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Ecological site R030XB056NV

SHALLOW GRANITIC SLOPE 5-7 P.Z.

Last updated: 2/24/2025
Accessed: 08/29/2026

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General information

Provisional. A provisional ecological site description has undergone quality control and quality assurance review. It contains a working state and transition model and enough information to identify the ecological site.

MLRA notes

Major Land Resource Area (MLRA): 030X–Mojave Basin and Range

The Mojave Desert Major Land Resource Area (MLRA 30) is found in southern California, southern Nevada, the extreme southwest corner of Utah and northwestern Arizona within the Basin and Range Province of the Intermontane Plateaus. The Mojave Desert is a transitional area between hot deserts and cold deserts where close proximity of these desert types exert enough influence on each other to distinguish these desert types from the hot and cold deserts beyond the Mojave. Kottek et. al 2006 defines hot deserts as areas where mean annual air temperatures are above 64 F (18 C) and cold deserts as areas where mean annual air temperatures are below 64 F (18 C). Steep elevation gradients within the Mojave create islands of low elevation hot desert areas surrounded by islands of high elevation cold desert areas.

The Mojave Desert receives less than 10 inches of mean annual precipitation. Mojave Desert low elevation areas are often hyper-arid while high elevation cold deserts are often semi-arid with the majority of the Mojave being an arid climate. Hyper-arid areas receive less than 4 inches of mean annual precipitation and semi-arid areas receive more than 8 inches of precipitation (Salem 1989). The western Mojave receives very little precipitation during the summer months while the eastern Mojave experiences some summer monsoonal activity.

In summary, the Mojave is a land of extremes. Elevation gradients contribute to extremely hot and dry summers and cold moist winters where temperature highs and lows can fluctuate greatly between day and night, from day to day and from winter to summer. Precipitation falls more consistently at higher elevations while lower elevations can experience long intervals without any precipitation. Lower elevations also experience a low frequency of precipitation events so that the majority of annual precipitation may come in only a couple precipitation events during the whole year. Hot desert areas influence cold desert areas by increasing the extreme highs and shortening the length of below freezing events. Cold desert areas influence hot desert areas by increasing the extreme lows and increasing the length of below freezing events. Average precipitation and temperature values contribute little understanding to the extremes which govern wildland plant communities across the Mojave.

Arid Eastern Mojave Land Resource Unit (XB)

LRU notes

The Mojave Desert is currently divided into 4 Land Resource Units (LRUs). This ecological site is within the Arid Eastern Mojave LRU where precipitation is bi-modal, occurring during the winter months and summer months. The Arid Eastern Mojave LRU is designated by the 'XB' symbol within the ecological site ID. This LRU is found across the eastern half of California, much of the mid-elevations of Nevada, the southernmost portions of western Utah, and the mid-elevations of northwestern Arizona. This LRU is essentially equivalent to the Eastern Mojave Basins and Eastern Mojave Low Ranges and Arid Footslopes of EPA Level IV Ecoregions

Elevations range from 1650 to 4000 feet and precipitation is between 4 to 8 inches per year. This LRU is distinguished from the Arid Western Mojave (XA) by the summer precipitation, falling between July and September, which tends to support more warm season plant species. The 'XB' LRU is generally east of the Mojave River and the 117 W meridian (Hereford et. al 2004). Vegetation includes creosote bush, burrobush, Nevada jointfir, ratany, Mojave yucca, Joshua tree, cacti, big galleta grass and several other warm season grasses. At the upper portions of the LRU, plant production and diversity are greater and blackbrush is a common dominant shrub.

Ecological site concept

This ecological site occurs on northerly mountain and hill slopes between 3000 and 3800 feet elevation. Soils are formed in colluvium and residuum from plutonic or plutonic metamorphosed material. Surface fragments over 3 inches diameter cover less than 15 percent of the soil surface.

This is a group concept and provisional STM that also covers the following ecological sites: R030XB001NV, R030XB008NV, R030XF033CA. R030XB016NV, R030XB144CA

Associated sites

R030XB057NV	SHALLOW GRANITIC LOAM 5-7 P.Z.

R030XB057NV

SHALLOW GRANITIC LOAM 5-7 P.Z.

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Table 1. Dominant plant species

Tree	Not specified
Shrub	(1) Coleogyne ramosissima
Herbaceous	(1) Achnatherum speciosum

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Physiographic features

This site occurs on hills, mountains, and upper fan remnants on all exposures. Slopes range from 2 to over 75 percent, but slope gradients of 8 to 30 percent are typical. Elevations are 2200 to 7000 feet.

Table 2. Representative physiographic features

Landforms	(1) Fan remnant (2) Hill (3) Mountain
Elevation	2200 – 7000 ft
Slope	2 – 75 %
Aspect	Aspect is not a significant factor

Climatic features

The climate is hot and arid, with mild winters and very hot summers. Precipitation is greatest in the winter with a lesser secondary peak in summer, typical of the Mojave Desert. Average annual precipitation is 5 to 7 inches. Mean annual air temperature is 57 to 67 degrees F. The average growing season is about 170 to 270 days.

Table 3 Representative climatic features

Frost-free period (average)	270 days
Freeze-free period (average)
Precipitation total (average)	10 in

Bar

Line

Figure 1. Monthly precipitation range

Bar

Line

Figure 2. Monthly average minimum and maximum temperature

Soil features

The soils associated with this site are typically shallow to very shallow to bedrock or a duripan, and derived from volcanic parent materials. Surface soil texture varies from cobbly, stony, or gravelly sandy loams to loams. Water intake rates are moderately slow to moderately rapid, available water capacity is very low, runoff is low to very high and the soils are well to somewhat excessively drained. The soil series associated with this site include: Commski, Meadview, Nolena, and Singatse.

Table 4. Representative soil features

Parent material	(1) Colluvium – volcanic breccia
Surface texture	(1) Extremely gravelly loam (2) Very gravelly sandy loam (3) Very gravelly sandy clay loam
Family particle size	(1) Loamy
Drainage class	Well drained to somewhat excessively drained
Permeability class	Moderately slow to moderately rapid
Soil depth	4 – 84 in
Surface fragment cover <=3"	40 – 85 %
Surface fragment cover >3"	2 – 30 %
Available water capacity (0-40in)	0.2 – 2.6 in
Calcium carbonate equivalent (0-40in)	0 – 70 %
Electrical conductivity (0-40in)	0 – 4 mmhos/cm
Sodium adsorption ratio (0-40in)	0 – 12
Soil reaction (1:1 water) (0-40in)	7.4 – 9
Subsurface fragment volume <=3" (Depth not specified)	26 – 72 %
Subsurface fragment volume >3" (Depth not specified)	0 – 35 %

Ecological dynamics

Blackbrush is a long-lived and generally considered a climax species. It is a non-sprouter; regeneration depends on wind pollinated seed and heavy winter precipitation, and is therefore slow to re-colonize burned areas (Anderson 2001). Blackbrush recruitment is episodic, like many shrubs in arid systems, when conditions are favorable large seed crops are produced and the rest of the time is characterized by minimal seed output (Pendleton and Meyer 2004). Blackbrush seeds are frequently cached away by rodents, until conditions are conducive for germination. Typically, germination occurs during the winter and early spring, given the proper moisture conditions and cool soil temperatures (Pendleton 2008). Seeds require cold stratification before germination and the survival of seedlings following germination is dependent on the availability of spring time moisture (Pendleton 2008).

Fire Ecology:
Historic fire return intervals for blackbrush communities were typically 35 to 100 years. Blackbrush stands are subject to fire, and fire will start and spread easily due to the high density and resinous foliage. In many areas, frequent large fires have eliminated blackbrush stands. These communities will burn under conditions of high temperature, high wind velocity and low relative humidity. Fire also occurs in stands with a proportion of herbaceous annuals and perennials. Fire frequency increases if sites are invaded with red brome or cheatgrass. Blackbrush is a nonsprouter and is removed by fire. Current knowledge indicates that the return of blackbrush may take years. Succeeding communities after fire are variable and burn areas are usually dominated by annual species the first few years following fire.

Plant succession varies wildly following fire and blackbrush communities can be replaced by undesirable species, like redstem filaree, snakeweed (Gutierrezia spp), and Bromus spp. (Anderson 2001). The response of woody vegetation post-fire largely depends on site history, species present prior to the fire, as well as, fire severity and frequency. Common plant species include those that are known to sprout, be fire resistant, or are prolific seed producers. Mojave buckwheat, creosotebush, Ephedra spp., Encelia spp., and white bursage are all found on burned blackbrush sites. However, it is uncommon to see blackbrush recruitment under the current climatic conditions, especially at the lower extent of its elevational range. The traits that allow established blackbrush communities to persist for centuries, even after environmental conditions have changed are now precluding seedling establishment under the current climatic regime (Pendleton and Meyer 2004).

Under current environmental conditions in the Mojave Desert it is common to see disturbed blackbrush sites dominated by the semi-erect, evergreen, Mojave buckwheat. Eriogonum species are frequently pioneering species following natural disturbance (Meyer 2008). Following severe fires resprout success of Mojave buckwheat is limited. Most regeneration is from seeds (Montalvo 2010). The seedbank of Mojave buckwheat will not persist under a frequent fire regime. Under an unnaturally high fire frequency herbaceous communities are favored over woody dominated plant communities, which cause habitat degradation.

Desert needlegrass has persistent dead leaf bases, which make it susceptible to burning. Fiore removes the accumulation; a rapid, cool fire will not burn deep into the root crown and surviving tufts will resprout. Fire top-kills bush muhly. A nonrhizomatous species, bush muhly regenerates following fire from soil-stored seed. Burning causes at least short-term decline of bush muhly. Recovery time is thought to vary considerably and is probably dependent on postfire weather and competition. When ungrazed, bush muhly's dense growth may contribute to fire spread. It may be most susceptible to fire damage when growing beneath shrubs because of increased fuels and higher temperatures as shrubs burn.

State and transition model

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Standard diagram

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State 1
Reference State

This state represents the natural range of variability under pristine conditions. The reference state is dominated by long-lived evergreen shrub communities with an understory of cool and warm season perennial bunchgrasses. Plant community phase changes are primarily driven by fire, long-term drought and insect attack. Historically, fire is rare in this system, but does impact long-term plant community dynamics.

Community 1.1
Reference Plant Community

The reference plant community is dominated by blackbrush. Annuals are abundant in wet years.
Potential vegetative composition is about 15% grasses, 10% annual and perennial forbs and 75% shrubs. Approximate ground cover (basal and crown) is 10 to 15 percent.

Figure 3. Annual production by plant type (representative values) or group (midpoint values)

Table 5. Annual production by plant type

Plant type	Low (lb/acre)	Representative value (lb/acre)	High (lb/acre)
Shrub/Vine	56	150	225
Grass/Grasslike	12	30	45
Forb	7	20	30
Total	75	200	300

State 2
Invaded

Introduced annuals such as red brome, schismus and redstem stork's bill have invaded the reference plant community and have become a dominant component of the herbaceous cover. This invasion of non-natives is attributed to a combination of factors including: 1) surface disturbances, 2) changes in the kinds of animals and their grazing patterns, 3) drought, and 4) changes in fire history. These non-natives annuals are highly flammable and promote wildfires where fires historically have been infrequent.
CORA would persist after this invasion by non-native annuals, but the other shrubs and desirable grasses would either be unsuccessful in competing with the non-natives or removed from the system.
A biotic threshold has been crossed, with the introduction of non-natives that cannot be removed from the system. The presence of non-natives has reduced the ecological resilience of the site. Following a disturbance this state relies on the availability of an offsite seed source. These non-natives have the potential to significantly alter disturbance regimes from their historic range.

Community 2.1
Plant Community Phase 2.1

This plant community is compositionally similar to the Reference Plant Community with the presence of non-native species in the understory. Primary ecological processes have not been compromised at this time.

Community 2.2
Plant Community Phase 2.2

This plant community is characterized by increased annual, perennial, native and non-native grasses. Few surviving shrubs will remain on the site. This plant community is identified as “at-risk”. Continued heavy disturbance or repeated fire will exclude native vegetation and change the ecological dynamics of the site.

Community 2.3
Plant Community Phase 2.3

Shrubs have begun to regenerate. Woody species with high seed production and early establishment will be the first to return. Once large shrubs are established and begin to produce shade it will favor the establishment of additional native perennials.

Pathway 2.1a
Community 2.1 to 2.2

Anthropogenic disturbance removes shrubs and favors an increase of herbaceous vegetation and non-native species.

Pathway 2.2a
Community 2.2 to 2.3

Changes in management remove disturbance and allow woody species to regenerate. Post disturbance colonization by woody species will be limited to thoes with high growth rates, high reproductive ability and relatively short life spans (GUTIE, ENFAV, ERFA). Blackbrush will begin to reestablish provided favorable climatic conditions and available seed source.

Pathway 2.3a
Community 2.3 to 2.1

Many years with NO fire, minimal disturbance, the presence of a blackbrush seed source, ideal climatic conditions and multiple recruitment pulses blackbrush seedlings will establish and recruit into the stand.

State 3
Burned With No Blackbrush

This state is characterized by the inability of blackbrush to return to the site. An abiotic and/or biotic threshold has been crossed, due to insufficient climatic conditions and/or lack of an available seed source, respectively. In the absence of ideal conditions blackbrush will not return to the site. Shrubs with high growth rates and high reproductive capacities will persist after invasion by non-native annuals. However, other shrubs, such as blackbrush, are unsuccessful competitors in the disturbance regime created by the non-natives and can be removed from the system.

Community 3.1
Plant Community Phase 3.1

Is characterized by dominance of grasses; annual, perennial, native and non-native. Few surviving shrubs remain on the site. Non-native annuals provide a significant amount of herbaceous biomass.

Community 3.2
Plant Community Phase 3.2

This plant community is dominated by pioneering woody species tolerant of post fire conditions. Scattered shrubs consist of those with the ability to sprout from the root crown following fire. Perennial bunchgrasses and non-native annuals are common and wide spread.

Community 3.3
Plant Community Phase 3.3

This plant community is dominated by a variety of shrubs that were present in smaller quantities in the Reference State. Blackbrush continues to be excluded from this site due to the lack of seed source and ideal conditions required for recruitment and establishment.

Figure 4. Annual production by plant type (representative values) or group (midpoint values)

Table 6. Annual production by plant type

Plant type	Low (lb/acre)	Representative value (lb/acre)	High (lb/acre)
Shrub/Vine	60	120	180
Grass/Grasslike	30	60	90
Forb	10	20	30
Total	100	200	300

Pathway 3.1a
Community 3.1 to 3.2

Time without disturbance pioneering shrubs germinate and establish from an offsite seed source and sprouting shrubs begin to reappear.

Pathway 3.2a
Community 3.2 to 3.1

Small scale fire of other localized disturbances remove patches of woody vegetation and encourage growth of perennial bunchgrasses and non-native annuals.

Pathway 3.2b
Community 3.2 to 3.3

Removal of disturbance and the absence of fire favors establishment of long-live native perennial vegetation.

Pathway 3.3a
Community 3.3 to 3.1

Large disturbance, like fire, removes woody vegetation and promotes growth of non-native annuals.

Transition 1
State 1 to 2

Introduction of non-natives due to anthropogenic disturbances, including OHV use, dry land farming, grazing, linear corridors, mining, military training operations, and settlements.

Transition 2a
State 2 to 3

Large scale high intensity fire in combination with insufficient climatic conditions for germination and establishment of blackbrush.

Additional community tables

Table 7. Community 1.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)
Grass/Grasslike
1	Primary Perennial Grasses			12–40
	desert needlegrass	ACSP12	Achnatherum speciosum	10–30	–
	bush muhly	MUPO2	Muhlenbergia porteri	2–10	–
2	Secondary Perennial Grasses			1–10
	Indian ricegrass	ACHY	Achnatherum hymenoides	1–4	–
	threeawn	ARIST	Aristida	1–4	–
	big galleta	PLRI3	Pleuraphis rigida	1–4	–
3	Annual Grasses			1–10
Forb
4	Perennial forbs			4–16
	desert globemallow	SPAM2	Sphaeralcea ambigua	1–4	–
5	Annual forbs			1–16
Shrub/Vine
6	Primary shrubs			120–140
	blackbrush	CORA	Coleogyne ramosissima	120–140	–
7	Secondary shrubs			10–50
	burrobush	AMDU2	Ambrosia dumosa	2–6	–
	jointfir	EPHED	Ephedra	2–6	–
	Eastern Mojave buckwheat	ERFAP	Eriogonum fasciculatum var. polifolium	2–6	–
	goldenbush	ERICA2	Ericameria	2–6	–
	snakeweed	GUTIE	Gutierrezia	2–6	–
	creosote bush	LATR2	Larrea tridentata	2–6	–
	water jacket	LYAN	Lycium andersonii	2–6	–
	spiny menodora	MESP2	Menodora spinescens	2–6	–

Table 8. Community 2.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 9. Community 2.2 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 10. Community 2.3 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 11. Community 3.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 12. Community 3.2 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 13. Community 3.3 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)
Grass/Grasslike
1	Primary Perennial Grasses			44–90
	desert needlegrass	ACSP12	Achnatherum speciosum	30–50	–
	bush muhly	MUPO2	Muhlenbergia porteri	10–30	–
	big galleta	PLRI3	Pleuraphis rigida	4–10	–
2	Secondary Perennial Grasses			1–10
	threeawn	ARIST	Aristida	1–4	–
	Indian ricegrass	ACHY	Achnatherum hymenoides	1–4	–
3	Annual Grasses			1–10
Forb
4	Perennial Forbs			4–16
	desert marigold	BAILE	Baileya	1–4	–
	desert globemallow	SPAM2	Sphaeralcea ambigua	1–4	–
5	Annual Forbs			1–16
Shrub/Vine
6	Primary Shrubs			102–182
	Eastern Mojave buckwheat	ERFAP	Eriogonum fasciculatum var. polifolium	80–110	–
	burrobush	AMDU2	Ambrosia dumosa	10–20	–
	jointfir	EPHED	Ephedra	4–20	–
7	Secondary Shrubs			10–30
	catclaw acacia	ACGR	Acacia greggii	2–6	–
	brittlebush	ENFA	Encelia farinosa	2–6	–
	burrobrush	HYSA	Hymenoclea salsola	2–6	–
	creosote bush	LATR2	Larrea tridentata	2–6	–
	desert-thorn	LYCIU	Lycium	2–6	–
	pricklypear	OPUNT	Opuntia	2–6	–
	Fremont's dalea	PSFR	Psorothamnus fremontii	2–6	–
	Mojave yucca	YUSC2	Yucca schidigera	2–6	–

Interpretations

Animal community

Livestock Interpretations:
This site has limited value for livestock grazing, due to the low forage production and steep slopes. Grazing management should be keyed to perennial grass or palatable shrub production. Blackbrush is not preferred as forage by domestic livestock, but does provide some forage during the spring, summer and fall. Young desert needlegrass is palatable to all classes of livestock. Mature herbage is moderately grazed by horses and cattle, but rarely grazed by sheep. Bush muhly is readily eaten by livestock throughout the year when available; however, it is usually not abundant enough to provide much forage. It is grazed heavily in winter when other species become scarce. Because of its branching habit, it is extremely susceptible to heavy grazing. Bush muhly is damaged when continuously grazed to a stubble height of less than 4 inches (10 cm).
Stocking rates vary over time depending upon season of use, climate variations, site, and previous and current management goals. A safe starting stocking rate is an estimated stocking rate that is fine tuned by the client by adaptive management through the year and from year to year.

Wildlife Interpretations:
Blackbrush is a valuable browse species for bighorn sheep. It may also comprise up to 25% of the mule deer winter diet. Blackbrush provides cover for upland game birds, nongame birds and small mammals. Young desert needlegrass is palatable to many species of wildlife. Desert needlegrass produces considerable basal foliage and is good forage while young. Desert bighorn sheep graze desert needlegrass. The palatability of bush muhly for wildlife species is rated fair to poor.

Hydrological functions

Runoff is low to very high. Permeability is moderately slow to moderately rapid.

Recreational uses

Aesthetic value is derived from the diverse floral and faunal composition and the colorful flowering of wild flowers and shrubs during the spring and early summer. This site offers rewarding opportunities to photographers and for nature study. This site is used for hiking and has potential for upland and big game hunting.

Other information

Blackbrush contributes to desert fertility by 1) protecting the soil against wind erosion through retarding the movement of soil and increasing the accumulation of fine soil particles around its base; 2) protecting understory vegetation from the effects of high temperatures, thereby helping to retain surface nitrogen and adding organic matter to the soil; and 3) serving as a nitrogen reservoir through the storage of nitrogen in roots, leaves, and stems.

Supporting information

Type locality

Location 1: Clark County, NV
Township/Range/Section	T27S R64E S32
General legal description	South end of Eldorado Mountains, about 6 miles northeast of Searchlight, Clark County, Nevada.

Other references

Fire Effects Information System (Online; http://www.fs.fed.us/database/feis/plants/).

Hereford, R., R.H. Webb and C. I. Longpre. 2004. Precipitation history of the Mojave Desert region, 1893-2001 (No. 117-03).

Kottek, M., Grieser, J., Beck, C., Rudolf, B., & Rubel, F. (2006). World map of the Köppen-Geiger climate classification updated. Meteorologische Zeitschrift, 15(3), 259-263.

Pendleton, B.K. 2008. Coleogyne ramosissima Torr. Available: http://www.nsl.fs.fed.us/wpsm/index.html [2010, August 11].

Pendleton, B.K. and S.E. Meyer. 2004. Habitat-correlated variation in blackbrush (Coleogyne ramosissima: Rosaceae) seed germination response. J. of Arid Environments. 59: 229-243.

Salem, B. B. (1989). Arid zone forestry: a guide for field technicians (No. 20). Food and Agriculture Organization (FAO).

USDA-NRCS Plants Database (Online; http://www.plants.usda.gov).

Contributors

BLS/GKB
Dustin Detweiler

Approval

Sarah Quistberg, 2/24/2025

Rangeland health reference sheet

Interpreting Indicators of Rangeland Health is a qualitative assessment protocol used to determine ecosystem condition based on benchmark characteristics described in the Reference Sheet. A suite of 17 (or more) indicators are typically considered in an assessment. The ecological site(s) representative of an assessment location must be known prior to applying the protocol and must be verified based on soils and climate. Current plant community cannot be used to identify the ecological site.

Author(s)/participant(s)	P NOVAK-ECHENIQUE
Contact for lead author	State Rangeland Management Specialist
Date	04/08/2010
Approved by
Approval date
Composition (Indicators 10 and 12) based on	Annual Production

Indicators

Number and extent of rills:
Rills are rare. A few rills can be expected on steeper slopes in areas recently subjected to summer convection storms. Rock fragments armor the surface.
Presence of water flow patterns:
Water flow patterns are rare but can be expected in areas recently subjected to summer convection storms, usually on steeper slopes.
Number and height of erosional pedestals or terracettes:
Pedestals are none to rare. Occurrence is usually limited to areas of water flow patterns.
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
Bare Ground 15-25%; surface cover of rock fragments more than 85%; shrub canopy to 15%; foliar cover of perennial herbaceous plants ± 5%.
Number of gullies and erosion associated with gullies:
Gullies are none to rare.
Extent of wind scoured, blowouts and/or depositional areas:
None
Amount of litter movement (describe size and distance expected to travel):
Fine litter (foliage from grasses and annual & perennial forbs) expected to move distance of slope length during intense summer convection storms or rapid snowmelt events. Persistent litter (large woody material) will remain in place except during catastrophic events.
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Soil stability values should be 3 to 6 on most soil textures found on this site. (To be field tested.)
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
Surface structure is typically moderately thin to weak medium platy or moderate medium subangular blocky structure. Soil surface colors are brown and soils are typified by an ochric epipedon. Organic matter of the surface horizon is typically <1 percent dropping off quickly below. Organic matter content can be more or less depending on micro-topography.
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Shrub canopy and associated litter break raindrop impact.
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
Compacted layers are not typical. Subsoil calcic horizons are not to be interpreted as compacted.
Functional/Structural Groups (list in order of descending dominance by above-ground annual-production or live foliar cover using symbols: >>, >, = to indicate much greater than, greater than, and equal to):

Dominant:
Mojave Desert shrubs

Sub-dominant:
deep-rooted, cool-season, bunchgrasses = warm-season, bunchgrasses > perennial forbs = annual forbs

Other:

Additional:
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
Dead branches within individual shrubs common and standing dead shrub canopy material may be as much as 25% of total woody canopy; some of the mature bunchgrasses (<10%) have dead centers.
Average percent litter cover (%) and depth ( in):
Between plant interspaces up to 5%.
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
For normal or average growing season ± 200 lbs/ac.
Potential invasive (including noxious) species (native and non-native). List species which BOTH characterize degraded states and have the potential to become a dominant or co-dominant species on the ecological site if their future establishment and growth is not actively controlled by management interventions. Species that become dominant for only one to several years (e.g., short-term response to drought or wildfire) are not invasive plants. Note that unlike other indicators, we are describing what is NOT expected in the reference state for the ecological site:
Red brome, Mediterranean grass and red-stem filaree are invaders on this site.
Perennial plant reproductive capability:
All functional groups should reproduce in average (or normal) and above average growing season years.

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