Saguaro

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Saguaro
Saguaro National Park near Tucson, Arizona during November (58).jpg
Scientific classification Red Pencil Icon.png
Kingdom: Plantae
Clade: Angiosperms
Clade: Eudicots
Order: Caryophyllales
Family: Cactaceae
Subfamily: Cactoideae
Tribe: Echinocereeae
Genus: Carnegiea
Britton & Rose
Species:
C. gigantea
Binomial name
Carnegiea gigantea
(Engelm.) Britton & Rose
Carnegiea gigantea range map 3.png
Natural range of Carnegiea gigantea
Synonyms [2]
  • Cereus giganteusEngelm.
  • Pilocereus engelmanniiLem.
  • Pilocereus giganteusRumpler

The saguaro ( /səˈwɑːr/ , Spanish pronunciation:  [saˈɣwaɾo] ) (Carnegiea gigantea) is an arborescent (tree-like) cactus species in the monotypic genus Carnegiea, which can grow to be over 40 feet (12 m) tall. It is native to the Sonoran Desert in Arizona, the Mexican State of Sonora, and the Whipple Mountains and Imperial County areas of California. The saguaro blossom is the state wildflower of Arizona. Its scientific name is given in honor of Andrew Carnegie. In 1994, Saguaro National Park, near Tucson, Arizona, was designated to help protect this species and its habitat.

Cactus Family of mostly succulent plants, adapted to dry environments

A cactus is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1750 known species of the order Caryophyllales. The word "cactus" derives, through Latin, from the Ancient Greek κάκτος, kaktos, a name originally used by Theophrastus for a spiny plant whose identity is not certain. Cacti occur in a wide range of shapes and sizes. Most cacti live in habitats subject to at least some drought. Many live in extremely dry environments, even being found in the Atacama Desert, one of the driest places on earth. Cacti show many adaptations to conserve water. Almost all cacti are succulents, meaning they have thickened, fleshy parts adapted to store water. Unlike many other succulents, the stem is the only part of most cacti where this vital process takes place. Most species of cacti have lost true leaves, retaining only spines, which are highly modified leaves. As well as defending against herbivores, spines help prevent water loss by reducing air flow close to the cactus and providing some shade. In the absence of leaves, enlarged stems carry out photosynthesis. Cacti are native to the Americas, ranging from Patagonia in the south to parts of western Canada in the north—except for Rhipsalis baccifera, which also grows in Africa and Sri Lanka.

In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. While these definitions may seem adequate, when looked at more closely they represent problematic species concepts. For example, the boundaries between closely related species become unclear with hybridisation, in a species complex of hundreds of similar microspecies, and in a ring species. Also, among organisms that reproduce only asexually, the concept of a reproductive species breaks down, and each clone is potentially a microspecies.

A genus is a taxonomic rank used in the biological classification of living and fossil organisms, as well as viruses, in biology. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus.

Contents

Some saguaros are cristate or "crested" due to fasciation. Crested Saguaro cactus.jpg
Some saguaros are cristate or "crested" due to fasciation.
A house sparrow nesting on a saguaro cactus House Sparrow nesting in saguaro cactus.JPG
A house sparrow nesting on a saguaro cactus

Saguaros have a relatively long lifespan, often exceeding 150 years. They may grow their first side arm any time from 75–100 years of age, but some never grow any arms. A saguaro without arms is called a spear. Arms are developed to increase the plant's reproductive capacity, as more apices lead to more flowers and fruit.

Flower Structure found in some plants; aka: blossom

A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants. The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs. Flowers may facilitate outcrossing or allow selfing. Some flowers produce diaspores without fertilization (parthenocarpy). Flowers contain sporangia and are the site where gametophytes develop. Many flowers have evolved to be attractive to animals, so as to cause them to be vectors for the transfer of pollen. After fertilization, the ovary of the flower develops into fruit containing seeds.

Fruit part of a flowering plant

In botany, a fruit is the seed-bearing structure in flowering plants formed from the ovary after flowering.

A saguaro is able to absorb and store considerable amounts of rainwater, visibly expanding in the process, while slowly using the stored water as needed. This characteristic enables the saguaro to survive during periods of drought. The saguaro cactus is a common image in Mexican culture and American Southwest films.

Drought extended period when a region notes a deficiency in its water supply

A drought or drouth is a natural disaster of below-average precipitation in a given region, resulting in prolonged shortages in the water supply, whether atmospheric, surface water or ground water. A drought can last for months or years, or may be declared after as few as 15 days. It can have a substantial impact on the ecosystem and agriculture of the affected region and harm to the local economy. Annual dry seasons in the tropics significantly increase the chances of a drought developing and subsequent bush fires. Periods of heat can significantly worsen drought conditions by hastening evaporation of water vapour.

Description

The saguaro is a columnar cactus that grow notable branches, usually referred to as arms. As many as 25 arms may grow on one plant. They are slow growing but routinely live to 150 or 200 years old. They are the largest cactus in the United States. Their roots are shallow yet wide, growing only to 6 inches (150 mm) deep, but extend as wide as the plant is tall. [3]

The growth rate of saguaros is strongly dependent on precipitation; saguaros in drier western Arizona grow only half as fast as those in and around Tucson. Saguaros grow slowly from seed, never from cuttings, and grow to be over 40 feet (12.2 metres) in height. [4] The largest known living saguaro is the Champion Saguaro growing in Maricopa County, Arizona, measuring 45.3 feet (13.8 metres) high with a girth of 10 feet (3.1 metres). The tallest saguaro ever measured was an armless specimen found near Cave Creek, Arizona. It was 78 feet (23.8 metres) in height before it was toppled in 1986 by a windstorm. [5] When rain is plentiful and the saguaro is fully hydrated it can weigh between 3,200–4,800 pounds (1,500–2,200 kg).[ citation needed ]

Arizona state of the United States of America

Arizona is a state in the southwestern region of the United States. It is also part of the Western and the Mountain states. It is the sixth largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona shares the Four Corners region with Utah, Colorado, and New Mexico; its other neighboring states are Nevada and California to the west and the Mexican states of Sonora and Baja California to the south and southwest.

Tucson, Arizona City in Arizona, United States

Tucson is a city and the county seat of Pima County, Arizona, United States, and home to the University of Arizona. The 2010 United States Census put the population at 520,116, while the 2015 estimated population of the entire Tucson metropolitan statistical area (MSA) was 980,263. The Tucson MSA forms part of the larger Tucson-Nogales combined statistical area (CSA), with a total population of 1,010,025 as of the 2010 Census. Tucson is the second-largest populated city in Arizona behind Phoenix, both of which anchor the Arizona Sun Corridor. The city is 108 miles (174 km) southeast of Phoenix and 60 mi (97 km) north of the U.S.–Mexico border. Tucson is the 33rd largest city and the 58th largest metropolitan area in the United States (2014).

Cave Creek, Arizona Town in Arizona, United States

Cave Creek is a town in Maricopa County, Arizona, United States. The largest city it borders is Phoenix, Arizona. According to the 2010 census, the population of the town was 5,015.

Spines

Saguaro spines Carnegiea gigantea trunk - close up (6989395593).jpg
Saguaro spines

The spines on a saguaro can grow up to 1 millimetre (0.039 in) per day. When held up to the light or bisected, alternating light and dark bands transverse to the long axis of spines can be seen. These transverse bands have been correlated to daily growth. In columnar cacti, spines almost always grow in areoles which originate at the apex of the plant. A spine stops growing in its first season. Areoles are moved to the side and the apex continues to grow upwards. Thus, older spines are towards the base of a columnar cactus and newer spines are near the apex. Studies are underway to examine the relationship of carbon and oxygen isotope ratios in the tissues of spines of an individual to its climate and photosynthetic history (acanthochronology). [6]

Isotope nuclides having the same atomic number but different mass numbers

Isotopes are variants of a particular chemical element which differ in neutron number, and consequently in nucleon number. All isotopes of a given element have the same number of protons but different numbers of neutrons in each atom.

Photosynthesis Biological process to convert light into chemical energy

Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that can later be released to fuel the organisms' activities. This chemical energy is stored in carbohydrate molecules, such as sugars, which are synthesized from carbon dioxide and water – hence the name photosynthesis, from the Greek φῶς, phōs, "light", and σύνθεσις, synthesis, "putting together". In most cases, oxygen is also released as a waste product. Most plants, most algae, and cyanobacteria perform photosynthesis; such organisms are called photoautotrophs. Photosynthesis is largely responsible for producing and maintaining the oxygen content of the Earth's atmosphere, and supplies all of the organic compounds and most of the energy necessary for life on Earth.

Acanthochronology

Acanthochronology is the interdisciplinary study of cactus spines or Euphorbia thorns grown in time ordered sequence. Physical, morphological or chemical characteristics and information about the relative order or absolute age of the spines or thorns is used to study past climate or plant physiology.

Flowers

Saguaro flowers Carnegiea gigantea (Saguaro cactus) blossoms.jpg
Saguaro flowers

The white, waxy flowers appear in April through June, opening well after sunset and closing in mid-afternoon. They continue to produce nectar after sunrise. [7] Flowers are self-incompatible, thus requiring cross-pollination. Large quantities of pollen are required for complete pollination because many ovules are present. This pollen is produced by the extremely numerous stamens, which in one notable case totaled 3,482 in a single flower. [8] A well-pollinated fruit contains several thousand tiny seeds. Saguaros have a redundant pollination system, i.e. full fruit set is possible even if only a fraction of the pollinating species are present.

Main pollinators are honey bees, bats, and white-winged doves. In most years, diurnal visitors, mostly honey bees, are the main contributors for fruit. Other diurnal pollinators are birds such as Costa's hummingbird, the black-chinned hummingbird, the broad-billed hummingbird, the hooded oriole, Scott's oriole, the Gila woodpecker, the gilded flicker, the verdin, and the house finch. [9]

The primary nocturnal pollinator is the lesser long-nosed bat, feeding on the nectar. A number of floral characteristics are geared toward bat pollination: nocturnal opening of the flowers, nocturnal maturation of pollen, very rich nectar, position high above ground, durable blooms that can withstand a bat's weight, and fragrance emitted at night. Further, the amino acids in the pollen appear to help sustain lactation in bats.

Fruit

Bird perched atop fruits at the tip of a saguaro Saguaro cactus fruits with bird.jpg
Bird perched atop fruits at the tip of a saguaro
Maricopa women gathering saguaro fruits, photo by Edward S. Curtis, 1907 Saguaro gatherers2.jpg
Maricopa women gathering saguaro fruits, photo by Edward S. Curtis, 1907

The ruby red fruits are 2.4 to 3.5 inches (6 to 9 cm) long and ripen in June, each containing around 2,000 seeds, plus sweet, fleshy connective tissue. The fruits are edible and prized by local people.

The fruits are often out of reach and are harvested using a pole (often a saguaro rib) 7 to 16 feet (2 to 5 m) long, to the end of which is attached a smaller pole, crosswise. This pole is used to knock the fruits free.

The O'odham tribes have a long history of saguaro fruit use. [10] The Tohono O’odham tribes celebrate the beginning of their summer growing season with a ceremony using a fermented drink made from the bright red fruit, to summon rains vital for their crops.

Genome

The saguaro genome is around 1 billion base pairs long. [11] Sequencing has revealed that the genome of the saguaro's chloroplast is the smallest known among non-parasitic flowering plants. [12]

Distribution and habitat

Saguaros are endemic to the Sonoran Desert and are found only in western Sonora in Mexico and in southern Arizona in the US although plants are occasionally found in southeastern California. Elevation is a limiting factor to its environment, as the saguaro is sensitive to extended frost or cold temperatures. [3] No wild saguaros are found anywhere in New Mexico, Texas, Colorado, Utah, or Nevada, nor in the high deserts of northern Arizona. [13]

Nests

Native birds such as Gila woodpeckers, purple martins, house finches, and gilded flickers live inside holes in saguaros. Flickers excavate larger holes higher on the stem. [14] The nest cavity is deep, and the parents and young are entirely hidden from view. The saguaro creates callus tissue on the wound. When the saguaro dies and its soft flesh rots, the callus remains as a so-called saguaro boot, which was used by natives for storage.

The Gila woodpeckers (Melanerpes uropygialis) create new nest holes each season rather than reuse the old ones, leaving convenient nest holes for other birds, such as elf owls, flycatchers, and wrens. [15] In recent years, early-breeding, aggressive, non-native birds have taken over the nests to the detriment of elf owls that breed and nest later.

Conservation

Harming or vandalizing a saguaro in any manner, such as shooting them (sometimes known as 'cactus plugging') [16] is illegal by state law in Arizona. When houses or highways are built, special permits must be obtained to move or destroy any saguaro affected. [17] Exceptions to this general understanding exist; for example, a private landowner whose property is 10 acres (4.0 ha) or less, where the initial construction has already occurred, may remove a saguaro from the property. [18] This is common when the cactus falls over in a storm, its location interferes with a house addition, or it becomes a potential hazard to humans. [19]

In 1982, a man was killed after damaging a saquaro. David Grundman was shooting and poking at a saguaro cactus in an effort to make it fall. An arm of the cactus, weighing 500 pounds (230 kg) fell onto him, crushing him and his car. The trunk of the cactus then also fell on him. [16] [20] The Austin Lounge Lizards wrote the song "Saguaro" about this death. [20]

Contrary to published statements, [21] there is no law mandating prison sentences of 25 years for cutting a cactus down; however it is considered a class four felony with a possible 3 year, 9 month maximum sentence. [22]

Ethnobotany

In culture

The saguaro is often used as an emblem in commercials and logos that attempt to convey a sense of the Southwest, even if the product has no connection to Arizona or the Sonoran Desert. For instance, no naturally occurring saguaros are found within 250 miles (400 km) of El Paso, Texas, but the silhouette is found on the label of Old El Paso brand products. [23] [13] Though the geographic anomaly has lessened in recent years, Western films once enthusiastically placed saguaros in the Monument Valley of Arizona, as well as New Mexico, Utah, and Texas. The Dallas, Texas-based band, Reverend Horton Heat, pokes fun at this phenomenon in their song "Ain't no Saguaro in Texas". [24]

Related Research Articles

Sonoran Desert North American desert

The Sonoran Desert is a North American desert which covers large parts of the Southwestern United States in Arizona and California and of Northwestern Mexico in Sonora, Baja California, and Baja California Sur. It is the hottest desert in Mexico. It has an area of 260,000 square kilometers (100,000 sq mi). The western portion of the United States–Mexico border passes through the Sonoran Desert.

Barrel cactus

Barrel cacti are various members of the two genera Echinocactus and Ferocactus, found in the deserts of Southwestern North America. Some of the largest specimens can be found in the Mojave Desert in southern California.

Gila woodpecker species of bird

The Gila woodpecker is a medium-sized woodpecker of the desert regions of the southwestern United States and western Mexico. In the U.S., they range through southeastern California, southern Nevada, Arizona, and New Mexico.

<i>Cylindropuntia bigelovii</i> species of plant

Cylindropuntia bigelovii, the teddy bear cholla(choy-ya), is a cholla cactus species native to Northwestern Mexico, and to the United States in California, Arizona, and Nevada.

Yuma Desert

The Yuma Desert is a lower-elevation section of the Sonoran Desert in the southwestern United States and the northwest of Mexico. It lies in the Salton basin. The desert contains areas of sparse vegetation and has notable areas of sand dunes. With an average rainfall less than 8 inches (200 mm) each year, this is among the harshest deserts in North America. Human presence is sparse throughout, the largest city being Yuma, Arizona, on the Colorado River and the border of California.

<i>Pachycereus pringlei</i> species of plant

Pachycereus pringlei, also known as Mexican giant cardon or elephant cactus, is a species of cactus native to northwestern Mexico in the states of Baja California, Baja California Sur, and Sonora. It is commonly known as cardón, a name derived from the Spanish word cardo, meaning "thistle".

Gilded flicker species of bird

The gilded flicker is a large-sized woodpecker of the Sonoran, Yuma, and eastern Colorado Desert regions of the southwestern United States and northwestern Mexico, including all of Baja California except the extreme northwestern region. Golden-yellow underwings distinguish the gilded flicker from the northern flicker found within the same region, which has red underwings.

<i>Ferocactus wislizeni</i> species of plant

Ferocactus wislizeni, the fishhook barrel cactus, also called Arizona barrel cactus, candy barrel cactus, and Southwestern barrel cactus, is a species of flowering plant in the cactus family Cactaceae, native to northern Mexico and the southern United States. It is a ball-shaped cactus eventually growing to a cylindrical shape, with spiny ribs and red or yellow flowers in summer.

Saguaro National Park United States National Park, in the state of Arizona

Saguaro National Park is an American national park in Pima County, southeastern Arizona. The 92,000-acre (37,000 ha) park consists of two separate areas—the Tucson Mountain District (TMD) about 10 miles (16 km) west of the city of Tucson and the Rincon Mountain District (RMD) about 10 miles (16 km) east of the city—that preserve Sonoran Desert landscapes, fauna, and flora, including the giant saguaro cactus.

<i>Neobuxbaumia polylopha</i> species of plant

Neobuxbaumia polylopha is found only in Mexico and is confined to a small area in the state of Guanajuato. It grows only in canyons with limestone slopes, similar to the cacti Neobuxbaumia multiareolata, Neobuxbaumia sanchezmejunadae, and Neobuxbaumia squamulosa. Neobuxbaumia polylopha is not well known among locals and has no local uses. However, it is popular among cactus enthusiasts and reproduces well in nurseries.

Saguaro boot

A saguaro boot is the hard shell of callus tissue, heavily impregnated with lignin, that a saguaro cactus creates to protect the wound created by a bird's nesting hole. The bird pecks through the cactus skin, then excavates downward to hollow out a space for its nest. When the saguaro dies, its soft flesh rots, but its woody infrastructure lasts much longer. So does the hollowed-out callus whose roughly boot-like shape gives it the name of "saguaro boot."

Lycium berlandieri is a species of flowering plant in the nightshade family known by the common name Berlandier's wolfberry. It is native to Mexico and the southwestern United States from Arizona to Texas.

<i>Echinocereus dasyacanthus</i> species of plant

Echinocereus dasyacanthus is a member of the cactus family, Cactaceae. It is one of about 2000 total species belonging to this family. The cactus is commonly known as Texas rainbow cactus because of the subtle rings or bands of contrasting colors along the stem of the plant. Not all Texas rainbow cacti have the "rainbow" coloration on their stems. Another common name is spiny hedgehog cactus.

<i>Pachycereus pecten-aboriginum</i> species of plant

Pachycereus pecten-aboriginum is a columnar cactus plant native to Mexico. They can grow up to 15 meters high. The trunk of this species is 1.2 to 5 meters tall and the fruits are large and burlike. The species name, pecten-aboriginum, is from the Latin, and means "native combs". It was inspired by the use of the fruits as hair combs.

Flora of the Sonoran Desert includes six subdivisions based on vegetation types. Two are north of the boundary between the United States and Mexico, and four are south of the boundary. The flora of the Colorado Desert are influenced by the environment of the very dry and hot lower areas of the Colorado River valley, which may be barren, treeless, and generally have no large cacti. Flora of the Arizona Upland are comparatively lush, with trees and large columnar cacti that can withstand winter frosts. South of the border subdivisions are characterized by plants that cannot withstand frost.

Flora of the Arizona Upland includes higher elevation Sonora Desert plants that require more moisture and cooler climates than those of the adjacent Sonoran Desert areas in the Colorado Desert of the lower Colorado River valley area, and which can withstand frost, unlike plants of the Sonoran Desert south of the border between the United States and Mexico.

Peniocereus striatus is a species of cactus known by several common names, including gearstem cactus, cardoncillo, jacamatraca, sacamatraca, and dahlia-rooted cactus. It is endemic to the Sonoran Desert, where it occurs in Baja California, Sinaloa, and Sonora in Mexico and Arizona in the United States.

References

Notes

  1. "The IUCN Red List of Threatened Species". IUCN Red List of Threatened Species. Retrieved 2018-10-26.
  2. "Carnegiea gigantea (Engelm.) Britton & Rose". Tropicos. Missouri Botanical Garden. Retrieved 2014-09-19.
  3. 1 2 3 4 "Saguaro Cactus Fact Sheet". www.desertmuseum.org. Retrieved 2019-03-27.
  4. "Life Cycle of the Saguaro" (PDF). Arizona-Sonora Desert Museum. 2008. Retrieved 2013-12-04.
  5. "Windstorm Fells 78-Foot Cactus--Tallest in World" . Retrieved 2015-08-04.
  6. English, N. B.; Dettman, D. L.; Sandquist, D. R.; Williams, D. G. (2007). "Past climate changes and ecophysiological responses recorded in the isotope ratios of saguaro cactus spines". Oecologia. 154 (2): 247. doi:10.1007/s00442-007-0832-x.
  7. Theodore H. Fleming: Sonoran desert columnar cacti and the evolution of generalized pollination systems. In: Ecological Monographs. Band 71, Number 4, 2001, pp. 511–530, JSTOR.
  8. SCIENCE Vol. 40 (November 6, 1914) p. 680.
  9. Theodore H. Fleming: Sonoran desert columnar cacti and the evolution of generalized pollination systems. In: Ecological Monographs. Band 71, Number 4, 2001, pp. 517–518, JSTOR.
  10. A Natural History of the Sonoran Desert, Edited by Steven J Phillips and Patricia Comus, University of California Press, Berkeley, 2000, p. 193
  11. "SGP5_Cgig_v1.3 - Genome - Assembly - NCBI". www.ncbi.nlm.nih.gov. Retrieved 24 April 2018.
  12. Sanderson, Michael J.; Copetti, Dario; Búrquez, Alberto; Bustamante, Enriquena; Charboneau, Joseph L. M.; Eguiarte, Luis E.; Kumar, Sudhir; Lee, Hyun Oh; Lee, Junki (2015-07-01). "Exceptional reduction of the plastid genome of saguaro cactus (Carnegiea gigantea): Loss of the ndh gene suite and inverted repeat". American Journal of Botany. 102 (7): 1115–1127. doi:10.3732/ajb.1500184. ISSN   0002-9122. PMID   26199368.
  13. 1 2 "Where Saguaros Grow - Saguaro National Park (U.S. National Park Service)". www.nps.gov. Retrieved 24 April 2018.
  14. Mark Elbroch; Eleanor Marie Marks; C. Diane Boretos (2001). Bird tracks and sign. Stackpole Books. p. 311. ISBN   0-8117-2696-7. Cavities in saguaro cactuses in the Southwest are common. Both gilded flickers and Gila woodpeckers make these cavities for nesting, but they often choose different locations on the cactus. The stouter bills of the gilded flickers allow them to cut cavities through the wooden ribs near the top of the cactus where the ribs converge. Gila woodpeckers stay at midlevel on the cactus where the ribs are separated enough to cut a cavity between them. Cavities in saguaros are cut out by these birds the year before they are inhabited. The excavated cactus secretes a fluid that hardens into a scab, thus preventing water loss, which could kill the cactus, as well as waterproofing the inside of the next cavity.
  15. "Gila woodpecker". Nature Conservancy. Retrieved 2011-01-24. Although they do not use them immediately, waiting first for the sap to harden, Gila woodpeckers excavate cavities in cacti and trees as nesting sites. Females typically lay two broods a year of three to five eggs, which incubate for 14 days. Once abandoned, the cavities are occupied by reptiles, rodents, and small birds like kestrels, elf owls, flycatchers, and wrens. In the desert, the woodpeckers perform the important ecological function of removing unhealthy flesh from the saguaro cactus. Some insects on which it feeds carry diseases, harmless to the bird, which damage the cactus and leave discolorations. The marks signal larvae to the bird, and as it excavates the insects, it also cuts away the diseased tissue. As the sap hardens, the cactus is healed, and the excavation becomes a convenient nesting site.
  16. 1 2 Klingaman, Gerald (December 12, 2008), Plant of the Week: Saguaro Cactus, University of Arkansas, archived from the original on April 5, 2013, retrieved 2013-02-13.
  17. "Article 11: Arizona Native Plants". Arizona Department of Agriculture. Archived from the original on September 20, 2013.
  18. "<unknown>" (PDF). Arizona Department of Agriculture. Archived from the original (PDF) on September 20, 2013.
  19. "Arizona Revised Statutes, A.R.S. 3-904.(H): Destruction of protected plants by private landowners; notice; exception". Arizona State Legislature.
  20. 1 2 Mikkelson, David (February 8, 2015), Death by Saguaro, Snopes, retrieved 2017-01-20
  21. Trimble, Marshall (2012). "Only On Hold Strange Laws Still On The Books In Arizona". Tucson News Now. Hold. Retrieved July 2, 2017.
  22. Snyder, Stephanie (2010). "Safety of native plants protected under Arizona law". ASU.edu. Chevas Samuels, McKenzie Manning, Stephanie Snyder. Retrieved July 2, 2017. “While damaging a cactus in Arizona will not warrant the rumored possibility of 25 years in prison, it is still considered a class four felony.”
  23. Inc., General Mills. "Cooking Ideas from Old El Paso". www.oldelpaso.com. Retrieved 24 April 2018.
  24. Yep Roc Records (11 March 2015). "Reverend Horton Heat - "Ain't No Saguaro in Texas" (Official Audio)" . Retrieved 24 April 2018 via YouTube.

Bibliography