Natural Resources
Conservation Service
-
Search
Major Land Resource Area or ecological site by name and/or ID.
PreviousSectionsNextGeneral 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.
Click to explore map
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
R040XA105AZ Shallow Hills 10"-13" p.z.
R040XA123AZ Volcanic Hills 10"-13" P.Z.
Similar sites
R041XC322AZ Shallow Upland 12-16" p.z.
R040XB220AZ Granitic Upland 7"-10" p.z.
Table 1. Dominant plant species
Tree (1) Parkinsonia microphylla
(2) Carnegia giganteaShrub (1) Calliandra eriophylla
Herbaceous (1) Janusia gracilis
(2) Aristida purpureaPhysiographic features
This site occurs in the upper elevations of the Sonoran Desert in southern Arizona. This site occurs on gently sloping to moderately steep pediments, flanking mountain areas. Numerous small areas of rock outcrop occur throughout areas of this site.
Table 2. Representative physiographic features
Landforms (1) Pediment
Flooding frequency None Ponding frequency None Elevation 2000 – 3300 ft Slope 1 – 15 % Aspect Aspect is not a significant factor 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 soils have developed in place on granitic and rhyolitic types of parent material. They are shallow, non-calcareous and the underlying bedrock is fractured and weathered. Soil surfaces are well covered by small gravels. Plant-soil moisture relationships range from fair to poor for shallow and very shallow soils respectively.
Soils mapped on this site include:
SSA-645 Aguila-Carefree area MU's Gran-61 & Wickenburg-61;
SSA-661 Eastern Pinal-Southern Gila Counties MU Anklam-240;
SSA-669 Eastern Pima County MU's Lehmans-13, Chimenea-16 & Granolite-58;
SSA-703 Tohono O'odham area MU's Anklam-3 & Granolite-48.Table 4. Representative soil features
Parent material (1) Residuum – granite
Surface texture (1) Very gravelly sandy loam
(2) Gravelly sandy loam
(3) Cobbly sandy loam
Family particle size (1) Loamy
Drainage class Well drained Permeability class Moderately rapid to moderately slow Soil depth 5 – 20 in Surface fragment cover <=3" 35 – 70 % 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
Figure 4. State and Transition model, Granitic Upland 10-13"
More interactive model formats are also available. View Interactive Models
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 on the site is a diverse mixture of desert shrubs, cacti, trees and perennial grasses and forbs. Annuals are of minor importance on the site. All of the major shrub and perennial grass and forb species on the site tend to be well dispersed throughout the plant community. The aspect is shrubland.
With continuous, heavy grazing, forage species like bush muhly, false mesquite, desert zinnia, janusia, and range ratany are removed from the plant community and replaced by increases in shrubs like triangle bursage, turpentine bush, snakeweed and cacti. Trees tend to be shrubby on this site due to shallow soils. This site generally lacks the cobble and stone cover of adjacent hillsites. Gravel size and cover may be inadequate on moderate slopes in preventing water erosion.
Saguaro can usually be found on this site in many age classes due to numerous rocky areas offering good seedling habitat in most years.
Stands of mature saguaro will result in fewer trees on the site and vice versa.
Figure 5. 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)Grass/Grasslike 6 60 240 Shrub/Vine 46 160 220 Tree 60 120 160 Forb 10 60 160 Total 122 400 780 Table 6. Soil surface cover
Tree basal cover 0-0% Shrub/vine/liana basal cover 0-0% Grass/grasslike basal cover 0-0% Forb basal cover 0-0% Non-vascular plants 0% Biological crusts 0-10% Litter 10-30% Surface fragments >0.25" and <=3" 40-70% Surface fragments >3" 10-20% Bedrock 0-10% Water 0% Bare ground 10-60% Table 7. Canopy structure (% cover)
Height Above Ground (ft) Tree Shrub/Vine Grass/
GrasslikeForb <0.5 – 0-1% 0-15% 0-10% >0.5 <= 1 – 1-5% 1-5% 1-5% >1 <= 2 – 2-10% 0-2% 0-5% >2 <= 4.5 – 0-2% – – >4.5 <= 13 0-1% – – – >13 <= 40 1-10% – – – >40 <= 80 – – – – >80 <= 120 – – – – >120 – – – – 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 fireCommunity 2.1
Native trees, shrubs, cacti 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. Annual grasses and forbs dominate the community for some time until perennial grasses, forbs and shrubs can recover.
This plant community can produce enough herbaceous fuel from native species of grasses and / or forbs to carry fire only in unusually wet winter or 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, ayenia and deer weed.
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, schismus and / or filaree. These species occupy the niche of the native winter annual forbs and grasses. These exotic annual grasses 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, schismus or filaree has burned repeatedly. As fires become more frequent the native trees, shrubs and succulents are removed from the plant community and these species become 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 5–80 purple threeawn ARPU9 Aristida purpurea 1–40 – tanglehead HECO10 Heteropogon contortus 1–40 – bush muhly MUPO2 Muhlenbergia porteri 1–40 – slim tridens TRMU Tridens muticus 1–30 – Parish's threeawn ARPUP5 Aristida purpurea var. parishii 0–20 – spidergrass ARTE3 Aristida ternipes 1–20 – spidergrass ARTEG Aristida ternipes var. gentilis 0–10 – Santa Rita threeawn ARCAG Aristida californica var. glabrata 0–10 – 2 Misc perennial grasses 1–20 red grama BOTR2 Bouteloua trifida 0–10 – blue threeawn ARPUN Aristida purpurea var. nealleyi 0–5 – sideoats grama BOCU Bouteloua curtipendula 0–5 – black grama BOER4 Bouteloua eriopoda 0–5 – cane bluestem BOBA3 Bothriochloa barbinodis 0–2 – low woollygrass DAPU7 Dasyochloa pulchella 0–2 – Arizona cottontop DICA8 Digitaria californica 0–2 – tobosagrass PLMU3 Pleuraphis mutica 0–2 – big galleta PLRI3 Pleuraphis rigida 0–2 – sand dropseed SPCR Sporobolus cryptandrus 0–2 – Havard's threeawn ARHA3 Aristida havardii 0–2 – Fendler threeawn ARPUL Aristida purpurea var. longiseta 0–1 – desert needlegrass ACSP12 Achnatherum speciosum 0–1 – plains bristlegrass SEVU2 Setaria vulpiseta 0–1 – spike dropseed SPCO4 Sporobolus contractus 0–1 – 3 Dominant short grasses 0–40 slender grama BORE2 Bouteloua repens 0–20 – curly-mesquite HIBE Hilaria belangeri 0–20 – Rothrock's grama BORO2 Bouteloua rothrockii 0–15 – 4 Annual grasses 0–100 sixweeks threeawn ARAD Aristida adscensionis 0–100 – mucronate sprangeltop LEPAB Leptochloa panicea ssp. brachiata 0–20 – sixweeks fescue VUOC Vulpia octoflora 0–20 – Mexican panicgrass PAHI5 Panicum hirticaule 0–10 – needle grama BOAR Bouteloua aristidoides 0–10 – sixweeks grama BOBA2 Bouteloua barbata 0–10 – prairie threeawn AROL Aristida oligantha 0–5 – delicate muhly MUFR Muhlenbergia fragilis 0–2 – littleseed muhly MUMI Muhlenbergia microsperma 0–2 – Bigelow's bluegrass POBI Poa bigelovii 0–2 – desert lovegrass ERPEM Eragrostis pectinacea var. miserrima 0–2 – Arizona brome BRAR4 Bromus arizonicus 0–1 – Forb5 Perennial forbs 10–60 slender janusia JAGR Janusia gracilis 2–20 – shrubby deervetch LORI3 Lotus rigidus 1–15 – desert globemallow SPAM2 Sphaeralcea ambigua 2–15 – brownplume wirelettuce STPA4 Stephanomeria pauciflora 0–10 – lacy tansyaster MAPIP4 Machaeranthera pinnatifida ssp. pinnatifida var. pinnatifida 1–10 – wishbone-bush MILAV Mirabilis laevis var. villosa 0–10 – desert marigold BAMU Baileya multiradiata 0–10 – Arizona wrightwort CAAR7 Carlowrightia arizonica 0–5 – red-gland spurge CHME5 Chamaesyce melanadenia 1–5 – San Felipe dogweed ADPO Adenophyllum porophylloides 0–5 – bluedicks DICA14 Dichelostemma capitatum 0–5 – Parry's false prairie-clover MAPA7 Marina parryi 0–5 – desert trumpet ERIN4 Eriogonum inflatum 1–5 – dense ayenia AYMI Ayenia microphylla 0–5 – Parry's beardtongue PEPA24 Penstemon parryi 0–2 – glandleaf milkwort POMA7 Polygala macradenia 0–2 – spearleaf MAPA9 Matelea parvifolia 0–2 – weakleaf bur ragweed AMCO3 Ambrosia confertiflora 0–2 – tuber anemone ANTU Anemone tuberosa 0–1 – narrowleaf silverbush ARLA12 Argythamnia lanceolata 0–1 – New Mexico silverbush ARNE2 Argythamnia neomexicana 0–1 – Braun's rockcress ARPE3 Arabis perstellata 0–1 – trailing windmills ALIN Allionia incarnata 0–1 – dwarf desertpeony ACNA2 Acourtia nana 0–1 – brownfoot ACWR5 Acourtia wrightii 0–1 – hairy five eyes CHSO Chamaesaracha sordida 0–1 – Parish's larkspur DEPAP3 Delphinium parishii ssp. parishii 0–1 – tall mountain larkspur DESC Delphinium scaposum 0–1 – desert mariposa lily CAKE Calochortus kennedyi 0–1 – lipfern CHEIL Cheilanthes 0–1 – scarlet spiderling BOCO Boerhavia coccinea 0–1 – wild dwarf morning-glory EVAR Evolvulus arizonicus 0–1 – California fagonbush FALA Fagonia laevis 0–1 – desert rosemallow HICO Hibiscus coulteri 0–1 – paleface HIDE Hibiscus denudatus 0–1 – spreading fleabane ERDI4 Erigeron divergens 0–1 – plains blackfoot MELE2 Melampodium leucanthum 0–1 – desert tobacco NIOBO Nicotiana obtusifolia var. obtusifolia 0–1 – cloak fern NOTHO Notholaena 0–1 – cliffbrake PELLA Pellaea 0–1 – Arizona spikemoss SEAR2 Selaginella arizonica 0–1 – spreading fanpetals SIAB Sida abutifolia 0–1 – slender poreleaf POGR5 Porophyllum gracile 0–1 – 6 Annual forbs 0–100 California poppy ESCAM Eschscholzia californica ssp. mexicana 0–20 – coastal bird's-foot trefoil LOSAB Lotus salsuginosus var. brevivexillus 0–20 – desert Indianwheat PLOV Plantago ovata 0–20 – Coulter's lupine LUSP2 Lupinus sparsiflorus 0–15 – exserted Indian paintbrush CAEXE Castilleja exserta ssp. exserta 0–15 – smallflowered milkvetch ASNU4 Astragalus nuttallianus 0–10 – Coulter's spiderling BOCO2 Boerhavia coulteri 0–10 – common fiddleneck AMMEI2 Amsinckia menziesii var. intermedia 0–10 – Sonoran sandmat CHMI7 Chamaesyce micromera 0–10 – cryptantha CRYPT Cryptantha 0–10 – western tansymustard DEPI Descurainia pinnata 0–10 – miniature woollystar ERDI2 Eriastrum diffusum 0–10 – woolly plantain PLPA2 Plantago patagonica 0–10 – combseed PECTO Pectocarya 0–10 – foothill deervetch LOHU2 Lotus humistratus 0–10 – distant phacelia PHDI Phacelia distans 0–10 – thelypody THELY Thelypodium 0–10 – woolly tidestromia TILA2 Tidestromia lanuginosa 0–10 – American wild carrot DAPU3 Daucus pusillus 0–5 – Gordon's bladderpod LEGO Lesquerella gordonii 0–5 – shaggyfruit pepperweed LELA Lepidium lasiocarpum 0–3 – flatcrown buckwheat ERDE6 Eriogonum deflexum 0–2 – Florida pellitory PAFL3 Parietaria floridana 0–2 – glandular threadplant NEGL Nemacladus glanduliferus 0–2 – Arizona phacelia PHAR13 Phacelia arizonica 0–2 – cleftleaf wildheliotrope PHCR Phacelia crenulata 0–2 – chia SACO6 Salvia columbariae 0–2 – sleepy silene SIAN2 Silene antirrhina 0–2 – star gilia GIST Gilia stellata 0–2 – woollyhead neststraw STMI2 Stylocline micropoides 0–2 – buckwheat ERIOG Eriogonum 0–2 – hairy prairie clover DAMO Dalea mollis 0–2 – devil's spineflower CHRI Chorizanthe rigida 0–2 – Esteve's pincushion CHST Chaenactis stevioides 0–2 – New Mexico thistle CINE Cirsium neomexicanum 0–2 – pincushion flower CHFR Chaenactis fremontii 0–2 – carelessweed AMPA Amaranthus palmeri 0–2 – bristly fiddleneck AMTE3 Amsinckia tessellata 0–2 – white easterbonnets ANLA7 Antheropeas lanosum 0–2 – hoary bowlesia BOIN3 Bowlesia incana 0–2 – yellow tackstem CAPA7 Calycoseris parryi 0–2 – white tackstem CAWR Calycoseris wrightii 0–2 – pitseed goosefoot CHBE4 Chenopodium berlandieri 0–2 – brittle spineflower CHBR Chorizanthe brevicornu 0–2 – Chiricahua Mountain sandmat CHFL3 Chamaesyce florida 0–1 – California suncup CACA32 Camissonia californica 0–1 – fringed amaranth AMFI Amaranthus fimbriatus 0–1 – sand pygmyweed CRCOC Crassula connata var. connata 0–1 – wedgeleaf draba DRCU Draba cuneifolia 0–1 – Abert's buckwheat ERAB2 Eriogonum abertianum 0–1 – sorrel buckwheat ERPO4 Eriogonum polycladon 0–1 – Texas stork's bill ERTE13 Erodium texanum 0–1 – sand fringepod THCU Thysanocarpus curvipes 0–1 – Louisiana vetch VILU Vicia ludoviciana 0–1 – Palmer's grapplinghook HAPA7 Harpagonella palmeri 0–1 – California goldfields LACAC2 Lasthenia californica ssp. californica 0–1 – flatspine stickseed LAOCO Lappula occidentalis var. occidentalis 0–1 – Mexican fireplant EUHE4 Euphorbia heterophylla 0–1 – spring pygmycudweed EVVE Evax verna 0–1 – limestone bedstraw GAPR Galium proliferum 0–1 – California desertdandelion MACA6 Malacothrix californica 0–1 – slender goldenweed MAGR10 Machaeranthera gracilis 0–1 – mesa tansyaster MATA Machaeranthera tagetina 0–1 – whitestem blazingstar MEAL6 Mentzelia albicaulis 0–1 – Lindley's silverpuffs MILI5 Microseris lindleyi 0–1 – Mojave desertstar MOBE2 Monoptilon bellioides 0–1 – lyreleaf jewelflower STCAA Streptanthus carinatus ssp. arizonicus 0–1 – manybristle chinchweed PEPA2 Pectis papposa 0–1 – desert evening primrose OEPR Oenothera primiveris 0–1 – Arizona cottonrose LOAR12 Logfia arizonica 0–1 – Shrub/Vine8 Dominant low shrubs 20–60 fairyduster CAER Calliandra eriophylla 5–25 – Eastern Mojave buckwheat ERFA2 Eriogonum fasciculatum 0–15 – bastardsage ERWR Eriogonum wrightii 0–10 – triangle bur ragweed AMDE4 Ambrosia deltoidea 1–10 – Coulter's brickellbush BRCO Brickellia coulteri 1–10 – littleleaf ratany KRER Krameria erecta 1–10 – white ratany KRGR Krameria grayi 0–10 – desert zinnia ZIAC Zinnia acerosa 1–10 – rough menodora MESC Menodora scabra 0–5 – brittlebush ENFA Encelia farinosa 0–5 – Palmer's Indian mallow ABPA Abutilon palmeri 0–5 – broom snakeweed GUSA2 Gutierrezia sarothrae 0–5 – American threefold TRCA8 Trixis californica 0–2 – 9 Dominant large shrubs 15–80 jojoba SICH Simmondsia chinensis 5–25 – ocotillo FOSP2 Fouquieria splendens 5–20 – sangre de cristo JACA2 Jatropha cardiophylla 0–15 – pelotazo ABIN Abutilon incanum 0–15 – whitethorn acacia ACCO2 Acacia constricta 0–10 – desert lavender HYEM Hyptis emoryi 0–10 – Berlandier's wolfberry LYBE Lycium berlandieri 1–5 – 10 Miscellaneous shrubs 1–10 Wright's beebrush ALWR Aloysia wrightii 0–3 – Tucson bur ragweed AMCO4 Ambrosia cordifolia 0–2 – burrobush AMDU2 Ambrosia dumosa 0–2 – Warnock's snakewood COWA Condalia warnockii 0–2 – sweetbush BEJU Bebbia juncea 0–2 – creosote bush LATRT Larrea tridentata var. tridentata 0–2 – water jacket LYAN Lycium andersonii 0–1 – Arizona desert-thorn LYEX Lycium exsertum 0–1 – Arizona mimosa MIDIL Mimosa distachya var. laxiflora 0–1 – whitestem paperflower PSCO2 Psilostrophe cooperi 0–1 – toothleaf goldeneye VIDE3 Viguiera dentata 0–1 – banana yucca YUBA Yucca baccata 0–1 – lotebush ZIOB Ziziphus obtusifolia 0–1 – spiny hackberry CEEH Celtis ehrenbergiana 0–1 – rosary babybonnets COGL8 Coursetia glandulosa 0–1 – Nevada jointfir EPNE Ephedra nevadensis 0–1 – longleaf jointfir EPTR Ephedra trifurca 0–1 – turpentine bush ERLA12 Ericameria laricifolia 0–1 – burrobrush HYSA Hymenoclea salsola 0–1 – burroweed ISTE2 Isocoma tenuisecta 0–1 – fourwing saltbush ATCA2 Atriplex canescens 0–1 – prairie acacia ACANH Acacia angustissima var. hirta 0–1 – rayless goldenhead ACSP Acamptopappus sphaerocephalus 0–1 – 11 Succulents 10–80 saguaro CAGI10 Carnegiea gigantea 5–50 – walkingstick cactus CYSP8 Cylindropuntia spinosior 0–10 – staghorn cholla CYVE3 Cylindropuntia versicolor 1–10 – cactus apple OPEN3 Opuntia engelmannii 1–10 – purple pricklypear OPMA8 Opuntia macrocentra 0–10 – tulip pricklypear OPPH Opuntia phaeacantha 0–10 – candy barrelcactus FEWI Ferocactus wislizeni 1–5 – Christmas cactus CYLE8 Cylindropuntia leptocaulis 1–5 – teddybear cholla CYBI9 Cylindropuntia bigelovii 0–5 – jumping cholla CYFU10 Cylindropuntia fulgida 0–5 – pinkflower hedgehog cactus ECFA Echinocereus fasciculatus 1–5 – buck-horn cholla CYAC8 Cylindropuntia acanthocarpa 0–5 – Arizona pencil cholla CYAR14 Cylindropuntia arbuscula 0–2 – Schott's century plant AGSC3 Agave schottii 0–2 – Graham's nipple cactus MAGR9 Mammillaria grahamii 1–2 – Thornber's nipple cactus MATH Mammillaria thornberi 0–1 – soaptree yucca YUEL Yucca elata 0–1 – rainbow cactus ECPE Echinocereus pectinatus 0–1 – spinystar ESVIV Escobaria vivipara var. vivipara 0–1 – candle cholla CYKL Cylindropuntia kleiniae 0–1 – Engelmann's hedgehog cactus ECEN Echinocereus engelmannii 0–1 – redspine fishhook cactus ECER2 Echinomastus erectocentrus 0–1 – long-tubercle beehive cactus COROR Coryphantha robustispina ssp. robustispina 0–1 – desert agave AGDE Agave deserti 0–1 – Tree12 Trees 60–160 yellow paloverde PAMI5 Parkinsonia microphylla 60–120 – desert ironwood OLTE Olneya tesota 0–80 – velvet mesquite PRVE Prosopis velutina 0–25 – catclaw acacia ACGR Acacia greggii 0–15 – 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
This site produces very little herbaceous forage for livestock. The plant community has a good variety of evergreen browse species making it suitable for winter grazing. Areas of this site are associated with steep rough hillsites and will be over used unless grazing systems allow enough rest for recovery or unless fencing is used to isolate the site from the hillsites. Water may be available in the bedrock canyons bisecting the site in both the winter and summer.
The site provides good habitat for a variety of desert wildlife including the larger mammals. Water developments are very important to wildlife on this site.
Although free water may be found in rocky drainages in the rainy seasons, water developments would help ensure year-round use of the site by the large desert mammals. Cover, forage plant diversity and topography are good enough for a great variety of wildlife.Hydrological functions
This site is a fair to good producer of runoff due to moderate slopes and shallow to very shallow soils. Very gravelly soil surfaces help 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
Type locality
Location 1: Pima County, AZ Township/Range/Section T14S R16E S28 General legal description Tucson FO - Saguaro Nat'l. Monument East Location 2: Pima County, AZ General legal description Sells FO - Quijotoa Mountains 112 7' X 32 11' (unsurveyed) Location 3: Pima County, AZ Township/Range/Section T15S R9E S9 General legal description La Tortuga Ranch, in the Tortuga pasture 2 miles south of Turtle well. Ungrazed 15 years. Contributors
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
-
Number and extent of rills:
Rills are present on this site but follow joints, bedding planes, and fractures in the bedrock parent materials. -
Presence of water flow patterns:
Discontinuous, 10-15 feet in length. -
Number and height of erosional pedestals or terracettes:
No pedestals on plants, rock or gravel fragments and no terracettes are present. -
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
10-60% (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. Herbaceous litter moves 10-15 feet in flow paths. -
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 granular; color is 7.5-10YR5/4 dry, 7.5-10YR4/4 moist; thickness to 2 inches. -
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Canopy 15-20%; 50-65% shrbs, 15-20 trees,5-10% succulents, 2-5% perennial grasses. Cove is well dispersed throughout 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:
sub shrubs > trees > winter annuals > shrubs > perennial forbs > perennial grasses > summer annuals > succulentsSub-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 mortality; 75-90% perennial grass mortality -
Average percent litter cover (%) and depth ( in):
-
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
122 lbs/ac unfavorable precipitation; 400 lbs/ac normal precipitation; 780 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 bursage, turpentine bush, snakeweed, cacti, bufflegrass -
Perennial plant reproductive capability:
Not impaired for shrubs, drought impaired for perennial grasses and forbs.
Print Options
Sections
Font
AAAAOther
PrintThe Ecosystem Dynamics Interpretive Tool is an information system framework developed by the USDA-ARS Jornada Experimental Range, USDA Natural Resources Conservation Service, and New Mexico State University.
Accessibility statement
