Cacti of the Mojave Desert - Earth and Planetary Remote Sensing

Dicotyledon- Two leaf embryo
Single celled fruit
Areoles- Place of all growthside branches, flowers, spines
• Desert and Rainforest
• Native to North America,
South America, and the West
– Must have developed in the New
World after continental drift
– Warm weather and low rainfall
– No known fossils
• Crassulacean Acid Metabolism
• Stomata- pores- gas and water vapor
– In desert- must remain closed all day to
conserve water
– Take in Carbon Dioxide at night
• Without sunlight- can’t make sugar- make
malic acid instead
– Produces sugar through Calvin Cycle
• Protection from animals
• Water Collection- dew, downward facingdirect rainwater
• Reflect light away
• Grow out of areoles
• Radial and central
• Fully hydrated Stem- almost 100% water
• Ribs and Tubercles- help stem expand and
• 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)
• 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, crystalsprotection from animals
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
• Cylinder shaped body
• 1-4 feet tall, live 20-30 years
• Parallel ridges (accordian)- expand or
contract with amount of water it’s holding
• 3-4 inch spines
• Yellow, 2 in. diameter flowers in ring
around top in late spring and early
Uses of the Barrel Cactus
• Stewed by Native Americans- cabbage-like
• Drank water from pulp
• Used spines to make fish hooks
• 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
• glochids- barbed bristles organized in
Uses of the Beavertail Cactus
• Fruit is very sweet
• When pads of cactus are
young, can be cooked and
used as greens
• 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
Uses of Cottontop Cactus
• Panamint tribe ate
the seeds of the
• Pulp of the stem
contains watery
• Thorns used for
basket making
• 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
• Found in creosote bush scrub- widely
spaced shrubs on low lying expanses
MORE Foxtail Cactus!
• Columnar
• About one foot tall
• Bright pink flowers from February to Aprilclose 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
– Long and stout
• 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
MORE Mojave Mound
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
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 medicinetreat diabetes, ulcers,
inflammation- but more
clinical support
• Planted on steep slopes to
control erosion
• 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!!!
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
• 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
MORE Silver Cholla
• 3-4 feet tall
• Cylindrical segmentseasily 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
Uses for the Teddy Bear Cholla
• Animals in the desert (such as rats) use
fallen joints for protecting and
camouflaging nests
Works Consulted