Natural Resources
Conservation Service
Ecological site R041XB204AZ
Clay Loam Upland 8-12" p.z.
Last updated: 4/09/2021
Accessed: 01/10/2025
General information
Provisional. A provisional ecological site description has undergone quality control and quality assurance review. It contains a working state and transition model and enough information to identify the ecological site.
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): 041X–Madrean Archipelago
AZ 41.2 – Chihuahuan – Sonoran Desert Shrubs
Elevations range from 2600 to 4000 feet and precipitation ranges from 8 to 12 inches per year. Vegetation includes mesquite, palo verde, catclaw acacia, soaptree yucca, creosotebush, whitethorn, staghorn cholla, desert saltbush, Mormon tea, burroweed, snakeweed, tobosa, black grama, threeawns, bush muhly, dropseed, and burrograss. 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
| R041XB203AZ |
Clayey Upland 8-12" p.z. |
|---|---|
| R041XB210AZ |
Loamy Upland 8-12" p.z. |
Similar sites
| R041XC305AZ |
Clay Loam Upland 12-16" p.z. |
|---|---|
| R040XA120AZ |
Clay Loam Upland 10"-13" p.z. |
Table 1. Dominant plant species
| Tree |
Not specified |
|---|---|
| Shrub |
(1) Opuntia phaeacantha |
| Herbaceous |
(1) Pleuraphis mutica |
Physiographic features
This site occurs in the lowest elevations of the Madrean Basin and Range province in southeastern Arizona. It occurs on rolling low ridges, fan terraces, mesas and gently sloping uplands; generally below the hills and above the plains. The site is usually dissected by numerous water courses.
Table 2. Representative physiographic features
| Landforms |
(1)
Ridge
(2) Fan piedmont (3) Mesa |
|---|---|
| Flooding frequency | None |
| Ponding frequency | None |
| Elevation | 2,600 – 4,000 ft |
| Slope | 1 – 15% |
| Aspect | Aspect is not a significant factor |
Climatic features
Precipitation ranges from 8-12 inches annually. More than half falls during Jul-Sep in brief, but often heavy, thunderstorms. The rest of the moisture comes as light rain or snow that falls slowly for a day or more, but rarely lasts more than a day. May and June are normally the driest months. Humidity is generally very low.
Temperatures are mild throughout most of the year. Freezing temperatures are common at night Dec-Feb; brief 0 F may be observed some nights. During June, July & August, some days may exceed 100 F.
In years of average or greater winter precipitation, annual grasses and forbs occur abundantly in the interspaces.
Table 3. Representative climatic features
| Frost-free period (average) | 240 days |
|---|---|
| Freeze-free period (average) | |
| Precipitation total (average) |
Figure 2. Monthly precipitation range
Figure 3. Monthly average minimum and maximum temperature
Influencing water features
There are no water features associated with this site.
Soil features
These soils are moderately deep to deep and clayey textured. They have thin (1-2 inch) surface horizons that range from sandyloam to loam in texture. They lack vertic soil properties. They usually have well developed covers of surface gravels and cobbles. Surface soils (10 inches) are non-calcareous, but some soils have calcic horizons below the argillic horizon.
Soil series mapped on areas of this site include: SSA-663 Gila-Duncan area MU's 4 Artesia, 8 & 9 Continental, 16 Glendale, 40 Stellar, 41 Tapco and 43 Continental; SSA-664 San Simon area MU's 3 Artesia, 16 & 17 Eba, 22 & 23 Glendale, 41 Tubac and 45 Forrest; SSA-675 San Carlos IR area MU 93 Topawa.
Table 4. Representative soil features
| Surface texture |
(1) Very gravelly loam (2) Gravelly loam (3) Gravelly clay loam |
|---|---|
| Family particle size |
(1) Clayey |
| Drainage class | Well drained |
| Permeability class | Moderately slow to slow |
| Soil depth | 30 – 60 in |
| Surface fragment cover <=3" | 5 – 60% |
| Surface fragment cover >3" | 15% |
| Available water capacity (0-40in) |
4 – 9 in |
| Calcium carbonate equivalent (0-40in) |
15% |
| Electrical conductivity (0-40in) |
2 mmhos/cm |
| Sodium adsorption ratio (0-40in) |
2 |
| Soil reaction (1:1 water) (0-40in) |
7 – 8 |
| Subsurface fragment volume <=3" (Depth not specified) |
5 – 55% |
| Subsurface fragment volume >3" (Depth not specified) |
15% |
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 grazing, fire, 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 shown for the group. Divide the resulting total by the total normal year production shown in the plant community description. If 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
Figure 4. 41-2 Clay Loam Upland STM Diagram
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 text
Ecosystem states
State 1 submodel, plant communities
State 2 submodel, plant communities
State 3 submodel, plant communities
State 4 submodel, plant communities
State 1
Reference
Community 1.1
Desert grass-shrubland (HCPC)
Figure 5. Clayloam Upland 8-12" pz.
The native potential plant community on this site is a mixture of perennial grasses and desert shrubs and cacti. Annual forbs and grasses, of both the winter and summer seasons, are very important in the plant community in their respective (wet) seasons. Tobosa is the dominant perennial grass, with lesser amounts of gramas and threeawns. The cover of some shallow rooted grass species, like curley mesquite, fluctuate widely from wet to dry years.
Figure 6. 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 | 125 | 200 | 500 |
| Forb | 5 | 50 | 175 |
| Shrub/Vine | 17 | 50 | 110 |
| Total | 147 | 300 | 785 |
Table 6. Soil surface cover
| Tree basal cover | 0% |
|---|---|
| Shrub/vine/liana basal cover | 0-1% |
| Grass/grasslike basal cover | 1-3% |
| Forb basal cover | 0-1% |
| Non-vascular plants | 0% |
| Biological crusts | 0-10% |
| Litter | 10-75% |
| Surface fragments >0.25" and <=3" | 15-50% |
| Surface fragments >3" | 0-10% |
| Bedrock | 0% |
| Water | 0% |
| Bare ground | 5-75% |
Table 7. Canopy structure (% cover)
| Height Above Ground (ft) | Tree | Shrub/Vine | Grass/ Grasslike |
Forb |
|---|---|---|---|---|
| <0.5 | – | 1-5% | 1-10% | 1-10% |
| >0.5 <= 1 | – | 1-5% | 1-10% | 1-20% |
| >1 <= 2 | – | 1-5% | 5-10% | 0-10% |
| >2 <= 4.5 | – | 1-5% | 0-2% | 0-2% |
| >4.5 <= 13 | – | 0-5% | – | – |
| >13 <= 40 | – | – | – | – |
| >40 <= 80 | – | – | – | – |
| >80 <= 120 | – | – | – | – |
| >120 | – | – | – | – |
Community 1.2
Annual Forbs and Grasses
This community phase follows a drought period during which the shallow-rooted perennial grasses such as curly mesquite are negatively impacted. Annuals dominate the subsequent bare areas, shrubs and succulents may or may not increase, tobosa is slightly reduced.
Pathway 1.1a
Community 1.1 to 1.2
Dry weather cycles such as La Nina accompanied by below average monsoons.
Conservation practices
| Upland Wildlife Habitat Management | |
|---|---|
| Prescribed Grazing |
Pathway 1.2a
Community 1.2 to 1.1
Wet weather cycles such as El Nino and higher than average monsoons.
Conservation practices
| Upland Wildlife Habitat Management | |
|---|---|
| Prescribed Grazing |
State 2
Shrubs, tobosa
Community 2.1
Desert Shrubland
This state occurs where shrub and cacti species including mesquite and prickly pear have increased to dominate the plant community but there is still a remnant cover of tobosa and other native grasses and forbs. Shrub increases are due to the interaction of drought and continuous grazing and perhaps to climatic warming (prickly pear).
State 3
Annual Forbs & Grasses
Community 3.1
Annuals
This state occurs where the native grass cover has been depleted due too the interactions of fire, drought and continuous grazing. Annual grasses and forbs (native and non-native) dominate the plant community. Some situations may be due to the cultivation for irrigation and subsequent abandonment.
State 4
Eroded
Community 4.1
Eroded, with or without Shrubs
This State is characterized by loss of soil site stability due to exposed, compacted soil,and accelerated erosion (sheet, rill, and gully erosion); hydrologic functioning is impaired due to lack of infiltration; the biotic community is no longer intact. Native and non-native annuals fluctuate with weather patterns. Perennial grasses and forbs are largely absent. Shrubs and succulents may or may not be present.
Transition T1A
State 1 to 2
Continous unmanaged grazing and/or a long-term dry weather cycle will negatively impact the perennial herbaceous component of the plant community. Shrubs will largely be unaffected and continue to expand in canopy cover. Climatic shift toward higher amounts of winter rainfall and lesser amounts summer rainfall favors shrub and, in particular, succulent growth.
Transition T1B
State 1 to 3
Continous unmanaged grazing and repeated burning to remove undesirable old growth from tobosa. Some situations may have arisen from cultivation and abandonment of irrigated farming.
Restoration pathway R2A
State 2 to 1
Managed grazing and, as needed, woody species control and/or native species seeding.
Conservation practices
| Brush Management | |
|---|---|
| Range Planting | |
| Upland Wildlife Habitat Management | |
| Prescribed Grazing |
Transition T2A
State 2 to 4
Long-term unmanaged grazing negatively impacts above-ground herbaceous growth and causes soil compaction limiting root development. Animal trailing and soil surface compaction compound the affect of plant community changes (increased shrub/decreased perennial grass community) to increase surface water run-off.
Transition T3A
State 3 to 4
Restoration pathway R4A
State 4 to 2
Restoration of this state involves a mechanical woody species control and native herbaceous species planting plus control structures to inhibit gully and rill erosion.
Conservation practices
| Brush Management | |
|---|---|
| Critical Area Planting | |
| Grade Stabilization Structure | |
| Access Control | |
| Grazing Land Mechanical Treatment | |
| Range Planting | |
| Heavy Use Area Protection | |
| Upland Wildlife Habitat Management | |
| Grade Stabilization Structure-Tire Bales | |
| Prescribed Grazing |
Restoration pathway R4B
State 4 to 3
Restoration of this state involves a broad spectrum approach to slow erosion and provide short-term infiltration during native seed (in situ or planted) establishment. Projects involve treating the compacted areas with contour ripping, mulching, and native seed planting; rills and gullies should be treated with mechanical control structures.
Conservation practices
| Brush Management | |
|---|---|
| Critical Area Planting | |
| Grade Stabilization Structure | |
| Access Control | |
| Mulching | |
| Grazing Land Mechanical Treatment | |
| Range Planting | |
| Rock Barrier | |
| Heavy Use Area Protection | |
| Upland Wildlife Habitat Management | |
| Livestock Use Area Protection | |
| Grade Stabilization Structure-Tire Bales | |
| Prescribed Grazing | |
| Road/Trail/Landing Closure and Treatment | |
| Grazing Management Plan - Written | |
| Grazing Management Plan - Applied |
Additional community tables
Table 8. Community 1.1 plant community composition
| Group | Common name | Symbol | Scientific name | Annual production (lb/acre) | Foliar cover (%) | |
|---|---|---|---|---|---|---|
|
Grass/Grasslike
|
||||||
| 1 | Dominant Perennial Grass | 100–200 | ||||
| tobosagrass | PLMU3 | Pleuraphis mutica | 100–200 | – | ||
| 2 | Miscellaneous Perennial Grasses | 13–100 | ||||
| black grama | BOER4 | Bouteloua eriopoda | 10–50 | – | ||
| curly-mesquite | HIBE | Hilaria belangeri | 1–50 | – | ||
| Arizona cottontop | DICA8 | Digitaria californica | 0–20 | – | ||
| bush muhly | MUPO2 | Muhlenbergia porteri | 1–20 | – | ||
| sideoats grama | BOCU | Bouteloua curtipendula | 1–20 | – | ||
| Hall's panicgrass | PAHA | Panicum hallii | 0–10 | – | ||
| vine mesquite | PAOB | Panicum obtusum | 0–10 | – | ||
| burrograss | SCBR2 | Scleropogon brevifolius | 0–10 | – | ||
| plains bristlegrass | SEVU2 | Setaria vulpiseta | 0–10 | – | ||
| green sprangletop | LEDU | Leptochloa dubia | 0–10 | – | ||
| blue grama | BOGR2 | Bouteloua gracilis | 0–10 | – | ||
| cane bluestem | BOBA3 | Bothriochloa barbinodis | 0–5 | – | ||
| sand dropseed | SPCR | Sporobolus cryptandrus | 0–5 | – | ||
| squirreltail | ELEL5 | Elymus elymoides | 0–2 | – | ||
| tanglehead | HECO10 | Heteropogon contortus | 0–2 | – | ||
| 3 | Perennial threeawns | 10–100 | ||||
| Parish's threeawn | ARPUP5 | Aristida purpurea var. parishii | 0–25 | – | ||
| spidergrass | ARTE3 | Aristida ternipes | 5–25 | – | ||
| purple threeawn | ARPU9 | Aristida purpurea | 5–25 | – | ||
| Fendler threeawn | ARPUL | Aristida purpurea var. longiseta | 0–15 | – | ||
| spidergrass | ARTEG | Aristida ternipes var. gentilis | 0–15 | – | ||
| poverty threeawn | ARDI5 | Aristida divaricata | 0–5 | – | ||
| blue threeawn | ARPUN | Aristida purpurea var. nealleyi | 0–5 | – | ||
| 4 | Annual grasses | 1–100 | ||||
| mucronate sprangeltop | LEPAB | Leptochloa panicea ssp. brachiata | 0–25 | – | ||
| sixweeks threeawn | ARAD | Aristida adscensionis | 1–25 | – | ||
| sixweeks fescue | VUOC | Vulpia octoflora | 1–25 | – | ||
| needle grama | BOAR | Bouteloua aristidoides | 0–20 | – | ||
| sixweeks grama | BOBA2 | Bouteloua barbata | 0–20 | – | ||
| Arizona signalgrass | URAR | Urochloa arizonica | 0–20 | – | ||
| Rothrock's grama | BORO2 | Bouteloua rothrockii | 0–15 | – | ||
| prairie threeawn | AROL | Aristida oligantha | 1–10 | – | ||
| witchgrass | PACA6 | Panicum capillare | 0–10 | – | ||
| Mexican panicgrass | PAHI5 | Panicum hirticaule | 0–10 | – | ||
| Bigelow's bluegrass | POBI | Poa bigelovii | 0–5 | – | ||
| Arizona brome | BRAR4 | Bromus arizonicus | 0–5 | – | ||
| feather fingergrass | CHVI4 | Chloris virgata | 0–5 | – | ||
| tapertip cupgrass | ERACA | Eriochloa acuminata var. acuminata | 0–5 | – | ||
| desert lovegrass | ERPEM | Eragrostis pectinacea var. miserrima | 0–5 | – | ||
| tufted lovegrass | ERPEP2 | Eragrostis pectinacea var. pectinacea | 0–5 | – | ||
| Mexican sprangletop | LEFUU | Leptochloa fusca ssp. uninervia | 0–5 | – | ||
| delicate muhly | MUFR | Muhlenbergia fragilis | 0–2 | – | ||
| littleseed muhly | MUMI | Muhlenbergia microsperma | 0–2 | – | ||
|
Forb
|
||||||
| 5 | Perennial Forbs | 5–25 | ||||
| dwarf desertpeony | ACNA2 | Acourtia nana | 1–10 | – | ||
| bluedicks | DICA14 | Dichelostemma capitatum | 0–5 | – | ||
| weakleaf bur ragweed | AMCO3 | Ambrosia confertiflora | 1–5 | – | ||
| Indian rushpea | HOGL2 | Hoffmannseggia glauca | 1–5 | – | ||
| slender janusia | JAGR | Janusia gracilis | 1–5 | – | ||
| desert globemallow | SPAM2 | Sphaeralcea ambigua | 1–5 | – | ||
| brownplume wirelettuce | STPA4 | Stephanomeria pauciflora | 0–5 | – | ||
| slender poreleaf | POGR5 | Porophyllum gracile | 1–5 | – | ||
| Coues' cassia | SECO10 | Senna covesii | 0–1 | – | ||
| silverleaf nightshade | SOEL | Solanum elaeagnifolium | 0–1 | – | ||
| pricklyleaf dogweed | THAC | Thymophylla acerosa | 0–1 | – | ||
| Rocky Mountain zinnia | ZIGR | Zinnia grandiflora | 0–1 | – | ||
| ragged nettlespurge | JAMA | Jatropha macrorhiza | 0–1 | – | ||
| San Pedro daisy | LAPO4 | Lasianthaea podocephala | 0–1 | – | ||
| Parry's false prairie-clover | MAPA7 | Marina parryi | 0–1 | – | ||
| lacy tansyaster | MAPIP4 | Machaeranthera pinnatifida ssp. pinnatifida var. pinnatifida | 0–1 | – | ||
| plains blackfoot | MELE2 | Melampodium leucanthum | 0–1 | – | ||
| wishbone-bush | MILAV | Mirabilis laevis var. villosa | 0–1 | – | ||
| desert tobacco | NIOB | Nicotiana obtusifolia | 0–1 | – | ||
| tuber anemone | ANTU | Anemone tuberosa | 0–1 | – | ||
| narrowleaf silverbush | ARLA12 | Argythamnia lanceolata | 0–1 | – | ||
| New Mexico silverbush | ARNE2 | Argythamnia neomexicana | 0–1 | – | ||
| perennial rockcress | ARPE2 | Arabis perennans | 0–1 | – | ||
| dense ayenia | AYMI | Ayenia microphylla | 0–1 | – | ||
| hairyseed bahia | BAAB | Bahia absinthifolia | 0–1 | – | ||
| desert marigold | BAMU | Baileya multiradiata | 0–1 | – | ||
| scarlet spiderling | BOCO | Boerhavia coccinea | 0–1 | – | ||
| desert mariposa lily | CAKE | Calochortus kennedyi | 0–1 | – | ||
| sego lily | CANU3 | Calochortus nuttallii | 0–1 | – | ||
| whitemargin sandmat | CHAL11 | Chamaesyce albomarginata | 0–1 | – | ||
| leatherweed | CRPO5 | Croton pottsii | 0–1 | – | ||
| fingerleaf gourd | CUDI | Cucurbita digitata | 0–1 | – | ||
| coyote gourd | CUPA | Cucurbita palmata | 0–1 | – | ||
| spreading fleabane | ERDI4 | Erigeron divergens | 0–1 | – | ||
| desert trumpet | ERIN4 | Eriogonum inflatum | 0–1 | – | ||
| southwestern mock vervain | GLGO | Glandularia gooddingii | 0–1 | – | ||
| brownfoot | ACWR5 | Acourtia wrightii | 0–1 | – | ||
| poreleaf dogweed | ADPO2 | Adenophyllum porophyllum | 0–1 | – | ||
| trailing windmills | ALIN | Allionia incarnata | 0–1 | – | ||
| largeflower onion | ALMA4 | Allium macropetalum | 0–1 | – | ||
| 6 | Annual forbs | 0–150 | ||||
| California poppy | ESCAM | Eschscholzia californica ssp. mexicana | 0–25 | – | ||
| western tansymustard | DEPI | Descurainia pinnata | 0–20 | – | ||
| Arizona popcornflower | PLAR | Plagiobothrys arizonicus | 0–20 | – | ||
| desert Indianwheat | PLOV | Plantago ovata | 0–20 | – | ||
| combseed | PECTO | Pectocarya | 0–20 | – | ||
| tanseyleaf tansyaster | MATA2 | Machaeranthera tanacetifolia | 0–15 | – | ||
| shaggyfruit pepperweed | LELA | Lepidium lasiocarpum | 0–15 | – | ||
| intermediate pepperweed | LEVIM | Lepidium virginicum var. medium | 0–15 | – | ||
| coastal bird's-foot trefoil | LOSAB | Lotus salsuginosus var. brevivexillus | 0–15 | – | ||
| bristly fiddleneck | AMTE3 | Amsinckia tessellata | 0–15 | – | ||
| Arizona poppy | KAGR | Kallstroemia grandiflora | 0–10 | – | ||
| miniature woollystar | ERDI2 | Eriastrum diffusum | 0–10 | – | ||
| Coulter's lupine | LUSP2 | Lupinus sparsiflorus | 0–10 | – | ||
| manybristle chinchweed | PEPA2 | Pectis papposa | 0–10 | – | ||
| New Mexico plumeseed | RANE | Rafinesquia neomexicana | 0–5 | – | ||
| Nuttall's povertyweed | MONU | Monolepis nuttalliana | 0–5 | – | ||
| slender goldenweed | MAGR10 | Machaeranthera gracilis | 0–5 | – | ||
| sorrel buckwheat | ERPO4 | Eriogonum polycladon | 0–5 | – | ||
| Texas stork's bill | ERTE13 | Erodium texanum | 0–5 | – | ||
| Gordon's bladderpod | LEGO | Lesquerella gordonii | 0–5 | – | ||
| foothill deervetch | LOHU2 | Lotus humistratus | 0–5 | – | ||
| wedgeleaf draba | DRCU | Draba cuneifolia | 0–5 | – | ||
| flatcrown buckwheat | ERDE6 | Eriogonum deflexum | 0–5 | – | ||
| cryptantha | CRYPT | Cryptantha | 0–5 | – | ||
| pitseed goosefoot | CHBE4 | Chenopodium berlandieri | 0–5 | – | ||
| milkvetch | ASTRA | Astragalus | 0–5 | – | ||
| wheelscale saltbush | ATEL | Atriplex elegans | 0–5 | – | ||
| Coulter's spiderling | BOCO2 | Boerhavia coulteri | 0–5 | – | ||
| carelessweed | AMPA | Amaranthus palmeri | 0–5 | – | ||
| white tackstem | CAWR | Calycoseris wrightii | 0–2 | – | ||
| fringed redmaids | CACI2 | Calandrinia ciliata | 0–2 | – | ||
| brittle spineflower | CHBR | Chorizanthe brevicornu | 0–2 | – | ||
| hyssopleaf sandmat | CHHY3 | Chamaesyce hyssopifolia | 0–2 | – | ||
| Esteve's pincushion | CHST | Chaenactis stevioides | 0–2 | – | ||
| hairy prairie clover | DAMO | Dalea mollis | 0–2 | – | ||
| American wild carrot | DAPU3 | Daucus pusillus | 0–2 | – | ||
| Arizona lupine | LUAR4 | Lupinus arizonicus | 0–2 | – | ||
| hairy desertsunflower | GECA2 | Geraea canescens | 0–2 | – | ||
| star gilia | GIST | Gilia stellata | 0–2 | – | ||
| longleaf false goldeneye | HELOA2 | Heliomeris longifolia var. annua | 0–2 | – | ||
| woolly tidestromia | TILA2 | Tidestromia lanuginosa | 0–2 | – | ||
| woollyhead neststraw | STMI2 | Stylocline micropoides | 0–2 | – | ||
| sleepy silene | SIAN2 | Silene antirrhina | 0–2 | – | ||
| green carpetweed | MOVE | Mollugo verticillata | 0–2 | – | ||
| phacelia | PHACE | Phacelia | 0–2 | – | ||
| desert evening primrose | OEPR | Oenothera primiveris | 0–2 | – | ||
| Florida pellitory | PAFL3 | Parietaria floridana | 0–2 | – | ||
| chia | SACO6 | Salvia columbariae | 0–1 | – | ||
| sawtooth sage | SASU7 | Salvia subincisa | 0–1 | – | ||
| spreading fanpetals | SIAB | Sida abutifolia | 0–1 | – | ||
| bristly nama | NAHI | Nama hispidum | 0–1 | – | ||
| glandular threadplant | NEGL | Nemacladus glanduliferus | 0–1 | – | ||
| Fendler's desertdandelion | MAFE | Malacothrix fendleri | 0–1 | – | ||
| whitestem blazingstar | MEAL6 | Mentzelia albicaulis | 0–1 | – | ||
| Coulter's globemallow | SPCO2 | Sphaeralcea coulteri | 0–1 | – | ||
| doubleclaw | PRPA2 | Proboscidea parviflora | 0–1 | – | ||
| sand fringepod | THCU | Thysanocarpus curvipes | 0–1 | – | ||
| tumblemustard | THELY3 | Thelypodiopsis | 0–1 | – | ||
| camphorweed | HESU3 | Heterotheca subaxillaris | 0–1 | – | ||
| crestrib morning-glory | IPCO2 | Ipomoea costellata | 0–1 | – | ||
| common woolly sunflower | ERLA6 | Eriophyllum lanatum | 0–1 | – | ||
| Mexican fireplant | EUHE4 | Euphorbia heterophylla | 0–1 | – | ||
| scrambled eggs | COAU2 | Corydalis aurea | 0–1 | – | ||
| exserted Indian paintbrush | CAEXE | Castilleja exserta ssp. exserta | 0–1 | – | ||
| yellow tackstem | CAPA7 | Calycoseris parryi | 0–1 | – | ||
| hoary bowlesia | BOIN3 | Bowlesia incana | 0–1 | – | ||
| southwestern pricklypoppy | ARPL3 | Argemone pleiacantha | 0–1 | – | ||
| annual agoseris | AGHE2 | Agoseris heterophylla | 0–1 | – | ||
|
Shrub/Vine
|
||||||
| 7 | Dominant shrubs | 10–50 | ||||
| jojoba | SICH | Simmondsia chinensis | 0–40 | – | ||
| western honey mesquite | PRGLT | Prosopis glandulosa var. torreyana | 5–20 | – | ||
| creosote bush | LATR2 | Larrea tridentata | 0–10 | – | ||
| whitethorn acacia | ACCO2 | Acacia constricta | 0–10 | – | ||
| longleaf jointfir | EPTR | Ephedra trifurca | 0–5 | – | ||
| fourwing saltbush | ATCA2 | Atriplex canescens | 0–5 | – | ||
| 8 | Miscellaneous shrubs | 0–10 | ||||
| catclaw acacia | ACGR | Acacia greggii | 0–1 | – | ||
| crucifixion thorn | CAHO3 | Canotia holacantha | 0–1 | – | ||
| spiny hackberry | CEEH | Celtis ehrenbergiana | 0–1 | – | ||
| American tarwort | FLCE | Flourensia cernua | 0–1 | – | ||
| ocotillo | FOSP2 | Fouquieria splendens | 0–1 | – | ||
| water jacket | LYAN | Lycium andersonii | 0–1 | – | ||
| Berlandier's wolfberry | LYBE | Lycium berlandieri | 0–1 | – | ||
| pale desert-thorn | LYPA | Lycium pallidum | 0–1 | – | ||
| catclaw mimosa | MIACB | Mimosa aculeaticarpa var. biuncifera | 0–1 | – | ||
| blue paloverde | PAFL6 | Parkinsonia florida | 0–1 | – | ||
| yellow paloverde | PAMI5 | Parkinsonia microphylla | 0–1 | – | ||
| lotebush | ZIOB | Ziziphus obtusifolia | 0–1 | – | ||
| 9 | Half shrubs | 2–30 | ||||
| fairyduster | CAER | Calliandra eriophylla | 1–15 | – | ||
| desert zinnia | ZIAC | Zinnia acerosa | 0–10 | – | ||
| rough menodora | MESC | Menodora scabra | 0–5 | – | ||
| broom snakeweed | GUSA2 | Gutierrezia sarothrae | 0–5 | – | ||
| littleleaf ratany | KRER | Krameria erecta | 1–5 | – | ||
| winterfat | KRLA2 | Krascheninnikovia lanata | 0–1 | – | ||
| burroweed | ISTE2 | Isocoma tenuisecta | 0–1 | – | ||
| turpentine bush | ERLA12 | Ericameria laricifolia | 0–1 | – | ||
| threadleaf snakeweed | GUMI | Gutierrezia microcephala | 0–1 | – | ||
| rayless goldenhead | ACSP | Acamptopappus sphaerocephalus | 0–1 | – | ||
| shortleaf baccharis | BABR | Baccharis brachyphylla | 0–1 | – | ||
| 10 | Succulents | 5–20 | ||||
| devil's cholla | GRKU | Grusonia kunzei | 1–5 | – | ||
| cactus apple | OPEN3 | Opuntia engelmannii | 0–5 | – | ||
| tulip pricklypear | OPPH | Opuntia phaeacantha | 1–5 | – | ||
| banana yucca | YUBA | Yucca baccata | 0–5 | – | ||
| soaptree yucca | YUEL | Yucca elata | 0–2 | – | ||
| purple pricklypear | OPMA8 | Opuntia macrocentra | 0–2 | – | ||
| Christmas cactus | CYLE8 | Cylindropuntia leptocaulis | 0–2 | – | ||
| walkingstick cactus | CYSP8 | Cylindropuntia spinosior | 0–1 | – | ||
| Engelmann's hedgehog cactus | ECEN | Echinocereus engelmannii | 0–1 | – | ||
| pinkflower hedgehog cactus | ECFA | Echinocereus fasciculatus | 0–1 | – | ||
| candy barrelcactus | FEWI | Ferocactus wislizeni | 0–1 | – | ||
| Graham's nipple cactus | MAGR9 | Mammillaria grahamii | 0–1 | – | ||
| buck-horn cholla | CYAC8 | Cylindropuntia acanthocarpa | 0–1 | – | ||
Interpretations
Animal community
This site produces some perennial forage for livestock. It wet (El Nino) winters it produces a tremendous amount of annual forbs and grasses, all of which are excellent forage. The site is home to a variety of small mammals and birds and their associated predators. It is mainly a foraging area for larger mammals like mule deer and javalina.
Hydrological functions
These soils are heavy textured and good producers of runoff.
Recreational uses
Hunting, horseback riding, hiking, wildlife observation, photography, rock hounding and bird watching.
Wood products
Limited mesquite wood for campfires.
Other products
Red clay for pot making.
Supporting information
Contributors
Dan Robinett
Larry D. Ellicott
Steve Barker
Unknown
Approval
Curtis Talbot, 4/09/2021
Rangeland health reference sheet
Interpreting Indicators of Rangeland Health is a qualitative assessment protocol used to determine ecosystem condition based on benchmark characteristics described in the Reference Sheet. A suite of 17 (or more) indicators are typically considered in an assessment. The ecological site(s) representative of an assessment location must be known prior to applying the protocol and must be verified based on soils and climate. Current plant community cannot be used to identify the ecological site.
| Author(s)/participant(s) | Wilma Renken, Dan Robinett, Larry Humphrey |
|---|---|
| Contact for lead author | USDA-NRCS Tucson MLRA Soil Survey Office |
| Date | 12/12/2012 |
| Approved by | Curtis Talbot |
| Approval date | |
| Composition (Indicators 10 and 12) based on | Annual Production |
Indicators
-
Number and extent of rills:
None -
Presence of water flow patterns:
Water flow paths occupy less than 5% of the surface area. Sheet flow predominates as a process on this site with water flow patterns generated from sheet flow off bare areas. Sheet flow lengths are less than 10 feet. Vegetated areas are densely covered with no visible flow patterns. -
Number and height of erosional pedestals or terracettes:
Pedestals are infrequent on all longer lived grasses and sub-shrubs. Terracettes are not common on the site. -
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
ESD cover ranges for bare soil is 5-75%, gravel ranges from 15-50% and basal cover of live perennial grasses is 1-3%. Bare areas not covered by perennial plant canopy are moderately sized (2-3 ft in diameter) and generally connected. Bare areas make up approximately 50% of the area. -
Number of gullies and erosion associated with gullies:
None -
Extent of wind scoured, blowouts and/or depositional areas:
None -
Amount of litter movement (describe size and distance expected to travel):
Fine litter size classes are moving less than a foot in sheet flow areas. Coarse litter stays in place. -
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Values from soil slake test score 2-3 on bare areas and 4-6 from protected areas. -
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
A horizon is a gravelly sandy loam 0.5 inches thick, structureless. Colors are 5 YR 5/4 dry and 5 YR 3/4 moist. -
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Perennial grasses dominate the site. Hydrology functions are sheet flow run-off originating on bare areas, run-off slowing and infiltration occurring within perennial grass patches. Total canopy cover approximately 40-45%. Perennial grass canopy = 27-37%, succulent canopy = 1-5%, shrubs and half-shrubs = 1-5%. Annual grass canopy fluctuates with seasonal rainfall; canopy cover can exceed 40% and mask the vegetation distribution pattern. Perennial grasses exhibit patch-distribution with scattered shrubs and succulents. -
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
None present, average depth of penetration from an ARS field penetrometer with a 2.2 kg. sliding hammer is 5.1 cm. The dense argillic horizon at 3 inches can be mistaken for a compacted layer. -
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:
Dominant perennial grass (tobosa)>Sub-dominant:
> miscellaneous perennial grasses = perennial three-awns = dominant shrubs >/= annual forbs >/= annual grasses >Other:
> half-shrubs, succulents, misc.shrubs, perennial forbsAdditional:
annual grasses and forbs can fluctuate within ranking based on seasonal precipitation -
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
Mortality due to drought (2009 and very dry winter spring of 2011) about 20% on cane cholla. All other species show only natural rates of approximately 5-10% mortality. -
Average percent litter cover (%) and depth ( in):
Litter cover ranges from 10-75% on this site. Litter cover was 65% on this date. Ground cover was collected as point cover data concurrently with pace frequency method (300 pts). -
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
147 lbs/ac. in a below average year; 300 lbs/ac. in an average year; 785 lbs/ac. in an above average year. Production of summer annual grasses can exceed expected on years with above average seasonal 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:
Cholla and prickly pear common across site with about 300 plants per acre amounting to 4% canopy cover. Mesquite is scattered across site at 1% canopy cover and with a density of 25 plants per acre. Other invasive species: Lehmann lovegrass and Boers lovegrass. -
Perennial plant reproductive capability:
Not impaired on any species.
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The 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.
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