Cacti of the Mojave Desert

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CACTI
of the Mojave
Merrill Rudd
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Join the Cacti Club!

• Perennial
• Dicotyledon- Two leaf embryo
• Single celled fruit
• Areoles- Place of all growth- side branches,
  flowers, spines
• Desert and Rainforest
• Native to North America, South America, and the
  West Indies
• Must have developed in the New World after
  continental drift
• Warm weather and low rainfall climates
• No known fossils

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CAM Photosynthesis

• Crassulacean Acid Metabolism
• Stomata- pores- gas and water vapor exchange
• In desert- must remain closed all day to conserve
  water
• Take in Carbon Dioxide at night
• Without sunlight- cant make sugar- make malic
  acid instead
• Produces sugar through Calvin Cycle

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A Succulent Superstar!
SPINES

• Protection from animals
• Water Collection- dew, downward facing- direct
  rainwater
• Reflect light away
• Grow out of areoles
• Radial and central

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STEM

• Fully hydrated Stem- almost 100 water
• Ribs and Tubercles- help stem expand and contract
• Ribs- channel water to roots, shade stem
• photosynthesis is inefficient ? cacti grow slowly
• Globular shape- best for water storage- max
  volume, min surface area
• Water converted to mucilaginous substance- not
  evaporated as easily (lower freezing point)

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SKIN

• Skin- Epidermis and Hypodermis
• Epidermis- covered by waxy layer, holds in water
  and reflects light
• Fewer stomata per square area- close tighter than
  other plants stomata
• Hypodermis- structural support,
  crystals-protection from animals

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ROOTS

• shallow, spread laterally
• corky layer prevents water loss
• Rainfall- new roots form to soak up water
• Drought- roots shrink- air gap, prevents water
  from escaping back to soil

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A Field Guide to...
CACTI
of the Mojave
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Barrel Cactus

• Cylinder shaped body
• 1-4 feet tall, live 20-30 years
• Parallel ridges (accordian)- expand or contract
  with amount of water its holding
• 3-4 inch spines
• Yellow, 2 in. diameter flowers in ring around top
  in late spring and early summer

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Uses of the Barrel Cactus

• Stewed by Native Americans- cabbage-like
• Drank water from pulp
• Used spines to make fish hooks

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Beavertail Cactus

• Flat, pad shaped, heart shaped
• Green to purple color
• 2 feet tall, 4 feet wide

• 2-3 inch wide magenta flowers clustered at top
  of pads, between March and April
• Grow on rocky slopes, below 6,000 feet elevation
• glochids- barbed bristles organized in clusters

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Uses of the Beavertail Cactus

• Fruit is very sweet
• When pads of cactus are young, can be cooked and
  used as greens

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Cottontop Cactus

• About 1 foot tall
• Clusters of 10 to 30 stems
• Spherical to cylindrical, short stems
• ribbed, with long spines
• Grow on rocky slopes between elevations of 1,000
  and 5,000 feet.
• Cotton-like fiber grows on fruit and base of
  flower (yellow flower streaked with pink, blooms
  in late spring)
• Cotton stays on cactus after fruit and flower are
  gone

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Uses of Cottontop Cactus

• Panamint tribe ate the seeds of the fruit
• Pulp of the stem contains watery juice
• Thorns used for basket making

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Foxtail Cactus

• One stem, 2-3 inches diameter, 6-8 inches tall
• Pink or magenta flowers in May and June

• Sandy or rocky areas
• Single stems clump together to form colonies
• Found in creosote bush scrub- widely spaced
  shrubs on low lying expanses

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MORE Foxtail Cactus!
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Hedgehog Cactus

• Columnar
• About one foot tall
• Bright pink flowers from February to April- close
  at night and open in the morning
• Grow from side of stem
• Fruit is edible- about one inch long
• 4-6 yellow or brown central spines (2-3 inches
  long) and about 10 smaller radial spines
• Long and stout

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MORE Hedgehog Cactus
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Mojave Mound Cactus aka Claret Cup Cactus

• 1-500 single spherical or oblong stems grow in
  clusters
• Stems 1 foot tall
• 8-12 spines per areole
• Red spines on top of stems
• Areoles about a half inch apart
• May be curving and flexible

• Scarlet flowers- diurnal (open for 2-3 days)
• Red, juicy fruit

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MORE Mojave Mound
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Old Man Prickly Pear Cactus

• Up to 3 feet tall
• Elliptical, oblong shape
• Green, brownish purple color
• Two or three pads jointed together
• Yellow flowers, two inches wide, in May and June
• May become pink or orange as they age
• Fruits (tunas) edible, covered in spines

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Uses of the Prickly Pear

• Juice, jelly, candy, tea, and alcoholic drinks
• Native Americans- used to treat burns
• Used as tea to help mothers during childbirth
• Mexican folk medicine- treat diabetes, ulcers,
  inflammation- but more clinical support
• Planted on steep slopes to control erosion

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Pencil Cholla

• Up to 5 feet tall
• Cylindrical stems, smooth, with diamond pattern

• One central spine per areole
• 2 inches long, straight, round
• Small single flower at the end of stem segment
• Yellow, Orange, or Red
• Grow on sandy, rocky, or gravelly soil
• up to 4,000 feet elevation
• Low growing and hidden in shrubs Watch out!!!

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Uses for Pencil Cholla

• Fruit and pad- can be eaten raw, cooked, or dried
  for later use
• Seeds- roasted and ground up, used as thickener
• Can be used to make gum
• Mixed with oil to make candle
• Added to plaster to make it stickier

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Silver Cholla

• 2-5 feet tall
• Made up of short cylindrical segments
• Branches densely covered by spines- about one
  inch long, covered by paper-like sheath
• 9-20 spines per areole
• Greenish-yellow flowers bloom May-June
• Sandy, rocky soils
• Moderate slopes
• Elevation 1,000 to 5,000 feet

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MORE Silver Cholla
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Teddy Bear Cholla

• 3-4 feet tall
• Cylindrical segments- easily detached
• Detached segments root and grow

• Densely covered by yellowish spines
• Looks soft from a distance
• Cooling mechanism- protects stems from intense
  sunlight
• Yellow-green flowers at top of stems in spring
• Rocky, south facing slopes
• Below elevation of 3,000 feet

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Uses for the Teddy Bear Cholla

• Animals in the desert (such as rats) use fallen
  joints for protecting and camouflaging nests

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IDENTIFUS
that
CACTUS!
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Beavertail Cactus
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Hedgehog Cactus
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Cottontop Cactus
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Pencil Cholla
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Old Man Prickly Pear
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Teddy Bear Cholla
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Foxtail Cactus
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Mojave Mound Cactus
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Barrel Cactus
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Silver Cholla
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Works Consulted

• http//mojavedesert.net/plants/mojave-desert-cactu
  s.html
• http//www.desertusa.com/mag98/may/stories/cactus.
  html
• http//www.blueplanetbiomes.org/barrel_cactus.htm
• http//earthnotes.tripod.com/cactus.htm
• http//www.fourdir.com/great_basin_forager_culture
  .htm
• http//calflora.net/bloomingplants/mojavemoundcact
  us.html
• http//www.drugs.com/npp/prickly-pear.html
• http//www.ibiblio.org/pfaf/cgi-bin/arr_html?Opunt
  iaramosissima
• http//www.cactusmuseum.com/survival.asp