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Ecological site R040XA103AZ

Clayey Slopes 10"-13" p.z.

Accessed: 11/24/2024

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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.

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Figure 1. Mapped extent

Areas shown in blue indicate the maximum mapped extent of this ecological site. Other ecological sites likely occur within the highlighted areas. It is also possible for this ecological site to occur outside of highlighted areas if detailed soil survey has not been completed or recently updated.

MLRA notes

Major Land Resource Area (MLRA): 040X–Sonoran Basin and Range

AZ 40.1 – Upper Sonoran Desert

Elevations range from 2000 to 3200 feet and precipitation averages 10 to 13 inches per year. Vegetation includes saguaro, palo verde, mesquite, creosotebush, triangle bursage, prickly pear, cholla, limberbush, wolfberry, bush muhly, threeawns, ocotillo, and globe mallow. The soil temperature regime is thermic and the soil moisture regime is typic aridic. This unit occurs within the Basin and Range Physiographic Province and is characterized by numerous mountain ranges that rise abruptly from broad, plain-like valleys and basins. Igneous and metamorphic rock classes dominate the mountain ranges and sediments filling the basins represent combinations of fluvial, lacustrine, colluvial and alluvial deposits.

Associated sites

R040XA101AZ	Basalt Hills 10"-13" p.z.
R040XA110AZ	Limy Slopes 10"-13" p.z.
R040XA113AZ	Loamy Slopes 10"-13" p.z.
R040XA123AZ	Volcanic Hills 10"-13" P.Z.

Similar sites

R038XA108AZ	Clayey Slopes 12-16" p.z.
R041XC303AZ	Clayey Slopes 12-16" p.z.

R038XA108AZ

Clayey Slopes 12-16" p.z.

R041XC303AZ

Clayey Slopes 12-16" p.z.

Table 1. Dominant plant species

Tree	(1) Parkinsonia microphylla
Shrub	(1) Calliandra eriophylla (2) Simmondsia chinensis
Herbaceous	(1) Pleuraphis mutica (2) Hilaria belangeri

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Physiographic features

This site occurs in the upper elevations of the Sonoran Desert in southern Arizona. Slope aspect is site differentiating at elevations near common resource area boundaries.

Table 2. Representative physiographic features

Landforms	(1) Hill (2) Ridge
Flooding frequency	None
Ponding frequency	None
Elevation	671 – 1,067 m
Slope	15 – 45%
Aspect	N, E, S

Climatic features

Precipitation in the sub resource area ranges from 10 to 13 inches in the southern part, along the Mexican border with elevations from about 1900 to 3200 feet. Precipitation in the northern part of the resource area ranges from 11 to 14 inches with elevations from about 1700 to 3500 feet. Winter-summer rainfall ratios range from 40%-60% in the southern portions of the land resource unit, to 50%-50% in the central portions, to 60%-40% in the northern part of the land resource unit. As one moves from east to west in this resource area rains become slightly more unpredictable and variable with Coefficients of Variation of annual rainfall equal to 29% at Tucson and 36% at Carefree. Summer rains fall July through Sept., originate in the Gulf of Mexico, and are convective, usually brief, intense thunderstorms. Cool season moisture tends to be frontal, originating in the Pacific and Gulf of California. This winter precipitation falls in widespread storms with long duration and low intensity. Snow is rare and seldom lasts more than an hour or two. May and June are the driest months of the year. Humidity is generally very low.

Winter temperatures are mild, with very few days recording freezing temperatures in the morning. Summer temperatures are warm to hot, with several days in June and July exceeding 105 degrees F.

Both the spring and the summer growing seasons are equally important for perennial grass, forb and shrub growth. Cool and warm season annual forbs and grasses can be common in their respective seasons with above average rainfall. Perennial forage species can remain green throughout the year with available moisture.

Table 3. Representative climatic features

Frost-free period (average)	265 days
Freeze-free period (average)	0 days
Precipitation total (average)	330 mm

Bar

Line

Figure 2. Monthly precipitation range

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Figure 3. Monthly average minimum and maximum temperature

Soil features

These are deep to shallow soils which have formed in gravelly, clayey alluvium and colluvium, or in place on shale. Soil surfaces are well protected by gravels and rocks. They are non calcareous, but calcareous horizons or bedrock can occur at moderate to shallow depths. Plant-soil moisture relationships are between good. Soil mapped on this site include: SSA-661 Eastern Pinal/Southern Gila Counties MU Granolite-465.

Table 4. Representative soil features

Surface texture	(1) Very gravelly sandy loam (2) Cobbly sandy loam (3) Very gravelly loam
Family particle size	(1) Clayey
Drainage class	Well drained
Permeability class	Moderately slow to slow
Soil depth	51 – 152 cm
Surface fragment cover <=3"	20 – 60%
Surface fragment cover >3"	5 – 20%
Available water capacity (0-101.6cm)	7.62 – 17.78 cm
Calcium carbonate equivalent (0-101.6cm)	0 – 10%
Electrical conductivity (0-101.6cm)	0 – 2 mmhos/cm
Sodium adsorption ratio (0-101.6cm)	0 – 2
Soil reaction (1:1 water) (0-101.6cm)	7.4 – 8.4
Subsurface fragment volume <=3" (Depth not specified)	30 – 60%
Subsurface fragment volume >3" (Depth not specified)	0 – 10%

Ecological dynamics

The plant communities found on an ecological site are naturally variable. Composition and production will vary with yearly conditions, location, aspect, and the natural variability of the soils. The Historical Climax Plant Community represents the natural potential plant communities found on relict or relatively undisturbed sites. Other plant communities described here represent plant communities that are known to occur when the site is disturbed by factors such as fire, grazing, or drought.

Production data provided in this site description is standardized to air dry weight at the end of the summer growing season. The plant communities described in this site description are based on near normal rainfall years.

NRCS uses a Similarity Index to compare existing plant communities to the plant communities described here. Similarity Index is determined by comparing the production and composition of a plant community to the production and composition of a plant community described in this site description. To determine Similarity Index, compare the production (air dry weight) of each species to that shown in the plant community description. For each species, count no more than the maximum amount shown for the species, and for each group, count no more than the maximum amount shown for the group. Divide the resulting total by the total normal year production shown in the plant community description. If the rainfall has been significantly above or below normal, use the total production shown for above or below normal years. If field data is not collected at the end of the summer growing season, then the field data must be corrected to the end of the year production before comparing it to the site description. The growth curve can be used as a guide for estimating production at the end of the summer growing season.

State and transition model

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Standard diagram

Figure 4. State and Transition model, Clayey Slopes 10-13" p

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More interactive model formats are also available. View Interactive Models
Click on state and transition labels to scroll to the respective text

State 1
Historic Climax Plant Community

Community 1.1
Historic Climax Plant Community

The potential plant community on this site is an even mixture of desert shrubs, trees, cacti and perennial grasses. Annual forbs and grasses can be abundant in wet seasons. The aspect is a shrub dotted grassland. The combination of drought, fire and continuous grazing can deplete the dominant species tobosa grass. As the cover of tobosa declines curly mesquite will increase to dominate but will diminish again greatly in drought. As the perennial grass cover is thinned and shrubs like snakeweed, prickley pear and turpentine bush can increase to dominate the overstory. Jojoba is stable on the site unless repeated fires remove it. Trees tend to be shrubby on the site due to clayey textures at nor near the surface.

Figure 5. Annual production by plant type (representative values) or group (midpoint values)

Table 5. Annual production by plant type

Plant type	Low (kg/hectare)	Representative value (kg/hectare)	High (kg/hectare)
Grass/Grasslike	58	280	706
Shrub/Vine	84	224	375
Forb	12	34	224
Tree	17	56	112
Total	171	594	1417

Table 6. Soil surface cover

Tree basal cover	0-1%
Shrub/vine/liana basal cover	1-3%
Grass/grasslike basal cover	1-2%
Forb basal cover	0-1%
Non-vascular plants	0%
Biological crusts	0-5%
Litter	15-75%
Surface fragments >0.25" and <=3"	30-75%
Surface fragments >3"	1-30%
Bedrock	0%
Water	0%
Bare ground	5-50%

Table 7. Canopy structure (% cover)

Height Above Ground (m)	Tree	Shrub/Vine	Grass/ Grasslike	Forb
<0.15	–	0-1%	0-20%	0-15%
>0.15 <= 0.3	–	0-1%	15-15%	1-15%
>0.3 <= 0.6	–	1-2%	10-35%	0-5%
>0.6 <= 1.4	0-1%	5-15%	0-1%	–
>1.4 <= 4	2-10%	0-1%	–	–
>4 <= 12	–	–	–	–
>12 <= 24	–	–	–	–
>24 <= 37	–	–	–	–
>37	–	–	–	–

Figure 6. Plant community growth curve (percent production by month). AZ4013, 40.1 10-13" p.z. other sites. Growth begins in the late winter, goes semi-dormant in the drought period of late May through early July, growth continues in the summer through early fall..

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
J	F	M	A	M	J	J	A	S	O	N	D
0	5	10	20	15	0	5	20	15	5	5	0

State 2
Native trees, shrubs, cacti and grass with fire

Community 2.1
Native trees, shrubs, cacti and grass with fire

This plant community occurs as a result of a single hot season fire. Paloverde and saguaro can be severely impacted and may take long periods of time (30-50 years) to recover to pre-fire levels. Perennial and annual grasses and forbs dominate the community for some time until shrubs like jojoba and triangle bursage can recover. This plant community can produce enough herbaceous fuel from native species of grasses and / or forbs to carry fire in El Nino years or after unusually wet summers. The natural incidence of fire in this MLRA is very low and fires are much more common from man-made ignitions. Areas of the site close to urban zones or along heavily travelled roads and highways will experience a higher rate of fires.

State 3
Exotic perennial grasses with natives

Community 3.1
Exotic perennial grasses with natives

This community occurs where bufflegrass, natal grass or fountain grass invade the native plant community. These species occupy the niches of low shrubs like triangle bursage, grasses like tobosa and curley mesquite and woody forbs like janusia and twinberry.

State 4
Exotic perennial grasses and fire

Community 4.1
Exotic perennial grasses and fire

This community occurs where a native plant community that has been invaded by bufflegrass has burned one or more times. Increasing amounts of bufflegrass leads to more uniform fine fuels. In areas adjacent to roads and urban areas the risk of repeated fires will increase. As fire frequency increases the dominance of the exotic grasses increase.

State 5
Native plant community with exotic annuals

Community 5.1
Native plant community with exotic annuals

This plant community occurs where the native community has been invaded by red brome, filaree and / or schismus. Red brome occupies the niche of the native winter annual forbs and grasses. This exotic annual grass will fluctuate from nearly nothing in a dry winter to dominance of the understory plant community in a El Nino winter.

State 6
Exotic annuals and fire

Community 6.1
Exotic annuals and fire

This plant community occurs where a native plant community which has been invaded by red brome and / or schismus has burned repeatedly. As fires become more frequent the native trees, shrubs and succulents are removed from the plant community and red brome becomes dominant. In areas of the site near urban areas and along heavily travelled roads this will be a more common occurence due to an increased source of ignitions.

Additional community tables

Table 8. Community 1.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production (kg/hectare)	Foliar cover (%)
Grass/Grasslike
1	Dominant mid grass			56–336
	tobosagrass	PLMU3	Pleuraphis mutica	56–336	–
2	Dominant short grass			1–112
	curly-mesquite	HIBE	Hilaria belangeri	1–112	–
3	Misc perennial grasses			0–34
	purple threeawn	ARPU9	Aristida purpurea	0–22	–
	sideoats grama	BOCU	Bouteloua curtipendula	0–17	–
	tanglehead	HECO10	Heteropogon contortus	0–11	–
	Parish's threeawn	ARPUP5	Aristida purpurea var. parishii	0–11	–
	spidergrass	ARTE3	Aristida ternipes	0–11	–
	spidergrass	ARTEG	Aristida ternipes var. gentilis	0–11	–
	cane bluestem	BOBA3	Bothriochloa barbinodis	0–6	–
	squirreltail	ELELE	Elymus elymoides ssp. elymoides	0–2	–
4	Annual grasses			1–224
	sixweeks threeawn	ARAD	Aristida adscensionis	1–112	–
	mucronate sprangeltop	LEPAB	Leptochloa panicea ssp. brachiata	0–112	–
	Mexican panicgrass	PAHI5	Panicum hirticaule	0–112	–
	sixweeks fescue	VUOC	Vulpia octoflora	0–56	–
	little barley	HOPU	Hordeum pusillum	0–56	–
	Pacific fescue	VUMIP	Vulpia microstachys var. pauciflora	0–17	–
	prairie threeawn	AROL	Aristida oligantha	0–11	–
	needle grama	BOAR	Bouteloua aristidoides	0–11	–
	Rothrock's grama	BORO2	Bouteloua rothrockii	0–11	–
	sixweeks grama	BOBA2	Bouteloua barbata	0–6	–
	Mexican sprangletop	LEFUU	Leptochloa fusca ssp. uninervia	0–6	–
	Bigelow's bluegrass	POBI	Poa bigelovii	0–6	–
	delicate muhly	MUFR	Muhlenbergia fragilis	0–2	–
	littleseed muhly	MUMI	Muhlenbergia microsperma	0–2	–
	Arizona brome	BRAR4	Bromus arizonicus	0–1	–
	feather fingergrass	CHVI4	Chloris virgata	0–1	–
Forb
5	Perennial forbs			11–56
	slender janusia	JAGR	Janusia gracilis	1–17	–
	desert globemallow	SPAM2	Sphaeralcea ambigua	1–17	–
	brownplume wirelettuce	STPA4	Stephanomeria pauciflora	0–11	–
	bluedicks	DICA14	Dichelostemma capitatum	0–11	–
	spreading fleabane	ERDI4	Erigeron divergens	0–6	–
	largeflower onion	ALMA4	Allium macropetalum	0–6	–
	weakleaf bur ragweed	AMCO3	Ambrosia confertiflora	1–6	–
	tuber anemone	ANTU	Anemone tuberosa	1–6	–
	lacy tansyaster	MAPIP4	Machaeranthera pinnatifida ssp. pinnatifida var. pinnatifida	0–6	–
	slender poreleaf	POGR5	Porophyllum gracile	0–6	–
	glandleaf milkwort	POMA7	Polygala macradenia	0–2	–
	wishbone-bush	MILAV	Mirabilis laevis var. villosa	0–2	–
	red-gland spurge	CHME5	Chamaesyce melanadenia	0–2	–
	dwarf desertpeony	ACNA2	Acourtia nana	0–2	–
	brownfoot	ACWR5	Acourtia wrightii	0–1	–
	San Felipe dogweed	ADPO	Adenophyllum porophylloides	0–1	–
	spearleaf	MAPA9	Matelea parvifolia	0–1	–
	desert rosemallow	HICO	Hibiscus coulteri	0–1	–
	Indian rushpea	HOGL2	Hoffmannseggia glauca	0–1	–
	leatherweed	CRPOP	Croton pottsii var. pottsii	0–1	–
	desert larkspur	DEPA	Delphinium parishii	0–1	–
	tall mountain larkspur	DESC	Delphinium scaposum	0–1	–
	Braun's rockcress	ARPE3	Arabis perstellata	0–1	–
	dense ayenia	AYMI	Ayenia microphylla	0–1	–
	desert tobacco	NIOBO	Nicotiana obtusifolia var. obtusifolia	0–1	–
	Parry's beardtongue	PEPA24	Penstemon parryi	0–1	–
	orange fameflower	PHAU13	Phemeranthus aurantiacus	0–1	–
	Coues' cassia	SECO10	Senna covesii	0–1	–
	spreading fanpetals	SIAB	Sida abutifolia	0–1	–
	silverleaf nightshade	SOEL	Solanum elaeagnifolium	0–1	–
	Coulter's wrinklefruit	TECO	Tetraclea coulteri	0–1	–
	caliche globemallow	SPLA	Sphaeralcea laxa	0–1	–
	Palmer's Indian mallow	ABPA	Abutilon palmeri	0–1	–
6	Annual forbs			1–168
	California poppy	ESCAM	Eschscholzia californica ssp. mexicana	0–112	–
	coastal bird's-foot trefoil	LOSA	Lotus salsuginosus	0–56	–
	western tansymustard	DEPI	Descurainia pinnata	0–56	–
	Arizona popcornflower	PLAR	Plagiobothrys arizonicus	0–56	–
	smallflowered milkvetch	ASNU4	Astragalus nuttallianus	0–34	–
	shaggyfruit pepperweed	LELA	Lepidium lasiocarpum	0–34	–
	Arizona poppy	KAGR	Kallstroemia grandiflora	0–34	–
	fringed redmaids	CACI2	Calandrinia ciliata	0–28	–
	pitseed goosefoot	CHBE4	Chenopodium berlandieri	0–28	–
	bristly fiddleneck	AMTE3	Amsinckia tessellata	0–28	–
	desert Indianwheat	PLOV	Plantago ovata	0–22	–
	New Mexico plumeseed	RANE	Rafinesquia neomexicana	0–22	–
	mesa tansyaster	MATA	Machaeranthera tagetina	0–17	–
	tanseyleaf tansyaster	MATA2	Machaeranthera tanacetifolia	0–17	–
	woolly plantain	PLPA2	Plantago patagonica	0–17	–
	combseed	PECTO	Pectocarya	0–17	–
	distant phacelia	PHDI	Phacelia distans	0–17	–
	thelypody	THELY	Thelypodium	0–17	–
	Louisiana vetch	VILU	Vicia ludoviciana	0–17	–
	fringed amaranth	AMFI	Amaranthus fimbriatus	0–17	–
	carelessweed	AMPA	Amaranthus palmeri	0–17	–
	wedgeleaf draba	DRCU	Draba cuneifolia	0–17	–
	Abert's buckwheat	ERAB2	Eriogonum abertianum	0–17	–
	miniature woollystar	ERDI2	Eriastrum diffusum	0–17	–
	foothill deervetch	LOHU2	Lotus humistratus	0–17	–
	California desertdandelion	MACA6	Malacothrix californica	0–11	–
	Esteve's pincushion	CHST	Chaenactis stevioides	0–11	–
	pincushion flower	CHFR	Chaenactis fremontii	0–11	–
	yellow tackstem	CAPA7	Calycoseris parryi	0–11	–
	white tackstem	CAWR	Calycoseris wrightii	0–11	–
	sleepy silene	SIAN2	Silene antirrhina	0–11	–
	Lindley's silverpuffs	MILI5	Microseris lindleyi	0–11	–
	Nuttall's povertyweed	MONU	Monolepis nuttalliana	0–6	–
	desert evening primrose	OEPR	Oenothera primiveris	0–6	–
	manybristle chinchweed	PEPA2	Pectis papposa	0–6	–
	Arizona phacelia	PHAR13	Phacelia arizonica	0–6	–
	cleftleaf wildheliotrope	PHCR	Phacelia crenulata	0–6	–
	whitestem blazingstar	MEAL6	Mentzelia albicaulis	0–6	–
	Sonoran sandmat	CHMI7	Chamaesyce micromera	0–6	–
	cryptantha	CRYPT	Cryptantha	0–6	–
	American wild carrot	DAPU3	Daucus pusillus	0–6	–
	Thurber's buckwheat	ERTH3	Eriogonum thurberi	0–6	–
	slender goldenweed	MAGR10	Machaeranthera gracilis	0–6	–
	Coulter's lupine	LUSP2	Lupinus sparsiflorus	0–6	–
	California suncup	CACA32	Camissonia californica	0–6	–
	Goodding's bladderpod	LEGO2	Lesquerella gooddingii	0–6	–
	star gilia	GIST	Gilia stellata	0–6	–
	New Mexico thistle	CINE	Cirsium neomexicanum	0–3	–
	goosefoot	CHENO	Chenopodium	1–3	–
	hoary bowlesia	BOIN3	Bowlesia incana	0–2	–
	sand pygmyweed	CRCOC	Crassula connata var. connata	0–2	–
	dainty desert hideseed	EUMI2	Eucrypta micrantha	0–2	–
	Arizona cottonrose	LOAR12	Logfia arizonica	0–2	–
	limestone bedstraw	GAPR	Galium proliferum	0–1	–
	Mexican fireplant	EUHE4	Euphorbia heterophylla	0–1	–
	California mustard	GULA4	Guillenia lasiophylla	0–1	–
	Lemmon's ragwort	SELE8	Senecio lemmonii	0–1	–
	doubleclaw	PRPA2	Proboscidea parviflora	0–1	–
	Florida pellitory	PAFL3	Parietaria floridana	0–1	–
Shrub/Vine
7	Dominant half shrubs			17–84
	fairyduster	CAER	Calliandra eriophylla	17–28	–
	Eastern Mojave buckwheat	ERFA2	Eriogonum fasciculatum	0–17	–
	triangle bur ragweed	AMDE4	Ambrosia deltoidea	0–17	–
	bastardsage	ERWR	Eriogonum wrightii	0–11	–
	brittlebush	ENFA	Encelia farinosa	0–11	–
	button brittlebush	ENFR	Encelia frutescens	0–11	–
	littleleaf ratany	KRER	Krameria erecta	0–11	–
	rough menodora	MESC	Menodora scabra	0–11	–
	Parish's goldeneye	VIPA14	Viguiera parishii	0–11	–
	broom snakeweed	GUSA2	Gutierrezia sarothrae	0–6	–
	white ratany	KRGR	Krameria grayi	0–2	–
8	Dominant large shrubs			56–224
	jojoba	SICH	Simmondsia chinensis	45–168	–
	whitethorn acacia	ACCO2	Acacia constricta	0–22	–
	catclaw acacia	ACGR	Acacia greggii	6–22	–
	ocotillo	FOSP2	Fouquieria splendens	0–17	–
	pelotazo	ABIN	Abutilon incanum	0–6	–
9	Misc shrubs			0–6
	banana yucca	YUBA	Yucca baccata	0–6	–
	Berlandier's wolfberry	LYBE	Lycium berlandieri	0–2	–
	Warnock's snakewood	COWA	Condalia warnockii	0–2	–
	Nevada jointfir	EPNE	Ephedra nevadensis	0–1	–
	turpentine bush	ERLA12	Ericameria laricifolia	0–1	–
	sangre de cristo	JACA2	Jatropha cardiophylla	0–1	–
	rayless goldenhead	ACSP	Acamptopappus sphaerocephalus	0–1	–
	Wright's beebrush	ALWR	Aloysia wrightii	0–1	–
	lotebush	ZIOB	Ziziphus obtusifolia	0–1	–
10	Succulents			11–62
	cactus apple	OPEN3	Opuntia engelmannii	6–34	–
	saguaro	CAGI10	Carnegiea gigantea	0–22	–
	buck-horn cholla	CYAC8	Cylindropuntia acanthocarpa	1–17	–
	walkingstick cactus	CYSP8	Cylindropuntia spinosior	1–11	–
	staghorn cholla	CYVE3	Cylindropuntia versicolor	0–6	–
	jumping cholla	CYFU10	Cylindropuntia fulgida	0–6	–
	purple pricklypear	OPMA8	Opuntia macrocentra	0–6	–
	tulip pricklypear	OPPH	Opuntia phaeacantha	0–6	–
	Christmas cactus	CYLE8	Cylindropuntia leptocaulis	0–2	–
	candy barrelcactus	FEWI	Ferocactus wislizeni	0–2	–
	desert agave	AGDE	Agave deserti	0–2	–
	Arizona pencil cholla	CYAR14	Cylindropuntia arbuscula	0–1	–
	Graham's nipple cactus	MAGR9	Mammillaria grahamii	0–1	–
	Engelmann's hedgehog cactus	ECEN	Echinocereus engelmannii	0–1	–
	pinkflower hedgehog cactus	ECFA	Echinocereus fasciculatus	0–1	–
	spinystar	ESVI2	Escobaria vivipara	0–1	–
Tree
11	Trees			17–112
	yellow paloverde	PAMI5	Parkinsonia microphylla	11–112	–
	velvet mesquite	PRVE	Prosopis velutina	0–22	–
	blue paloverde	PAFL6	Parkinsonia florida	0–11	–

Interpretations

Animal community

Steep slopes and cobbly or gravelly surfaces limit grazing distribution especially in the hotter months of the year. Stocker cattle will use areas of this site fairly well at any season. Forage species grow year-round with available moisture. The plant community provides adequate nutrition for livestock throughout the year.

Water developments are very important to wildlife species on this site. Even though vegetative cover is lacking, rugged topography and forage diversity make the site home to a great variety of wildlife including the larger desert mammals.

Hydrological functions

This site is a good producer of runoff due to steep slopes and soils with argillic horizons near the surface. Very gravelly and cobbly soil surfaces tend to hold water on the site.

Recreational uses

Hunting, hiking, birdwatching, photography, horseback riding, rock hounding.

Wood products

Some paloverde, catclaw and mesquite for camp-fires and branding fires.

Other products

Stones and cobbles, clay, saguaro ribs, cholla skeletons. Tradtional foods like saguaro fruits, prickly pear tunas, cactus flower buds, grass nuts and jojoba nuts. Traditional herbs like globe mallow, wild onion and anemone.

Supporting information

Type locality

Location 1: Pima County, AZ
Township/Range/Section	T9S R18E S15
General legal description	TUCSON FIELD OFFICE - RAFTER T RANCH
Location 2: Pima County, AZ
General legal description	SELLS FIELD OFFICE - BABOQUIVARI DIST. NEAR FRESNAL VILLAGE - UNSURVEYED 111 DEGREES 41' X 31 DEGREES 48' 30"
Location 3: Pima County, AZ
Township/Range/Section	T14S R13E S15
General legal description	Tumamoc Hill, UA Desert Laboratory, inclusions of Lehmans soil in the Basalt Hills complex.

Contributors

Dan Robinett
Larry D. Ellicott

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)
Contact for lead author
Date
Approved by
Approval date
Composition (Indicators 10 and 12) based on	Annual Production

Indicators

Number and extent of rills:
Presence of water flow patterns:
Number and height of erosional pedestals or terracettes:
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
Number of gullies and erosion associated with gullies:
Extent of wind scoured, blowouts and/or depositional areas:
Amount of litter movement (describe size and distance expected to travel):
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
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:

Sub-dominant:

Other:

Additional:
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
Average percent litter cover (%) and depth ( in):
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
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:
Perennial plant reproductive capability:

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Natural ResourcesConservation Service

Ecological site R040XA103AZ

Clayey Slopes 10"-13" p.z.

Accessed: 11/24/2024

General information

Figure 1. Mapped extent

MLRA notes

Associated sites

Similar sites

Table 1. Dominant plant species

Ecosystem states

State 1 submodel, plant communities

State 2 submodel, plant communities

State 3 submodel, plant communities

State 4 submodel, plant communities

State 5 submodel, plant communities

State 6 submodel, plant communities

Natural Resources
Conservation Service