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Red Rock Canyon NCA
Plant Communities
The land surface of the Red Rock Canyon NCA supports a wide variety of plant species. This variety is
due to soil types and depth, elevation, exposure, temperature, precipitation, and existing and past use.
An area that supports vegetation and has one or more dominant or co-dominant species is identified
as a vegetation type, usually named after the dominant or most abundant species. Vegetation types
vary greatly in the number of species and in the percentage of each species in the total composition. The
vegetation in the area can be divided into nine major vegetation types:
pinyon-juniper;
joshua tree;
rabbit brush;
oak brush;
blackbrush;
manzanita;
desert shrub;
barren and
unique vegetation
The following discussion describes each of these major vegetation types (BLM Range Inventory, 1979).
PINYON-JUNIPER
This type lies between 5,000 and 7,000 feet and receives between 10 to 18 inches of precipitation a year. It forms
a belt between the desert below and the true forest above. Precipitation is the first and soil shallowness the
second limiting factor. The lower edge of the belt is occupied by juniper; but, at higher elevations pinyon pine
and juniper intermix. At the upper edge of the belt, pinyon pine becomes prevalent curl-leaf mountain mahogany, big
sagebrush and blackbrush are also found in this type in varying amounts. Three awn, Nevada bluegrass and cheatgrass
make up the majority of the grass species present.
JOSHUA TREE
This type is found between 3,600 and 4,200 feet and receives between 8 and 10 inches of precipitation annually. Soils
are moderately deep to deep. Joshua tree is the dominant species in this type and makes up 3 to 10 percent of the
total species composition. Blackbrush, creosote bush, Mormon Tea and burrobrush also make up portions of this
type. Grasses are usually sparse and species are mostly annuals.
RABBITBRUSH
This type can range between 3,400 and 9,000 feet elevation, but in this area it is found between 3,400 and 4,200
feet. Annual precipitation usually is low, ranging from six to eight inches. Rabbitbrush is generally found on
eroded or disturbed soils along roadsides and in wash bottoms. It characterizes a soil with a relatively low
alkali content.
OAK BRUSH
This type generally occurs from 4,000 to 6,000 feet in Red Rock Canyon NCA. Soils are moderately deep to
deep. Precipitation is usually between eight and 10 inches. Sagebrush, manzanita, snowberry and rabbitbrush are
some of the scrub species that also occur in this type in varying amounts. Nevada bluegrass, Indian rice grass
and big galleta, as well as several annual grasses and forbs also occur in this type. Soil difference and soil
moisture, as affected by slope and aspect (e.g.., north slope vs. south slope), probably account for the occurrence
of oak brush .
BLACKBRUSH
The blackbrush type is usually found from 4,000 to 6,000 feet elevation. Topography is usually steep to rolling
and soils are very shallow to shallow, or two to 20 inches. This type is usually found in association with
creosote, hopsage, sagebrush and wolfberry. Precipitation is fairly low, five to eight inches per year.
MANZANITA
This type is found in the area surrounding the escarpment in the rocky canyons and on the walls. Vegetation is
found only on areas where soil has accumulated. The most limiting factor in this area is availability of
soil. Precipitation usually ranges from eight to ten inches annually. Manzanita is the most dominant plant. Other
species in this type present in varying amounts are: turbinella oak, cliffrose, desert barberry, desert ceanothus,
snowberry, apache plume, juniper and pinyon pine. Various annual grasses and forbs also occur.
DESERT SHRUB
Cat-claw Cactus
The desert shrub type is found generally to the east of the sandstone escarpment. Precipitation ranges from 5 to
8 inches annually. Soils are generally shallow to very shallow. Species found in this community consist of
Spanish bayonet, blackbrush, Mormon tea, Cheesebush, Spiny Menodora, Desert Almond, Sagebrush, Bursage,
cholla cactus, dalea, turpentine bush and catclaw. Grasses commonly found include needle grass, sand dropseed and
big galleta grass.
In the desert shrub type, moist years produce an exceptional growth of annual plants. The wide variety of small
flowering plants include buckwheats, marigolds, mallows and desert poppy. Several species of grasses also occur
in moist years.
BARREN
This type is found on the eastern edge of the area and is mostly bare rock. Vegetative cover is found only in
areas where soils accumulate and where water periodically stands, allowing seed germination. The main species
are pinyon pine, juniper, manzanita, sagebrush, snakeweed and creosote. Sparse perennial grasses occur along
with some annual grasses and forbs.
UNIQUE VEGETATION
This type is limited mainly to the deep, cool, well-watered canyons of the escarpment. These canyons, especially
Pine Creek, Oak Creek and First Creek, provide a microclimate which supports small communities of ponderosa pine
and several other species not commonly found at this low elevation. Some of these other species are: willow,
serviceberry, snowberry, manzanita, sagebrush, black cottonwood and Gambel's oak. Nevada bluegrass, Indian
ricegrass, blue grama and big galleta make up some of the grass species found there.
The average age of ponderosa pines in these areas is 180 years (BLM Forest Inventory, 1979). Reproduction is
marginal. The trees are mostly concentrated in and along the creek bottoms. They may represent a relic population
that was once part of a large pine forest, with these trees surviving in small pockets long after the rest of the
forest disappeared.
In the past 40 years, many unique plants in the area have been subjected to heavy collection pressure. The
sword fern, probably the most collected plant, has been reduced from large beds and glades to only occasional
plants by trampling and collection.
Other unique plants in the area include Agave (Agave utahensis nevadensis), a conspicuous part of the cliff
community in the Spring Mountains and Charleston mountain pricklypear cactus (Opuntia charlastonensis) which
occurs only in the higher elevation, wooded areas of the Spring Mountains.
Riparian vegetation is associated with springs, creeks and dry washes. Plants more typical of the riparian type
include mesquite, catclaw acacia, salt cedar and desert willow. In moister areas or along stream banks, cattails,
rushes, willows and other semi-aquatic plants can be found.
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Also See:
Desert Habitats
Pinyon-juniper Woodland
This habitat includes sagebrush, goldenbush, wildflowers such as Indian paintbrush, and Mojave prickly pear cactus. Also look for ...
--Pinyon Pine
--Juniper
Joshua tree Woodland
Though can grow 50 feet tall, they are not really trees but a species of ...
--Joshua Tree
Yucca Cactus Scrub
Cactus, or mixed desert scrub includes the popular notion of "desert." ...
--Mojave Yucca
Creosote Bush Scrub
Low-lying expanses are covered by these widely spaced shrubs. Creosote bushes are said to be some of the ...
--Creosote Bush
Desert Wash
Unlike the sparse vegetation in most of the Mojave, plantlife in washes is lush and deep-rooted. Plants range
from shrubs such as the ...
Desert Riparian
These habitats are found adjacent to permanent surface water, such as streams and springs. Usually an abrupt transition occurs between this and adjacent ...
--Mesquite
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