sharply points and much heavier than that of Y. elata.
 Flower creamy-white tinged with green tissues at the base and central line of the outside of the petal. Sepals and petals in threes. Six staments with white filaments, anthers curved at their apex, stigma yellow. Pistil, tubular, pointed with ridges.
Fruit is a green cylindrical capsule housing black seeds.  Flower and seed production requires considerable resource allocation; perhaps, explaining why this plant does not set seed annually. Interestingly, animals are responsible for opening the capsules and dispensing the seeds.
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Ocotillo. Ocotillos are unique and fascinating plants. They appear to be cactus-like because of their elongated spines, reduced foliage and general appearance. However, this plant produces true leaves that remain on the flower stalk as long as water is plentiful. Onset of water stress induces leaf fall; with the return of favorable soil moisture conditions,  a new crop of leaves emerge.
The ocotillo is the sole member of the genus: Fouquieria and the only local member of the family (Fouquieriaceae) to which it belongs. (Just as species with common genetic characteristics are lumped into a genus; so too, are genera with similar genetic trails are grouped into a “family” unit). This is most unusual because a family is a fairly advanced taxonomic level that can contain hundreds, even thousands of individual species. There are some 18,000 members of the bean family (Fabaceae) and at least 20,000 in the sunflower family (Asteraceae).
Ocotillos sprout roots easily; stems pushed into the ground can and do grow into a viable plant. Their massive bulk, spreading arms, and vivid red flower heads produce a visually striking desert dweller (Figure 11).
Ocotillo has an open growth form created by numerous slender woody stems that project from the base of the plant. The stems are interesting because much of the year they are without leaves. When adequate rainfall occurs, new leaves rapidly sprout, but they disappear just as quickly when water levels fall beyond a certain point. Some tissues of the lost leaf remain on the stem and it is from these persistent tissues that the new crop of leaves develope.
Ocotillo flowers are tubular and bright red, signs that indicate their potential association with hummingbirds. This is a stimulating color and shape to these perpetually moving avians.  Another important pollinator appears to be carpenter bees who overcome the lack of a large, probing mouthparts by moving over the petal and piercing the flower tube to secure its nectar. The flowers also are eaten by ants and antelope ground squirrels.
 Ephedra. Ephedra are among the most unexpected of the desert plants. At the low elevations and long, hot growing season of the Sonoran desert, one does not see, nor expect to see, plants such as pine, spruce, or fir-these are all conifers. Conifers are commonly known as evergreen plants because of their apparent lack of foliage loss at the end of the growing season (actually, foliage loss does occur). Conifers or gymnosperms are an ancient lineage of plants that produce relatively inconspicuous reproductive structures (note that I did not use the word: flower because they do not produce flowers such as those described in this work).  Gymnosperm seeds are borne naked and exposed in the interior of a cone. Flowering plants are angiosperms-flowering plants whose seeds are borne protected inside a fruit.
 What makes members of the genus: Ephedra so fascinating is that they are gymnosperms. Their seeds are borne exposed in a small cone-like structure (Figure 12). Leaves are reduced to tiny dark scales at the joints and photosynthesis takes place in the green stem. Ephedra is another example of a dioecious plant: one that has both “male” and “female” flowers on separate plants
The main active medical ingredients in Ephedra are the alkaloids: ephedrine and pseudoephedrine (many plant alkaloids have potent pharmacological properties). Ephedrine is chemically similar to adrenaline in its ability to excite the central nervous system. It stimulates the heart, causing increased blood pressure and heart rate and is an effective bronchodilator. It can stimulate contraction of the uterus and has diuretic properties. Because it constricts peripheral blood vessels, it can relieve congestion in mucous tissues. Pseudoephedrine has a weaker cardiac effect but a greater diuretic activity. Teas made from these plants can cause constipation as a result of their tannin content.
The stem contains 1-3% total alkaloids, with ephedrine accounting for 30-90% of this total. There is significantly variability in the amount of these alkaloids in any given plant and they must be consumed with great care since they possess potentially lethal stimulatory effects on the central nervous system and heart.
This plant has found use as a general stimulant and it is also a bronchial dilator useful in the treatment of asthma. The name mormon tea associated with Ephedra plants came from its use by early Mormon pioneers as a general stimulant during their physically demanding journey across western America.
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OCOTILLO  (Fouquieria splendens)
 Family: Fouquieriaceae
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 Multiple stems emanate from a common basal region. Leaf petioles modified into a sharp, armored thorn. Spatula-shaped leaves are ephemeral, falling in response to drought or cold conditions.
 Flowers are elongated, tubular and bright crimson; clustered at stem tip. Ovoid capsules house winged, wind-dispersed seeds.
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MORMON TEA (Ephedra spp.)
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 Stems are green, jointed and leafless. Minute pale yellow "flowers" produce a dense cluster of papery cones. Stems were harvested and used to make an infusion that acted as a stimulant due to the presence of potent alkaloids.
Ephedra nevadensis and other local members, lacking potent pharmacological  compounds,  have been made into a refreshing, non-stimulating beverages used to treat venereal diseases. The fruits of some species are eaten, while ashes of E. intermedia are mixed with chewing tobacco in Pakistan.
 
 

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 DESERT MISTLETOE  (Phoradendron californica)
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A semi-parasitic plant typically found on acacia, mesquite, ironwood, and paloverdes. It forms a large, clustered mass that typically hangs from a host tree branch.
Leaves diminutive reduced to scale-like structures.  Another dioecious species, only the female mistletoe bears white, globose berries that turn red.
 A green, chlorophyll-laden stem reveals an ability to produce its own foodstuffs by photosynthesis; host water and nutrients are taken by living parasite tissues that grow into the body of the host plant.
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