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Ecological site R030XB098NV

GRAVELLY OUTWASH

Last updated: 2/26/2025
Accessed: 06/18/2026

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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 is found on inset fans below 3600 feet where headwaters within the watershed are also below 3600 feet. These low elevations have a Plant Hardiness Zone 9b or warmer so that smoketree, typically found in the Sonoran Desert, is often present in these fluves. Colder weather events likely exclude other Sonoran species, excluding this section of the Mojave from the Sonoran Desert.

This is a group concept and provisional STM that also covers R030XY228CA, RO30XC011NV

Associated sites

R030XB005NV	Arid Active Alluvial Fans
R030XB019NV	Eroded Fan Remnant Pavette 4-6 P.Z.
R030XB028NV	VALLEY WASH

R030XB005NV

Arid Active Alluvial Fans

R030XB019NV

Eroded Fan Remnant Pavette 4-6 P.Z.

R030XB028NV

VALLEY WASH

Similar sites

R030XB051NV	UPLAND WASH Higher elevations; ENFA minor spp., if present
R030XY047NV	ALLUVIAL PLAIN ATPO dominant shrub
R030XY046NV	OUTWASH PLAIN ATPO-AMDU2 codominant shrubs
R030XB028NV	VALLEY WASH More productive site; ENFA absent to minor shrub

Table 1. Dominant plant species

Tree	Not specified
Shrub	(1) Ambrosia dumosa (2) Encelia farinosa
Herbaceous	(1) Pleuraphis rigida

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Physiographic features

This site occurs within inset fans on the outer margins of ephemeral stream drainageways. Slope gradients of 2 to 8 percent are typical. Elevations are 550 to about 3000 feet.

Table 2. Representative physiographic features

Landforms	(1) Inset fan (2) Drainageway
Flooding duration	Extremely brief (0.1 to 4 hours) to very brief (4 to 48 hours)
Flooding frequency	Very rare to occasional
Elevation	550 – 3000 ft
Slope	2 – 8 %
Aspect	Aspect is not a significant factor

Climatic features

The climate of the Mojave Desert has extreme fluctuations of daily temperatures, strong seasonal winds, and clear skies. The climate is arid and is characterized with cool, moist winters and hot, dry summers. Most of the rainfall falls between November and April. Summer convection storms from July to September may contribute up to 25 percent of the annual precipitation. Average annual precipitation is 3 to 7 inches. Mean annual air temperature is 57 to 69 degrees F. The average growing season is about 180 to 340 days.

Table 3 Representative climatic features

Frost-free period (average)	340 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 very deep alluvium derived from mixed sources. Textures are stratified extremely gravelly coarse sands and very gravelly coarse sands. The soils are modified throughout by high amounts of gravels, cobbles, and stones. Water intake rates are high, available water capacity is low to very low, runoff is negligible to very low and the soils are excessively drained. Soil series associated with this site include Carrizo and Huevi.

Table 4. Representative soil features

Surface texture	(1) Very cobbly coarse sand (2) Extremely gravelly sand
Family particle size	(1) Sandy
Drainage class	Well drained to excessively drained
Permeability class	Moderate to very rapid
Soil depth	72 – 84 in
Surface fragment cover <=3"	20 – 70 %
Surface fragment cover >3"	5 – 10 %
Available water capacity (0-40in)	1.6 – 2 in
Calcium carbonate equivalent (0-40in)	0 – 25 %
Electrical conductivity (0-40in)	0 – 4 mmhos/cm
Sodium adsorption ratio (0-40in)	0 – 5
Soil reaction (1:1 water) (0-40in)	7.4 – 9
Subsurface fragment volume <=3" (Depth not specified)	20 – 62 %
Subsurface fragment volume >3" (Depth not specified)	3 – 15 %

Ecological dynamics

Ephemeral streams are unique in that they lack permanent flow although they perform the same critical hydrologic functions as perennial streams; they move water, sediment, nutrients and debris through the stream network and provide connectivity within the watershed. These systems experience extreme and rapid variations in flood magnitudes as a response to heavy rain events. The fundamental difference between ephemeral and perennial streams is that ephemeral stream channels have sizeable transmission losses when they flow. Ephemeral streams are also characterized by wider channels, low sinuosity, and flat bed topography. The sparseness of vegetation along the stream banks contributes to channel widening tendencies. (Levick et al 2008).

Along the desert washes, vegetation composition and structure overlap considerably with those of the surrounding desert uplands. An example of this is creosotebush and white bursage commonly occur in the washes and adjoining uplands. As water availability increases, the vegetation becomes increasingly distinct from the upland vegetation with respect of physiognomy and species composition. Canopy cover increases and mesoriparian and hydroriparian species increase in abundance (Levick et al 2008). The four wash ecological sites are characterized as having intermediate water availability and support more drought-tolerant shrubs.

As a result of decreased flow rates in the downstream direction, more silts and fines are deposited in the channel, which can be advantageous to biotic communities. Many of the species (white burrobush, desert rabbitbrush, baccharis, sweetbush) occurring on these sites are generally considered to be increasers or pioneers in the presence of disturbance (Abella 2010). These species produce prolific numbers of wind-dispersed seeds and are more abundant in ephemeral streams with intense flood scour (Levick et al 2008). Rainfall and flood flow events can trigger a pulse of germination of annual and perennial forbs from a diverse soil seed bank. Some species, such as catclaw acacia, desert willow, purple sage (Salvia dorrii), and bladdersage (Salazaria mexicana) have resprouting capabilities; an adaptation to withstand flooding flows. Catclaw acacia also has nitrogen fixing bacteria associated with its roots, which can be an important influence on local nitrogen availability. The increased availability of nutrients on these sites compared to the surrounding area increases the likelihood of encountering invasive species, like saltcedar (Tamarix spp.). Saltcedar is successful in arid environments due to its ability to tolerate unpredictable periods of moisture. Perturbation of these systems by natural or anthropogenic causes can result in the development of continuous incised channels.

Flooding is a natural disturbance within these ecological sites due to their location on the landscape. Floods help to redistribute nutrients across the landscape, as well as, encouraging resprouting and seedling establishment. Seedling establishment and canopy expansion is greater for plants growing in the drainageways than the surrounding area. However, these plants are less tolerant of extended dry periods because they are adapted to increased soil moisture (Hamerlynk and McAuliffe 2008). Very large rainfall events rarely occur but have the potential to remove existing vegetation and deposit new sediment, initiating secondary succession.

Ephemeral stream channels are more sensitive to disturbance than their perennial counterparts. Recreational activities, especially OHV use remove the protective vegetative cover, and change the sediment transport relationship in these systems. Loss of vegetative cover leaves channels more susceptible to entrenchment and channel widening resulting in habitat loss. In order for restoration attempts to succeed, it is important to wait until the system has reached a new dynamic equilibrium. Once the system has stabilized restoration steps should include removal of disturbance, control of non-natives and allow natural regeneration or plant natives (Briggs 1996).

Wildfire is infrequent and patchy in this system. However, years with increased annual precipitation result in increased production from annuals and increase the chances of wildfire. Post fire creosotebush, baccharis and other fire intolerant shrubs decrease. Fire tolerant species such as bursage, burrowbrush, ephedra, desert willow and acacia are able to sprout from the root crown and may increase following wildfire. Fire also favors an increase by perennial native grasses.

State and transition model

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Click on state and transition labels to scroll to the respective text

State 1
Reference State

This state represents the natural range of variability under pristine conditions. Plant community phase changes are maintained by occasional flooding in response to heavy rainfall events, periodic drought and insect attack. Fire is rare in this system, but can have long term impacts on plant community composition. Timing of disturbances combined with weather events determines plant community dynamics.

Community 1.1
Reference Plant Community

The reference plant community is representative of a healthy climax condition. Vegetation is dominated by white brittlebush and white bursage. Potential vegetative composition is about 30% grasses, 10% perennial and annual forbs, and 60% shrubs. Approximate ground cover (basal and crown) is 10 to 20 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	270	420	600
Grass/Grasslike	135	210	300
Forb	45	70	100
Total	450	700	1000

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.

Dominant shrubs persist after invasion by non-native annuals, but the other shrubs and desirable grasses may be unsuccessful in competing with the non-natives. A biotic threshold has been crossed with the introduction of non-native annuals that cannot be removed from the system. Ecological resiliency has been reduced by the presence of non-native species that have the potential to alter disturbance regimes significantly from their natural or historic range of disturbances. In addition to non-native annual grasses like Mediterranean grass and red brome, this site is also susceptible to invasion by saltcedar.

Community 2.1
Plant Community Phase 2.1

This plant community is compositionally similar to the Reference Plant Community with a trace of non-natives in the understory. Ecologic function has not been compromised at this time, however resilience is reduced by the presence of non-natives.

Community 2.2
Plant Community Phase 2.2

This plant community is characterized as “at-risk”. The decrease in long-lived perennial shrubs has reduced the stability of the site, leaving it vulnerable to increased erosion. Natural ecosystem processes are disrupted sediment and nutrients are increasingly redistributed downstream.

Pathway 2.1a
Community 2.1 to 2.2

Increased disturbance from OHV use or other impacts removes long-lived shrubs and favors short-lived species and non-native annuals.

Pathway 2.2a
Community 2.2 to 2.1

With time and removal of disturbance long-lived perennial species return and ecosystem is restored.

State 3
Eroded State

The Eroded State is characterized by increased channel erosion. An abiotic threshold has been crossed, triggered by chronic disturbance or even a discrete event such as an intense rainfall event, leading to sediment transport and the loss of perennial vegetation.

Community 3.1
Plant Community Phase 3.1

This plant community is dominated by short-lived perennial shrubs and non-natives, characteristic of a short disturbance return interval. The ability of this site to dissipate energy during large flow event is severely reduced contributing to ecological damage downstream.

Community 3.2
Plant Community Phase 3.2

This plant community is characterized by a loss of stability, increased erosion, and channel incision. Ecological processes have been altered including connectivity within the watershed, ground water recharge and habitat quality.

Pathway 3.1a
Community 3.1 to 3.2

Large scale disturbance removes remaining perennial shrubs.

Pathway 3.2a
Community 3.2 to 3.1

With time and the exclusion of disturbance some perennial plants return to the system increasing stability.

Transition 1
State 1 to 2

Introduction of non-native species due to anthropogenic impacts including OHV use, dry land farming, grazing, linear corridors, mining, military operations, and settlements.

Transition 2
State 2 to 3

Large scale disturbance on a short return interval remove stabilizing vegetation and lead to increased erosion.

Restoration pathway 3
State 3 to 2

Restoration pathway. Ecological processes can be restored to the site, but non-natives remain. Possible restoration techniques include stabilizing the site by reestablishing native perennials and the use of artificial rip-rap to dissipate energy and reestablish the flood plain.

Additional community tables

Table 6. Community 1.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)
Grass/Grasslike
1	Primary Perennial Grasses			105–175
	big galleta	PLRI3	Pleuraphis rigida	105–175	–
2	Secondary Perennial Grasses			14–70
	Indian ricegrass	ACHY	Achnatherum hymenoides	4–21	–
	desert needlegrass	ACSP12	Achnatherum speciosum	4–21	–
	threeawn	ARIST	Aristida	4–21	–
3	Annual Grasses			1–21
Forb
4	Perennial Forbs			14–70
	hoary tansyaster	MACA2	Machaeranthera canescens	14–70	–
5	Annual Forbs			1–105
Shrub/Vine
6	Primary Shrubs			286–616
	burrobush	AMDU2	Ambrosia dumosa	174–280	–
	brittlebush	ENFA	Encelia farinosa	35–140	–
	sweetbush	BEJU	Bebbia juncea	35–70	–
	creosote bush	LATR2	Larrea tridentata	14–56	–
	burrobrush	HYSA	Hymenoclea salsola	14–35	–
	ratany	KRAME	Krameria	14–35	–
7	Secondary Shrubs			15–30
	catclaw acacia	ACGR	Acacia greggii	7–35	–
	desert willow	CHLI2	Chilopsis linearis	7–35	–
	jointfir	EPHED	Ephedra	7–35	–
	Eastern Mojave buckwheat	ERFAP	Eriogonum fasciculatum var. polifolium	7–35	–
	beavertail pricklypear	OPBA2	Opuntia basilaris	7–35	–
	Fremont's dalea	PSFR	Psorothamnus fremontii	7–35	–
	Mexican bladdersage	SAME	Salazaria mexicana	7–35	–
	Mojave yucca	YUSC2	Yucca schidigera	7–35	–

Table 7. Community 2.1 plant community composition

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

Table 8. Community 2.2 plant community composition

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

Table 9. Community 3.1 plant community composition

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

Table 10. Community 3.2 plant community composition

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

Interpretations

Animal community

Livestock Interpretations:
This site is suitable for livestock grazing. Grazing management should be keyed to perennial grasses or palatable shrub production. White bursage is an important browse species. Browsing pressure on white bursage is particularly heavy during years of low precipitation, when production of winter annuals is low. White bursage is of intermediate forage value. It is fair to good forage for horses and fair to poor for cattle and sheep. However, because there is often little other forage where white bursage grows, it is often highly valuable to browsing animals. White brittlebush has no forage value for domestic livestock. Many animals bed in or under creosotebush. Domestic sheep dig shallow beds under creosotebush because it provides the only shade in the desert scrub community. Creosotebush is unpalatable to livestock. Consumption of creosotebush may be fatal to sheep. Range ratany is an important forage species for all classes of livestock. Palatability of range ratany is rated fair to good for cattle and sheep. Big galleta is considered a valuable forage plant for cattle and domestic sheep. Its coarse, rigid culms make it relatively resistant to heavy grazing and trampling.
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:
White bursage is an important browse species for wildlife. White brittlebush is a browse species for mule deer and desert bighorn sheep. Many small mammals browse creosotebush or consume its seeds. Desert reptiles and amphibians use creosotebush as a food source and perch site and hibernate or estivate in burrows under creosotebush, avoiding predators and excessive daytime temperatures. Range ratany is an important forage species for deer. Mule deer browse range ratany year-long with seasonal peaks. Mule deer peak use is from February to April and from August to October. In southern Nevada, big galleta is heavily utilized by bighorn sheep and in some blackbrush communities it is referred to as preferred habitat. Mule deer utilize trace amounts of big galleta.

Hydrological functions

Runoff is negligible to very low. Permeability is moderate to very 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 for photographers and for nature study.

Other products

White bursage is a host for sandfood, a parasitic plant with a sweet, succulent, subterranean flowerstalk. Sandfood was a valuable food supply for Native Americans. Creosotebush has been highly valued for its medicinal properties by desert peoples. It has been used to treat at least 14 illnesses. Twigs and leaves may be boiled as tea, steamed, pounded into a powder, pressed into a poultice, or heated into an infusion. The Native Americans used white burrobrush twigs and stems in several remedies. The twigs or leaves are mixed with all-thorn twigs, boiled, and the tea taken to treat skin rashes. The tea was used to relieve pain in the lungs and trachea, and to reduce swelling. Additionally, they use white burrobrush as a remedy for rheumatism.

Other information

White bursage and creosotebush may be used to revegetate disturbed sites in southwestern deserts. Once established, creosotebush may improve sites for annuals that grow under its canopy by trapping fine soil, organic matter, and symbiont propagules. It may also increase water infiltration and storage. Big galleta's clumped growth form stabilizes blowing sand.

Supporting information

Type locality

Location 1: Clark County, NV
Township/Range/Section	T30S R66E S8
General legal description	Outer margins of active channels within Empire Wash, Lake Mead National Recreation Area, Clark County, Nevada.

Other references

Abella, S.R. 2010. Disturbance and plant succession in the Mojave and Sonoran Desert of the American Southwest. Int. J. Environ. Res. Public Health. 7: 1248-1284.

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

Hamerlynck, E.P. and J.R. McAuliffe. 2008. Soil-dependent canopy die-back and plant mortality in two Mojave Desert shrubs. J. of Arid Environments. 72:1793-1802.

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

Jennings, W.B. 1997. Habitat use and food preferences of the desert tortoise, Gopherus agassizii, in the western Mojave Desert and impacts of off-road vehicles. pp. 42-45 in Proceedings: Conservation, Restoration, and Management of Tortoises and Turtles, An International Conference.

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.

Levick, L.R., D.C Goodrich, M. Hernandez, J. Fonseca, D.J. Semmens, J. Stromberg, M. Tluczek, R.A. Leidy, M. Scianni, D.P. Guertin, and W.G. Kepner. 2008. The Ecological and Hydrological Significance of Ephemeral and Intermittent Streams in the Arid and Semi-arid American Southwest. U.S. Environmental Protection Agency. Office of Research and Development.Washington D.C.

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, 2/26/2025

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	07/19/2010
Approved by
Approval date
Composition (Indicators 10 and 12) based on	Annual Production

Indicators

Number and extent of rills:
Rills are none to rare.
Presence of water flow patterns:
Water flow patterns are common.
Number and height of erosional pedestals or terracettes:
Pedestals are none to rare.
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
Bare Ground to 20%; surface rock fragments to 70%; shrub canopy 5-10%.
Number of gullies and erosion associated with gullies:
None
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) and Persistent litter (large woody material), expected to move distance of slope length during intense summer storms.
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 1 to 3 on the sandy 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 massive to weak thick platy. Soil surface colors are light and soils are typified by an ochric epipedon. Organic matter of the surface 2 to 3 inches is typically less than 1 percent.
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Perennial herbaceous plants (especially deep-rooted bunchgrasses [i.e., big gallets] slow runoff and increase infiltration. 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):
None
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, warm season, perennial bunchgrasses >> annual forbs > deep-rooted, cool season, perennial bunchgrasses > perennial forbs > annual grasses

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 (<20%) have dead centers.
Average percent litter cover (%) and depth ( in):
Between plant interspaces (15-25%) and depth of litter is ±¼ inch.
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
For normal or average growing season ±700 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:
Invaders on this site include Mediterranean grass, red brome, filaree, salt cedar, and mustards.
Perennial plant reproductive capability:
All functional groups should reproduce in average (or normal) and above average growing season years.

Download reference sheet

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