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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.Classification relationships
This site is similar to TES map unit 365 (southern exposures) on the Prescott National Forest. It is also similar to TES map units 211, 242 and 250 on the Tonto National Forest.
Associated sites
R040XA119AZ Schist Hills 10"-13" p.z.
R040XA121AZ Granitic Upland 10"-13" p.z.
R040XA123AZ Volcanic Hills 10"-13" P.Z.
Similar sites
R041XC306AZ Shallow Hills 12-16" p.z.
R040XB206AZ Shallow Hills 7"-10" p.z.
R038XA104AZ Granitic Hills 12-16" p.z.
R040XA121AZ Granitic Upland 10"-13" p.z.
Table 1. Dominant plant species
Tree (1) Parkinsonia microphylla
(2) Carnegia giganteaShrub (1) Ambrosia deltoidea
Herbaceous (1) Selaginella
(2) Janusia gracilisPhysiographic features
This site occurs in the upper elevations of the Sonoran Desert in southern Arizona. It occurs on hill-slopes and ridge-tops. Slope aspect is site differentiating at elevations near common resource area boundaries.
Table 2. Representative physiographic features
Landforms (1) Hill
(2) Ridge
(3) Mountain slope
Flooding frequency None Ponding frequency None Elevation 2200 – 4000 ft Slope 15 – 60 % 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) 270 days Freeze-free period (average) 0 days Precipitation total (average) 10 in BarLineFigure 2. Monthly precipitation range
BarLineFigure 3. Monthly average minimum and maximum temperature
">Influencing water features
There are no water features associated with this site.
Soil features
These are shallow soils formed on acid igneous parent material (granite, rhyolite) or quartzite, arkose, schist, and gneiss. Bedrock is usually slightly weathered into grus material at the soil juncture. They are non-calcareous, coarse textured, and have well developed covers of gravels and cobbles. Rock and gravel covers are light colored. Numerous areas of rock outcrop occur intermingled with soil areas. Outcrops can be as high as 25% of the area. Plant-soil moisture relationships are fair. Soils mapped on this site include: SSA-627 Southern Mohave County MU Topock-27; SSA-645 Aguila-Carefree MU's Gran-63 & Wickenburg-63; SSA-659 Western Pinal County MU Cellar-6; SSA-661 MU's Anklam-260, Cellar-250, 260, 865, Fig family-400, Gran-245 & Topock-400; SSA-669 Eastern Pima County MU's Anklam-2, Cellar-2, 13, 14 & 15 & Chimenea-15; SSA-703 Tohono O'odham MU's Anklam-2, Cellar-2 & Granolite-32.
Table 4. Representative soil features
Surface texture (1) Very gravelly sandy loam
(2) Gravelly sandy loam
(3) Very cobbly sandy loam
Family particle size (1) Loamy
Drainage class Well drained Permeability class Moderately rapid to moderate Soil depth 5 – 20 in Surface fragment cover <=3" 30 – 60 % Surface fragment cover >3" 5 – 25 % Available water capacity
(0-40in)0.6 – 2.2 in Calcium carbonate equivalent
(0-40in)0 – 5 % Electrical conductivity
(0-40in)0 – 2 mmhos/cm Sodium adsorption ratio
(0-40in)0 – 2 Soil reaction (1:1 water)
(0-40in)7.4 – 8 Subsurface fragment volume <=3"
(Depth not specified)35 – 65 % Subsurface fragment volume >3"
(Depth not specified)0 – 20 % 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
Custom diagramStandard diagram
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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 textEcosystem 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
State 1
Historical Climax Plant CommunityCommunity 1.1
Historical Climax Plant CommunityThe potential plant community is a diverse mixture of desert shrubs, trees, cacti, perennial grasses, woody forbs, and clubmoss and ferns. The aspect is shrubland.
With continuous, heavy grazing, herbaceous forage species are removed from the plant community and replaced by increases in shrubby species like triangle bursage, littleleaf paloverde, white brittlebrush, and cholla. Stone and gravel covers are continuous but size may be lacking to protect forage species from heavy utilization. Cover of club moss (SEAR2) ranges from 2 to 55% being heaviest on the cooler aspects and provides a great deal of soil stability on very steep slopes. Plant populations of major shrubs range from 200 to 800 per acre for jojoba; 10 to 100 per acre for littleleaf paloverde; 50 to 150 for ocotillo; and 650 to 1000 for the major half shrubs like brittlebush, flattop buckwheat, false mesquite, and triangle goldeneye.
North exposures have a higher percentage cover of perennial grasses and forbs than warm exposures. Grass cover ranges from 0-5% on north slopes and 0-2% on south slopes. Suffrutescent forb cover ranges from 1-20% on north slopes and 0-5% on south slopes. Warm exposures have a higher percentage of trees and succulents than north slopes. The half shrub community on north slopes is dominated by species like calliandra, eriogonum, goldeneye and mormon tea while on south slopes brittlebush, ratany, limberbush and bursage are dominant. Jojoba will have higher cover on north aspects while southern aspects will have more ocotillo, whitethorn and wolfberry. The percent of annual forbs and grasses in the plant community can range from 5% in dry years to nearly 70% in very wet winters or summers. The yearly production of annuals ranges from 10 lbs per acre to over 1200 lbs. per acre (from dry year to wet year).
Severe drought can reduce the cover of perennial grasses and suffrutescent forbs to less than 1%. Drought can also reduce the cover of sub-shrubs like brittlebush, eriogonum and bursage.
The dynamics of Saguaro on this site is unlike the 200-300 year cycle found on deep upland sites in the Upper Sonoran desert. Saguaro recruitment can occur in any favorable year due to numerous rocky habitats favorable for establishment. Saguaro populations tend to be multi-aged and persistent on this site although very favorable years for establishment may result in very heavy stands on some slopes many years later.Figure 4. 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 130 400 570 Grass/Grasslike 13 115 550 Forb 21 125 480 Tree 55 150 200 Total 219 790 1800 Table 6. Soil surface cover
Tree basal cover 0% Shrub/vine/liana basal cover 0-10% Grass/grasslike basal cover 0-0% Forb basal cover 0-0% Non-vascular plants 0% Biological crusts 0-10% Litter 10-60% Surface fragments >0.25" and <=3" 30-60% Surface fragments >3" 10-30% Bedrock 0-10% Water 0% Bare ground 10-30% Table 7. Canopy structure (% cover)
Height Above Ground (ft) Tree Shrub/Vine Grass/
GrasslikeForb <0.5 – 0-1% 0-15% 0-15% >0.5 <= 1 – 0-5% 1-10% 1-15% >1 <= 2 – 5-15% 0-5% 0-5% >2 <= 4.5 0-1% 1-10% 0-1% 0-1% >4.5 <= 13 2-15% 0-1% – – >13 <= 40 0-1% – – – >40 <= 80 – – – – >80 <= 120 – – – – >120 – – – – Figure 5. Plant community growth curve (percent production by month). AZ4011 , 40.1 10-13" p.z. hill 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 15 20 5 5 10 15 15 5 5 0 State 2
Native trees, cacti, shrubs and fireCommunity 2.1
Native trees, cacti, shrubs and fireThis 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 bursage and brittlebush 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 nativesCommunity 3.1
Exotic perennial grasses with nativesThis community occurs where bufflegrass, natal grass or fountain grass invade the native plant community. These species occupy the niches of low shrubs like brittlebush or triangle bursage and woody forbs like janusia and twinberry.
State 4
Exotic perennial grasses and fireCommunity 4.1
Exotic perennial grasses and fireThis community occurs where a native plant community that has been invaded by bufflegrass or fountain grass 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 annualsCommunity 5.1
Native plant community with exotic annualsThis plant community occurs where the native community has been invaded by red brome. 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 fireCommunity 6.1
Exotic annuals and fireThis plant community occurs where a native plant community which has been invaded by red brome 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 () Foliar cover (%) Grass/Grasslike1 Dominant perennial grasses 5–100 bush muhly MUPO2 Muhlenbergia porteri 1–30 – sideoats grama BOCU Bouteloua curtipendula 1–25 – tanglehead HECO10 Heteropogon contortus 1–25 – big galleta PLRI3 Pleuraphis rigida 0–20 – Arizona cottontop DICA8 Digitaria californica 0–15 – 2 Short perennial grasses 5–135 slender grama BORE2 Bouteloua repens 2–115 – slim tridens TRMU Tridens muticus 1–20 – 3 Miscellaneous perennial grasses 2–60 spidergrass ARTE3 Aristida ternipes 1–25 – curly-mesquite HIBE Hilaria belangeri 0–15 – Hall's panicgrass PAHA Panicum hallii 0–10 – spidergrass ARTEG Aristida ternipes var. gentilis 0–10 – desert needlegrass ACSP12 Achnatherum speciosum 0–10 – purple threeawn ARPU9 Aristida purpurea 0–10 – Parish's threeawn ARPUP5 Aristida purpurea var. parishii 1–10 – Wright's threeawn ARPUW Aristida purpurea var. wrightii 0–10 – cane bluestem BOBA3 Bothriochloa barbinodis 0–5 – black grama BOER4 Bouteloua eriopoda 0–5 – low woollygrass DAPU7 Dasyochloa pulchella 0–5 – plains bristlegrass SEVU2 Setaria vulpiseta 0–5 – sand dropseed SPCR Sporobolus cryptandrus 0–5 – mesa dropseed SPFL2 Sporobolus flexuosus 0–5 – green sprangletop LEDU Leptochloa dubia 0–2 – fall witchgrass DICO6 Digitaria cognata 0–2 – nineawn pappusgrass ENDE Enneapogon desvauxii 0–2 – squirreltail ELELE Elymus elymoides ssp. elymoides 0–1 – 4 Annual grasses 1–355 Mexican panicgrass PAHI5 Panicum hirticaule 0–100 – sixweeks threeawn ARAD Aristida adscensionis 1–100 – mucronate sprangeltop LEPAB Leptochloa panicea ssp. brachiata 0–50 – sixweeks fescue VUOC Vulpia octoflora 1–50 – prairie threeawn AROL Aristida oligantha 0–25 – sixweeks grama BOBA2 Bouteloua barbata 0–25 – Rothrock's grama BORO2 Bouteloua rothrockii 0–20 – Bigelow's bluegrass POBI Poa bigelovii 0–20 – Eastwood fescue VUMIC Vulpia microstachys var. ciliata 0–15 – needle grama BOAR Bouteloua aristidoides 0–15 – delicate muhly MUFR Muhlenbergia fragilis 0–10 – littleseed muhly MUMI Muhlenbergia microsperma 0–10 – Pacific fescue VUMIP Vulpia microstachys var. pauciflora 0–10 – witchgrass PACA6 Panicum capillare 0–5 – Mexican sprangletop LEFUU Leptochloa fusca ssp. uninervia 0–5 – Arizona brome BRAR4 Bromus arizonicus 0–2 – feather fingergrass CHVI4 Chloris virgata 0–2 – tapertip cupgrass ERACA Eriochloa acuminata var. acuminata 0–2 – bearded cupgrass ERAR5 Eriochloa aristata 0–2 – desert lovegrass ERPEM Eragrostis pectinacea var. miserrima 0–2 – tufted lovegrass ERPEP2 Eragrostis pectinacea var. pectinacea 0–2 – Grisebach's bristlegrass SEGR6 Setaria grisebachii 0–2 – Arizona signalgrass URAR Urochloa arizonica 0–2 – Forb5 Ferns and fern allies 10–110 Arizona spikemoss SEAR2 Selaginella arizonica 10–100 – lipfern CHEIL Cheilanthes 1–5 – cliffbrake PELLA Pellaea 0–5 – cloak fern NOTHO Notholaena 0–1 – 6 Perennial forbs 10–60 slender janusia JAGR Janusia gracilis 5–40 – desert globemallow SPAM2 Sphaeralcea ambigua 5–20 – shrubby deervetch LORI3 Lotus rigidus 0–10 – rough menodora MESC Menodora scabra 0–10 – slender poreleaf POGR5 Porophyllum gracile 0–10 – wishbone-bush MILAV Mirabilis laevis var. villosa 0–5 – Parry's false prairie-clover MAPA7 Marina parryi 0–5 – brownfoot ACWR5 Acourtia wrightii 0–5 – weakleaf bur ragweed AMCO3 Ambrosia confertiflora 1–5 – narrowleaf silverbush ARLA12 Argythamnia lanceolata 0–5 – Arizona wrightwort CAAR7 Carlowrightia arizonica 0–5 – desert rosemallow HICO Hibiscus coulteri 0–2 – San Felipe dogweed ADPO Adenophyllum porophylloides 0–2 – 7 Annual forbs and minor perennials 1–610 bristly fiddleneck AMTE3 Amsinckia tessellata 0–100 – California poppy ESCAM Eschscholzia californica ssp. mexicana 0–100 – Coulter's lupine LUSP2 Lupinus sparsiflorus 0–100 – goosefoot CHENO Chenopodium 0–50 – cryptantha CRYPT Cryptantha 0–50 – western tansymustard DEPI Descurainia pinnata 0–50 – desert Indianwheat PLOV Plantago ovata 0–50 – phacelia PHACE Phacelia 0–25 – milkvetch ASTRA Astragalus 0–25 – Coulter's spiderling BOCO2 Boerhavia coulteri 0–15 – coastal bird's-foot trefoil LOSA Lotus salsuginosus 0–15 – woolly tidestromia TILA2 Tidestromia lanuginosa 0–15 – thelypody THELY Thelypodium 0–10 – combseed PECTO Pectocarya 0–10 – coastal bird's-foot trefoil LOSAB Lotus salsuginosus var. brevivexillus 0–10 – American wild carrot DAPU3 Daucus pusillus 0–10 – miniature woollystar ERDI2 Eriastrum diffusum 0–10 – carelessweed AMPA Amaranthus palmeri 0–5 – shaggyfruit pepperweed LELA Lepidium lasiocarpum 0–5 – desert marigold BAMU Baileya multiradiata 0–5 – scarlet spiderling BOCO Boerhavia coccinea 0–5 – Tucson Mountain spiderling BOME Boerhavia megaptera 0–5 – New Mexico plumeseed RANE Rafinesquia neomexicana 0–5 – Coues' cassia SECO10 Senna covesii 0–5 – sleepy silene SIAN2 Silene antirrhina 0–5 – brownplume wirelettuce STPA4 Stephanomeria pauciflora 0–5 – bluedicks DICAC5 Dichelostemma capitatum ssp. capitatum 0–3 – Gordon's bladderpod LEGO Lesquerella gordonii 0–2 – lacy tansyaster MAPIP4 Machaeranthera pinnatifida ssp. pinnatifida var. pinnatifida 0–2 – bean PHASE Phaseolus 0–2 – orange fameflower PHAU13 Phemeranthus aurantiacus 0–2 – plains blackfoot MELE2 Melampodium leucanthum 0–2 – blazingstar MENTZ Mentzelia 0–2 – green carpetweed MOVE Mollugo verticillata 0–2 – bristly nama NAHI Nama hispidum 0–2 – desert tobacco NIOBO Nicotiana obtusifolia var. obtusifolia 0–2 – evening primrose OENOT Oenothera 0–2 – Florida pellitory PAFL3 Parietaria floridana 0–2 – spreading fleabane ERDI4 Erigeron divergens 0–2 – desert trumpet ERIN4 Eriogonum inflatum 0–2 – buckwheat ERIOG Eriogonum 0–2 – moleplant EULA4 Euphorbia lathyris 0–2 – wild dwarf morning-glory EVAR Evolvulus arizonicus 0–2 – California fagonbush FALA Fagonia laevis 0–2 – desert larkspur DEPA Delphinium parishii 0–2 – tall mountain larkspur DESC Delphinium scaposum 0–2 – bigseed alfalfa dodder CUIN Cuscuta indecora 0–2 – hairy prairie clover DAMO Dalea mollis 0–2 – hyssopleaf sandmat CHHY3 Chamaesyce hyssopifolia 0–2 – New Mexico thistle CINE Cirsium neomexicanum 0–2 – climbing wartclub BOSC Boerhavia scandens 0–2 – fringed redmaids CACI2 Calandrinia ciliata 0–2 – hoary bowlesia BOIN3 Bowlesia incana 0–2 – dense ayenia AYMI Ayenia microphylla 0–2 – white sagebrush ARLU Artemisia ludoviciana 0–2 – New Mexico silverbush ARNE2 Argythamnia neomexicana 0–2 – jewels of Opar TAPA2 Talinum paniculatum 0–2 – woollyhead neststraw STMI2 Stylocline micropoides 0–2 – branched noseburn TRRA5 Tragia ramosa 0–2 – Lemmon's ragwort SELE8 Senecio lemmonii 0–2 – spreading fanpetals SIAB Sida abutifolia 0–2 – Parry's beardtongue PEPA24 Penstemon parryi 0–2 – chia SACO6 Salvia columbariae 0–1 – lyreleaf jewelflower STCA5 Streptanthus carinatus 0–1 – Louisiana vetch VILUL2 Vicia ludoviciana ssp. ludoviciana 0–1 – dwarf owl's-clover TRPU16 Triphysaria pusilla 0–1 – sand fringepod THCU Thysanocarpus curvipes 0–1 – perennial rockcress ARPE2 Arabis perennans 0–1 – tuber anemone ANTU Anemone tuberosa 0–1 – brittle spineflower CHBR Chorizanthe brevicornu 0–1 – Sonoran Indian mallow ABMO2 Abutilon mollicomum 0–1 – Palmer's Indian mallow ABPA Abutilon palmeri 0–1 – trailing windmills ALIN Allionia incarnata 0–1 – largeflower onion ALMA4 Allium macropetalum 0–1 – Davis Mountain mock vervain GLBIC Glandularia bipinnatifida var. ciliata 0–1 – Newberry's velvetmallow HONE Horsfordia newberryi 0–1 – Arizona popcornflower PLAR Plagiobothrys arizonicus 0–1 – whitestem blazingstar MEAL6 Mentzelia albicaulis 0–1 – Shrub/Vine8 Dominant small shrubs 75–300 triangle bur ragweed AMDE4 Ambrosia deltoidea 50–150 – broom snakeweed GUSA2 Gutierrezia sarothrae 5–50 – brittlebush ENFA Encelia farinosa 10–50 – Eastern Mojave buckwheat ERFA2 Eriogonum fasciculatum 1–40 – fairyduster CAER Calliandra eriophylla 5–40 – pelotazo ABIN Abutilon incanum 1–15 – Parish's goldeneye VIPA14 Viguiera parishii 1–15 – bastardsage ERWR Eriogonum wrightii 1–15 – 9 Miscellaneous shrubs 30–120 jojoba SICH Simmondsia chinensis 20–60 – littleleaf ratany KRER Krameria erecta 0–10 – white ratany KRGR Krameria grayi 0–10 – Berlandier's wolfberry LYBE Lycium berlandieri 2–10 – Arizona desert-thorn LYEX Lycium exsertum 1–5 – American threefold TRCA8 Trixis californica 0–5 – sangre de cristo JACA2 Jatropha cardiophylla 0–5 – water jacket LYAN Lycium andersonii 0–5 – catclaw acacia ACGR Acacia greggii 1–5 – Wright's beebrush ALWR Aloysia wrightii 0–5 – pelotazo ABIN Abutilon incanum 0–5 – Florida hopbush DOVI Dodonaea viscosa 0–4 – California copperleaf ACCA3 Acalypha californica 0–3 – whitethorn acacia ACCO2 Acacia constricta 0–2 – sweetbush BEJU Bebbia juncea 0–2 – Nevada jointfir EPNE Ephedra nevadensis 0–2 – rosary babybonnets COGL8 Coursetia glandulosa 0–2 – ragged rockflower CRBI2 Crossosoma bigelovii 0–2 – desert zinnia ZIAC Zinnia acerosa 0–2 – Arizona mimosa MIDIL Mimosa distachya var. laxiflora 0–2 – Schott's yellowhood NISC Nissolia schottii 0–2 – rock sage SAPI2 Salvia pinguifolia 0–2 – arrow poision plant SEBI9 Sebastiania bilocularis 0–2 – starry bedstraw GAST Galium stellatum 0–2 – creosote bush LATRT Larrea tridentata var. tridentata 0–1 – lotebush ZIOB Ziziphus obtusifolia 0–1 – Arizona rosewood VACA5 Vauquelinia californica 0–1 – Sonoran croton CRSO Croton sonorae 0–1 – Gray's prairie clover DAGR Dalea grayi 0–1 – knifeleaf condalia COSP3 Condalia spathulata 0–1 – cliff goldenbush ERCUC Ericameria cuneata var. cuneata 0–1 – turpentine bush ERLA12 Ericameria laricifolia 0–1 – Tahitian kidneywood EYOR Eysenhardtia orthocarpa 0–1 – desert olive FOSH Forestiera shrevei 0–1 – spiny hackberry CEEH Celtis ehrenbergiana 0–1 – desertbroom BASA2 Baccharis sarothroides 0–1 – prairie acacia ACANH Acacia angustissima var. hirta 0–1 – 10 Succulents 25–150 saguaro CAGI10 Carnegiea gigantea 10–100 – cactus apple OPEN3 Opuntia engelmannii 10–30 – jumping cholla CYFU10 Cylindropuntia fulgida 0–20 – staghorn cholla CYVE3 Cylindropuntia versicolor 1–20 – Christmas cactus CYLE8 Cylindropuntia leptocaulis 0–10 – buck-horn cholla CYAC8 Cylindropuntia acanthocarpa 0–10 – teddybear cholla CYBI9 Cylindropuntia bigelovii 0–10 – tulip pricklypear OPPH Opuntia phaeacantha 1–10 – Santa Rita pricklypear OPSA Opuntia santa-rita 0–10 – organpipe cactus STTH3 Stenocereus thurberi 0–5 – banana yucca YUBA Yucca baccata 0–5 – candy barrelcactus FEWI Ferocactus wislizeni 1–5 – common sotol DAWH2 Dasylirion wheeleri 0–5 – dollarjoint pricklypear OPCH Opuntia chlorotica 0–2 – purple pricklypear OPMA8 Opuntia macrocentra 0–2 – Engelmann's hedgehog cactus ECEN Echinocereus engelmannii 0–1 – pinkflower hedgehog cactus ECFA Echinocereus fasciculatus 0–1 – rainbow cactus ECPE Echinocereus pectinatus 0–1 – spinystar ESVIV Escobaria vivipara var. vivipara 0–1 – globe cactus MAMMI Mammillaria 0–1 – soaptree yucca YUEL Yucca elata 0–1 – desert agave AGDE Agave deserti 0–1 – Schott's century plant AGSC3 Agave schottii 0–1 – Tree11 Dominant trees 55–200 yellow paloverde PAMI5 Parkinsonia microphylla 50–150 – desert ironwood OLTE Olneya tesota 5–50 – velvet mesquite PRVE Prosopis velutina 0–20 – Table 9. Community 2.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 10. Community 3.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 11. Community 4.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 12. Community 5.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 13. Community 6.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Interpretations
Animal community
Steep slopes and gravelly, cobbly surfaces hinder livestock distribution. This site is not well suited to grazing by cows in the hot season except in the areas where ridges trend north and south and western exposures are shady in the morning and eastern aspects in the afternoon. In such cases, distribution will be fairly good even in the summer. Stocker cattle are best adapted to use areas of this site. South facing slopes are used more in the winter due to warm temperatures and early spring greenup. North exposures, being shady and cooler, are used more in the fall due to a longer green season. The plant community has an excellent variety of browse and perennial grasses and forbs and will provide adequate nutrition throughout the year. Seep and canyon water may be available for short times in the winter and summer rainy seasons, but fractured bedrock makes this feature short-lived. Bluff and rimrock in Gneiss areas can form natural fencing with minimal actual fence construction.
Water developments are very important to wildlife species on this site. Cover, forage diversity, and topography are good enough for a great variety of wildlife including the larger desert mammals. In areas where the parent material is Gneiss, high percentages of bluff and rimrock outcrop make such areas favored by desert bighorn sheep. Desert tortoises den on very cobbly southern exposures in the winter time.Hydrological functions
This site is a fair producer of runoff due to steep slopes and shallow soils. Very gravelly and cobbly soil surfaces tend to hold water on the site.
Recreational uses
Hunting, hiking, birdwatching, photography, horseback riding, rock hounding, recreational mining
Wood products
Some paloverde, ironwood and mesquite for camp-fires and branding fires.
Other products
Stones and cobbles, decomposed granite, saguaro ribs, cholla skeletons. Tradtional foods like saguaro fruits, prickly pear tunas, cactus flower buds and jojoba nuts. Traditional herbs like coyote tobacco, mint bush, club moss, globe mallow and limberbush.
Supporting information
Inventory data references
Range 417s include 5 in excellent condition and 2 in good condition.
Type locality
Location 1: Pima County, AZ General legal description Sells Field Office - North Comobabi Mtns. (unsurveyed) 32 8' long. X 111 47' latitude Brownell Mtns. (unsurveyed) 32 11' long. X 112 7' latitude Location 2: Pima County, AZ General legal description Sells Field Office - Sierra Blanca Mtns. 32 11' X 112 14' Quijotoa Mnts. 32 7' X 112 10' Location 3: Pima County, AZ Township/Range/Section T8S R13E S29 General legal description Tucson Field Office - Rancho Nuevo - Antelope Peak Location 4: Gila County, AZ Township/Range/Section T4S R17E S5 General legal description San Carlos Field Office - Mineral Strip, Granite Basin Contributors
C.Michaels
Dan Robinett
Larry D. EllicottRangeland 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) Dave Womack, Dan Robinett, Emilio Carrillo Contact for lead author NRCS Tucson Area Office Date 03/08/2005 Approved by Approval date Composition (Indicators 10 and 12) based on Annual Production Indicators
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Number and extent of rills:
Follow faults and bedding planes in parent material. -
Presence of water flow patterns:
Discontinuous, 10-15 feet in length. Will see shorter flow paths with high surface coarse fragments. -
Number and height of erosional pedestals or terracettes:
No accumulated or erosional pedestals. -
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
1-15% (low values due to high rock and gravel cover) -
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):
Most litter size classes stay in place due to high rock and gravel cover. -
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Expect ratings of 1-3 in perennial plant interspaces, 4-5 under shrub canopies. -
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
Weak thin platy to weak granular; color is 7.5-10YR5/4 dry, 7.5-10YR4/4 moist; thickness to 2 nches. -
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Canopy 15-20%; 50% shrubs, 10-15% subshrubs, 5-10% trees, 5-10% succulents, 5-10@ forbs and 2-% perennial grasses. Cover is well dispersed throughout the site. -
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:
shrubs > subshrubs > trees > succulents > annual forbs & grasses > perennial forbs > perennial grassesSub-dominant:
Other:
Additional:
-
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
20-50% tree & shrub canopy mortlity, 75-90% mortality of perennial grasses. -
Average percent litter cover (%) and depth ( in):
-
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
219 lbs/ac unfavorable precipitation, 790 lbs/ac normal precipitation, 1800 lbs/ac favorable precipitation -
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:
triangle brsage, littleleaf palverde, wite brittlebush, cholla, bufflegrass, fountain grass -
Perennial plant reproductive capability:
Not impaired for shrubs; drought impaired for perennial grasses and forbs.
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