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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.Associated sites
R040XA104AZ Clayey Upland 10"-13" p.z.
R040XA108AZ Limy Fan 10"-13" p.z.
R040XA112AZ Loamy Swale 10"-13" p.z.
Similar sites
R040XB203AZ Clayey Swale 7"-10" p.z.
R041XC302AZ Clayey Swale 12-16" p.z.
R041XB202AZ Clayey Swale 8-12" p.z.
Table 1. Dominant plant species
Tree Not specified
Shrub (1) Opuntia chlorotica
Herbaceous (1) Pleuraphis mutica
(2) Panicum obtusumPhysiographic features
This site occurs in the upper elevations of the Sonoran Desert in southern Arizona. This site receives extra moisture in the form of runoff from adjacent upland areas. It occurs on floodplains, alluvial fans and swales.
Table 2. Representative physiographic features
Landforms (1) Alluvial fan
(2) Flood plain
(3) Swale
Flooding duration Extremely brief (0.1 to 4 hours) to very brief (4 to 48 hours) Flooding frequency Rare to occasional Ponding duration Very brief (4 to 48 hours) to brief (2 to 7 days) Ponding frequency None to rare Elevation 1900 – 3300 ft Slope 0 – 2 % 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 are deep soils on clayey, recent alluvium of mixed origins. They are dark colored and have high shrink-swell potentials. Churning and cracking cause very rough surfaces. Plant-soil moisture relationships are good. The soils mapped on this site are: SSA-645 Aguila-Carefree MU's Guest-67 & 88; SSA-669 Eastern Pima County Hantz-34; SSA-703 Tohono O'odham MU's Tubac-6 & Hantz-34.
Table 4. Representative soil features
Surface texture (1) Clay loam
(2) Silty clay loam
(3) Clay
Family particle size (1) Clayey
Drainage class Well drained Permeability class Slow to very slow Soil depth 60 in Surface fragment cover <=3" 0 – 10 % Surface fragment cover >3" 0 – 1 % Available water capacity
(0-40in)9 – 10 in Calcium carbonate equivalent
(0-40in)0 – 10 % Electrical conductivity
(0-40in)0 – 4 mmhos/cm Sodium adsorption ratio
(0-40in)0 – 13 Soil reaction (1:1 water)
(0-40in)7.2 – 8.2 Subsurface fragment volume <=3"
(Depth not specified)0 – 5 % Subsurface fragment volume >3"
(Depth not specified)Not specified 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, Clayey swale 10-13" pz.
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 this site is dominated by tobosa grass. A few shrubby species like soaptree yucca and prickley pear dot this open grassland site.
With continuous, heavy grazing, the tobosa cover is depleted in patches. This site is extremely susceptable to gully erosion when grass cover has been removed. Shrubby species like snakeweed, prickley pear, and mesquite can invade or increase to become dominant where gully formation drains water off rapidly and dries the site.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 815 1300 1850 Forb 10 100 460 Shrub/Vine 1 5 30 Tree 0 0 10 Total 826 1405 2350 Table 6. Soil surface cover
Tree basal cover 0% Shrub/vine/liana basal cover 0% Grass/grasslike basal cover 10-40% Forb basal cover 0-0% Non-vascular plants 0% Biological crusts 10-20% Litter 30-80% Surface fragments >0.25" and <=3" 0-10% Surface fragments >3" 0-0% Bedrock 0% Water 0% Bare ground 10-40% Table 7. Canopy structure (% cover)
Height Above Ground (ft) Tree Shrub/Vine Grass/
GrasslikeForb <0.5 – – 0-5% 0-5% >0.5 <= 1 – – 5-15% 1-5% >1 <= 2 – 0-1% 10-35% 0-15% >2 <= 4.5 – 0-1% 0-5% 0-1% >4.5 <= 13 0-1% – – – >13 <= 40 – – – – >40 <= 80 – – – – >80 <= 120 – – – – >120 – – – – Figure 6. Plant community growth curve (percent production by month). AZ4012 , 40.1 10-13" p.z. bottom sites. Growth begins in the late winter, most growth occurs in the summer..
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 2 8 10 10 10 15 20 15 5 5 0 State 2
Annuals and desert broomCommunity 2.1
Annuals and desert broomThis state occurs after clearing for irrigation and subsequent abandonment. Early stages of plant succession lead to dominance by annual forbs and grasses (both native and non-native). Tumbleweed (Russian thistle) will persist with continued disturbance like disking. Desert broom can invade and may dominate the upper layer of the plant community. This state will persist for several years before other shrubs and desert trees come in and assume dominance. It will persist for long periods of time with continued disturbance. Natural flooding is reduced or eliminated by dikes, ditches and levees that were built to protect irrigated fields.
State 3
Mesquite, grass and shrubsCommunity 3.1
Mesquite, grass and shrubsThis state will result from long term rest of areas that were cleared and then abandoned. Without disturbance for 30 or 40 years mesquite will come in with other shrubs like pencil cholla and whitethorn acacia and form an open overstory. Perennial grasses, both native and non-native will dominate the understory especially in areas where water accumulates; the bottom ends of fields and along borders and old ditches. Some areas (with heavy soil crusting due to silty clayloam textures) may be entirely barren until a wet winter is effective in producing a crop of annuals. Annual forbs and grasses (both native and exotic) will fluctuate with climate. This appears to be a stable community without fire or other disturbance like continuous grazing. Usually water control features (dikes, ditches) are left intact and natural flooding of these areas does not occur.
State 4
Exotic grasses and forbsCommunity 4.1
Exotic grasses and forbsNon-native perennial grasses like bermuda, Johnson grass, bufflegrass and exotic annuals like filaree, red brome, schismus, London rocket, Carolina canarygrass and purslane invade the native plant community. These species displace native perennial and annual grasses and forbs.
State 5
GulliedCommunity 5.1
GulliedThis state occurs where the site has severe sheet, rill and gully erosion. Lack of plant cover, soil compaction and concentration of surface water flow will lead to rilling and gully formation. Usually these areas lack any perennial cover except along drainage ways.
Base level changes in large stream systems can lead to gullying of this site where it is tributary to the main stream.State 6
Dense mesquiteCommunity 6.1
Dense mesquiteThis state occurs where large floods have breached the dikes and levees and filled the drainage ditches that used to protect the irrigated lands. Floods bring large amounts of mesquite seed, organic debris and water in and can cause a mesquite thicket to form. Usually the shrub density in these thickets is so high that they are impenetrable.
This state can also form on areas that have not been converted to cropland by continuous heavy grazing, depletion of grass cover, soil compaction and subsequent invasion and increase by mesquite.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 grass 800–1200 tobosagrass PLMU3 Pleuraphis mutica 800–1200 – 2 Misc perennial grasses 10–150 vine mesquite PAOB Panicum obtusum 5–100 – whiplash pappusgrass PAVA2 Pappophorum vaginatum 0–20 – bush muhly MUPO2 Muhlenbergia porteri 0–20 – burrograss SCBR2 Scleropogon brevifolius 0–10 – sideoats grama BOCU Bouteloua curtipendula 0–10 – plains bristlegrass SEVU2 Setaria vulpiseta 0–10 – Parish's threeawn ARPUP5 Aristida purpurea var. parishii 0–10 – spidergrass ARTE3 Aristida ternipes 0–10 – spidergrass ARTEG Aristida ternipes var. gentilis 0–10 – spike dropseed SPCO4 Sporobolus contractus 0–5 – Arizona cottontop DICA8 Digitaria californica 0–5 – large-spike bristlegrass SEMA5 Setaria macrostachya 0–5 – western wheatgrass PASM Pascopyrum smithii 0–5 – curly-mesquite HIBE Hilaria belangeri 0–4 – cane bluestem BOBA3 Bothriochloa barbinodis 0–3 – green sprangletop LEDU Leptochloa dubia 0–2 – 3 Annual grasses 5–500 mucronate sprangeltop LEPAB Leptochloa panicea ssp. brachiata 1–200 – little barley HOPU Hordeum pusillum 1–200 – sixweeks fescue VUOC Vulpia octoflora 0–150 – sticky sprangletop LEVI5 Leptochloa viscida 0–100 – Rothrock's grama BORO2 Bouteloua rothrockii 0–100 – sixweeks threeawn ARAD Aristida adscensionis 0–50 – feather fingergrass CHVI4 Chloris virgata 0–50 – Mexican panicgrass PAHI5 Panicum hirticaule 0–50 – canyon cupgrass ERLE7 Eriochloa lemmonii 0–25 – needle grama BOAR Bouteloua aristidoides 0–25 – sixweeks grama BOBA2 Bouteloua barbata 0–25 – Arizona signalgrass URAR Urochloa arizonica 0–25 – bearded cupgrass ERAR5 Eriochloa aristata 0–15 – Mexican sprangletop LEFUU Leptochloa fusca ssp. uninervia 0–10 – Bigelow's bluegrass POBI Poa bigelovii 0–5 – delicate muhly MUFR Muhlenbergia fragilis 0–5 – littleseed muhly MUMI Muhlenbergia microsperma 0–5 – Arizona brome BRAR4 Bromus arizonicus 0–5 – prairie threeawn AROL Aristida oligantha 0–5 – Eastwood fescue VUMIC Vulpia microstachys var. ciliata 0–3 – tufted lovegrass ERPEP2 Eragrostis pectinacea var. pectinacea 0–2 – Forb4 Perennial forbs 5–60 bluedicks DICAC5 Dichelostemma capitatum ssp. capitatum 1–20 – spear globemallow SPHA Sphaeralcea hastulata 1–20 – desert globemallow SPAM2 Sphaeralcea ambigua 0–10 – spreading fleabane ERDI4 Erigeron divergens 0–10 – Indian rushpea HOGL2 Hoffmannseggia glauca 1–10 – dwarf desertpeony ACNA2 Acourtia nana 0–5 – redseed plantain PLRH Plantago rhodosperma 0–5 – buffpetal RHPH2 Rhynchosida physocalyx 0–5 – spreading fanpetals SIAB Sida abutifolia 0–5 – silverleaf nightshade SOEL Solanum elaeagnifolium 0–2 – weakleaf bur ragweed AMCO3 Ambrosia confertiflora 0–2 – red-gland spurge CHME5 Chamaesyce melanadenia 0–2 – fingerleaf gourd CUDI Cucurbita digitata 0–2 – Missouri gourd CUFO Cucurbita foetidissima 0–2 – coyote gourd CUPA Cucurbita palmata 0–2 – pricklyburr DAIN2 Datura inoxia 0–1 – desert tobacco NIOBO Nicotiana obtusifolia var. obtusifolia 0–1 – orange fameflower PHAU13 Phemeranthus aurantiacus 0–1 – canaigre dock RUHY Rumex hymenosepalus 0–1 – brownplume wirelettuce STPA4 Stephanomeria pauciflora 0–1 – 5 Annual forbs 5–400 coastal bird's-foot trefoil LOSA Lotus salsuginosus 0–100 – Arizona popcornflower PLAR Plagiobothrys arizonicus 0–100 – foothill deervetch LOHU2 Lotus humistratus 0–50 – pitseed goosefoot CHBE4 Chenopodium berlandieri 0–50 – California poppy ESCAM Eschscholzia californica ssp. mexicana 0–50 – wheelscale saltbush ATEL Atriplex elegans 0–50 – smallflowered milkvetch ASNU4 Astragalus nuttallianus 0–25 – bristly fiddleneck AMTE3 Amsinckia tessellata 0–25 – fringed redmaids CACI2 Calandrinia ciliata 0–25 – Arizona poppy KAGR Kallstroemia grandiflora 0–25 – desert Indianwheat PLOV Plantago ovata 1–25 – woolly plantain PLPA2 Plantago patagonica 0–20 – Louisiana vetch VILU Vicia ludoviciana 0–20 – California desertdandelion MACA6 Malacothrix californica 0–20 – western tansymustard DEPI Descurainia pinnata 0–20 – carelessweed AMPA Amaranthus palmeri 0–20 – white easterbonnets ANLA7 Antheropeas lanosum 0–10 – fringed amaranth AMFI Amaranthus fimbriatus 0–10 – white tackstem CAWR Calycoseris wrightii 0–10 – miniature woollystar ERDI2 Eriastrum diffusum 0–10 – hyssopleaf sandmat CHHY3 Chamaesyce hyssopifolia 0–10 – Esteve's pincushion CHST Chaenactis stevioides 0–10 – cryptantha CRYPT Cryptantha 0–10 – hollowleaf annual lupine LUSU3 Lupinus succulentus 0–10 – mesa tansyaster MATA Machaeranthera tagetina 0–10 – Lindley's silverpuffs MILI5 Microseris lindleyi 0–10 – Texas stork's bill ERTE13 Erodium texanum 0–10 – distant phacelia PHDI Phacelia distans 0–10 – purslane PORTU Portulaca 0–10 – Nuttall's povertyweed MONU Monolepis nuttalliana 0–10 – Arizona phacelia PHAR13 Phacelia arizonica 0–10 – cleftleaf wildheliotrope PHCR Phacelia crenulata 0–5 – New Mexico plumeseed RANE Rafinesquia neomexicana 0–5 – Lemmon's ragwort SELE8 Senecio lemmonii 0–5 – Coulter's globemallow SPCO2 Sphaeralcea coulteri 0–5 – California mustard GULA4 Guillenia lasiophylla 0–5 – California goldfields LACAC2 Lasthenia californica ssp. californica 0–5 – flatspine stickseed LAOCO Lappula occidentalis var. occidentalis 0–5 – Gordon's bladderpod LEGO Lesquerella gordonii 0–5 – American wild carrot DAPU3 Daucus pusillus 0–5 – red-gland spurge CHME5 Chamaesyce melanadenia 0–5 – yellow tackstem CAPA7 Calycoseris parryi 0–5 – spreading fleabane ERDI4 Erigeron divergens 0–5 – wedgeleaf draba DRCU Draba cuneifolia 0–5 – California suncup CACA32 Camissonia californica 0–5 – New Mexico thistle CINE Cirsium neomexicanum 0–2 – star gilia GIST Gilia stellata 0–2 – sand fringepod THCU Thysanocarpus curvipes 0–2 – Fendler's horsenettle SOFE Solanum fendleri 0–1 – doubleclaw PRPA2 Proboscidea parviflora 0–1 – redseed plantain PLRH Plantago rhodosperma 0–1 – shaggyfruit pepperweed LELA Lepidium lasiocarpum 0–1 – Mojave desertstar MOBE2 Monoptilon bellioides 0–1 – tanseyleaf tansyaster MATA2 Machaeranthera tanacetifolia 0–1 – disc mayweed MADI6 Matricaria discoidea 0–1 – slender goldenweed MAGR10 Machaeranthera gracilis 0–1 – Palmer's spectaclepod DICA31 Dimorphocarpa candicans 0–1 – touristplant DIWI2 Dimorphocarpa wislizeni 0–1 – Mexican fireplant EUHE4 Euphorbia heterophylla 0–1 – hoary bowlesia BOIN3 Bowlesia incana 0–1 – common fiddleneck AMMEI2 Amsinckia menziesii var. intermedia 0–1 – desert tobacco NIOBO Nicotiana obtusifolia var. obtusifolia 0–1 – desert evening primrose OEPR Oenothera primiveris 0–1 – Florida pellitory PAFL3 Parietaria floridana 0–1 – manybristle chinchweed PEPA2 Pectis papposa 0–1 – Shrub/Vine6 Misc shrubs 0–10 fairyduster CAER Calliandra eriophylla 0–2 – spiny hackberry CEEH Celtis ehrenbergiana 0–2 – snakewood CONDA Condalia 0–2 – soaptree yucca YUEL Yucca elata 0–2 – lotebush ZIOB Ziziphus obtusifolia 0–1 – Nevada jointfir EPNE Ephedra nevadensis 0–1 – water jacket LYAN Lycium andersonii 0–1 – Berlandier's wolfberry LYBE Lycium berlandieri 0–1 – Arizona desert-thorn LYEX Lycium exsertum 0–1 – pale desert-thorn LYPA Lycium pallidum 0–1 – rough menodora MESC Menodora scabra 0–1 – whitethorn acacia ACCO2 Acacia constricta 0–1 – catclaw acacia ACGR Acacia greggii 0–1 – fourwing saltbush ATCA2 Atriplex canescens 0–1 – crucifixion thorn CAEM4 Castela emoryi 0–1 – 7 Succulents 1–20 walkingstick cactus CYSP8 Cylindropuntia spinosior 0–5 – dollarjoint pricklypear OPCH Opuntia chlorotica 0–5 – cactus apple OPEN3 Opuntia engelmannii 0–5 – staghorn cholla CYVE3 Cylindropuntia versicolor 0–1 – Engelmann's hedgehog cactus ECEN Echinocereus engelmannii 0–1 – candy barrelcactus FEWI Ferocactus wislizeni 0–1 – devil's cholla GRKU Grusonia kunzei 0–1 – buck-horn cholla CYAC8 Cylindropuntia acanthocarpa 0–1 – Arizona pencil cholla CYAR14 Cylindropuntia arbuscula 0–1 – jumping cholla CYFU10 Cylindropuntia fulgida 0–1 – Christmas cactus CYLE8 Cylindropuntia leptocaulis 0–1 – Tree8 Trees 0–10 velvet mesquite PRVE Prosopis velutina 0–10 – blue paloverde PAFL6 Parkinsonia florida 0–2 – yellow paloverde PAMI5 Parkinsonia microphylla 0–2 – 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
The plant community on this site is suitable for grazing by all classes of cattle. Tobosa grass is very unpalatable when cured and dormant and best use is made of this species in either spring or summer growing seasons. Prescribed burning or mowing can be used to freshen old growth tobosa grass. Burning should only be done in February or March and only in years with good enough winter rainfall for soils to have 3 inches of available moisture in the profile. Spring regrowth should then be rested until the first summer flood. The plant community will be deficient in digestible protein in the fall or winter.
This site is mainly a foraging area for large wildlife species. Free water is usually available in the summer rainy season in natural charcos and discontinuous gullies. Being open grassland, this site is home to a variety of small wildlife species and their predators.Hydrological functions
When dry, these soils produce little runoff due to cracks and depressions that hold water. When wet they produce good amounts of runoff due to heavy soil textures and swelling to seal cracks and holes.
Recreational uses
Hunting, hiking, horseback riding, photography, camping
Wood products
Little to nothing except in areas where mesquite has increased. In areas heavily invaded by mesquite good supplies of fuelwood are available.
Other products
Grass nuts, hog potatoes, prickly pear tunas and clay.
Supporting information
Inventory data references
Range 417s include 2 in fair condition.
Type locality
Location 1: Pima County, AZ Township/Range/Section T9S R2E S7 General legal description SELLS FIELD OFFICE - HICKIWAN DIST. HEADWATERS OF THE VEKOL VALLEY Location 2: Pima County, AZ Township/Range/Section T16S R15E S14 General legal description TUCSON FIELD OFFICE - PIMA COUNTY FAIRGROUNDS Contributors
C.Michaels
Dan Robinett
Larry D. Ellicott
M.G.LamerouxRangeland 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
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Number and extent of rills:
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Presence of water flow patterns:
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Number and height of erosional pedestals or terracettes:
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Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
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Number of gullies and erosion associated with gullies:
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Extent of wind scoured, blowouts and/or depositional areas:
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Amount of litter movement (describe size and distance expected to travel):
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Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
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Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
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Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
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Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
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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:
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Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
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Average percent litter cover (%) and depth ( in):
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Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
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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:
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Perennial plant reproductive capability:
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