Natural Resources
Conservation Service
Ecological site R040XA110AZ
Limy Slopes 10"-13" p.z.
Accessed: 11/21/2024
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): 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
| R040XA106AZ |
Limy Upland, Deep 10"-13" p.z. |
|---|---|
| R040XA111AZ |
Limy Upland 10"-13" p.z. |
| R040XA114AZ |
Loamy Upland 10"-13" p.z. |
| R040XA115AZ |
Sandy Wash 10"-13" p.z. |
Similar sites
| R041XB207AZ |
Limy Slopes 8-12" p.z. |
|---|---|
| R041XC308AZ |
Limy Slopes 12-16" p.z. |
| R040XB209AZ |
Limy Slopes 7"-10" p.z. |
Table 1. Dominant plant species
| Tree |
(1) Parkinsonia microphylla |
|---|---|
| Shrub |
(1) Larrea tridentata |
| Herbaceous |
(1) Dasyochloa pulchella |
Physiographic features
This site occurs in the upper elevations of the Sonoran Desert in southern Arizona. It occurs on hill-slopes and ridge-tops.
Table 2. Representative physiographic features
| Landforms |
(1)
Hill
(2) Ridge (3) Ballena |
|---|---|
| Flooding frequency | None |
| Ponding frequency | None |
| Elevation | 671 – 1,097 m |
| Slope | 15 – 45% |
| Aspect | N, E, S |
Climatic features
Precipitation in the sub resource area ranges from 10 to 13 inches in the southern part, along the Mexican border with elevations from about 1900 to 3200 feet. Precipitation in the northern part of the resource area ranges from 11 to 14 inches with elevations from about 1700 to 3500 feet. Winter-summer rainfall ratios range from 40%-60% in the southern portions of the land resource unit, to 50%-50% in the central portions, to 60%-40% in the northern part of the land resource unit. As one moves from east to west in this resource area rains become slightly more unpredictable and variable with Coefficients of Variation of annual rainfall equal to 29% at Tucson and 36% at Carefree. Summer rains fall July through Sept., originate in the Gulf of Mexico, and are convective, usually brief, intense thunderstorms. Cool season moisture tends to be frontal, originating in the Pacific and Gulf of California. This winter precipitation falls in widespread storms with long duration and low intensity. Snow is rare and seldom lasts more than an hour or two. May and June are the driest months of the year. Humidity is generally very low.
Winter temperatures are mild, with very few days recording freezing temperatures in the morning. Summer temperatures are warm to hot, with several days in June and July exceeding 105 degrees F.
Both the spring and the summer growing seasons are equally important for perennial grass, forb and shrub growth. Cool and warm season annual forbs and grasses can be common in their respective seasons with above average rainfall. Perennial forage species can remain green throughout the year with available moisture.
Table 3. Representative climatic features
| Frost-free period (average) | 265 days |
|---|---|
| Freeze-free period (average) | 0 days |
| Precipitation total (average) | 330 mm |
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 deep and moderately deep soils formed in limy and gravelly loamy alluvium or colluvium of mixed origin. They are calcareous throughout. Some soil series have lime cemented layers at moderate depths (20-40 inches). Soil surfaces are well covered with rocks and gravels. Plant-soil moisture relationships are fair.
Soils mapped on this site include:
SSA-627 Southern Mohave County MU's Stagecoach-110, 111 & 115, Topowah family-115;
SSA-645 Aguila-Carefree area MU's Nickel-65, 93 & 94;
SSA-661 Eastern Pinal-Southern Gila Counties MU's Haplogypsids-525, Rillino-870;
SSA-666 Northwest Cochise County MU's Redo-247, Redington-475, Stagecoach-490;
SSA-669 Eastern Pima County MU's Stagecoach-61, Redington-66 & Redo-67.
Table 4. Representative soil features
| Surface texture |
(1) Gravelly sandy loam (2) Very gravelly sandy loam (3) Cobbly sandy loam |
|---|---|
| Family particle size |
(1) Loamy |
| Drainage class | Somewhat excessively drained to well drained |
| Permeability class | Rapid to moderately rapid |
| Soil depth | 51 – 152 cm |
| Surface fragment cover <=3" | 20 – 85% |
| Surface fragment cover >3" | 0 – 15% |
| Available water capacity (0-101.6cm) |
5.33 – 12.7 cm |
| Calcium carbonate equivalent (0-101.6cm) |
5 – 30% |
| Electrical conductivity (0-101.6cm) |
0 – 2 mmhos/cm |
| Sodium adsorption ratio (0-101.6cm) |
0 – 2 |
| Soil reaction (1:1 water) (0-101.6cm) |
7.8 – 8.4 |
| Subsurface fragment volume <=3" (Depth not specified) |
15 – 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
Figure 4. State and Transition model, Limy Slopes 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 text
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 7 submodel, plant communities
State 1
Historical Climax Plant Community
Community 1.1
Historical Climax Plant Community
The potential plant community is a diverse community of desert trees, shrubs, cacti, and perennial forbs and grasses. With continuous heavy grazing, herbaceous and suffrutescent forage species are replaced by increases in shrubs, cacti and trees. Well developed gravel covers help protect the soil from erosion. Northern exposures will have more perennial grasses and shrubs like false mesquite, mint bush and janusia. South slopes will be shrubbier and have more sub shrubs like bursage, brittlebush and desert zinnia. This site has a cycle of dominance by saguaro, alternating with large shrubs and trees that act as nurse plants for the giant cacti. This cycle takes approximately 300 years and starts from exceptionally wet years (El Nino) where saguaro establishes in large numbers.
Figure 5. Annual production by plant type (representative values) or group (midpoint values)
Table 5. Annual production by plant type
| Plant type | Low (kg/hectare) |
Representative value (kg/hectare) |
High (kg/hectare) |
|---|---|---|---|
| Grass/Grasslike | 12 | 112 | 370 |
| Shrub/Vine | 95 | 224 | 342 |
| Tree | 17 | 112 | 168 |
| Forb | 29 | 112 | 168 |
| Total | 153 | 560 | 1048 |
Table 6. Soil surface cover
| Tree basal cover | 0-1% |
|---|---|
| Shrub/vine/liana basal cover | 1-5% |
| Grass/grasslike basal cover | 0-1% |
| Forb basal cover | 0-1% |
| Non-vascular plants | 0% |
| Biological crusts | 1-15% |
| Litter | 5-45% |
| Surface fragments >0.25" and <=3" | 20-85% |
| Surface fragments >3" | 0-15% |
| Bedrock | 0% |
| Water | 0% |
| Bare ground | 5-45% |
Table 7. Canopy structure (% cover)
| Height Above Ground (m) | Tree | Shrub/Vine | Grass/ Grasslike |
Forb |
|---|---|---|---|---|
| <0.15 | – | 0-1% | 1-10% | 1-15% |
| >0.15 <= 0.3 | – | 0-2% | 1-10% | 1-10% |
| >0.3 <= 0.6 | – | 1-5% | 0-2% | 0-5% |
| >0.6 <= 1.4 | 0-1% | 1-15% | 0-1% | 0-1% |
| >1.4 <= 4 | 1-10% | 0-2% | – | – |
| >4 <= 12 | 0-1% | – | – | – |
| >12 <= 24 | – | – | – | – |
| >24 <= 37 | – | – | – | – |
| >37 | – | – | – | – |
Figure 6. Plant community growth curve (percent production by month). AZ4013, 40.1 10-13" p.z. other sites. Growth begins in the late winter, goes semi-dormant in the drought period of late May through early July, growth continues in the summer through early fall..
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| J | F | M | A | M | J | J | A | S | O | N | D |
| 0 | 5 | 10 | 20 | 15 | 0 | 5 | 20 | 15 | 5 | 5 | 0 |
State 2
Exotic perennial grasses with natives
Community 2.1
Exotic perennial grasses with natives
This community occurs where bufflegrass and / or fountain grass invade the native plant community. These species occupy the niches of low shrubs like desert zinnia, brittlebush and grasses like black grama, red grama and slim tridens.
State 3
Exotic perennial grasses and fire
Community 3.1
Exotic perennial grasses and fire
This 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 4
Native trees, cacti, shrubs and fire
Community 4.1
Native trees, cacti, shrubs and fire
This plant community occurs as a result of a single hot season fire. Creosotebush, whitethorn, paloverde and saguaro can be severely impacted and may take long periods of time (30-50 years) to recover to pre-fire levels. Perennial and annual grasses and forbs dominate the community for some time until shrubs like ocotillo, whitethorn and jojoba can recover. This plant community can produce enough herbaceous fuel from native species of grasses and / or forbs to carry fire in El Nino years or after unusually wet summers. The natural incidence of fire in this MLRA is very low and fires are much more common from man-made ignitions. Areas of the site close to urban zones or along heavily travelled roads and highways will experience a higher rate of fires.
State 5
Native plant community with exotic annuals
Community 5.1
Native plant community with exotic annuals
This plant community occurs where the native community has been invaded by species like red brome and / or schismus. Red brome occupies the niche of the native winter annual forbs and grasses. This exotic annual grass will fluctuate from nearly nothing in a dry winter to dominance of the understory plant community in a El Nino winter.
State 6
Exotic annuals and fire
Community 6.1
Exotic annuals and fire
This plant community occurs where a native plant community which has been invaded by red brome and / or schismus, and has burned repeatedly. As fires become more frequent the native trees, shrubs and succulents are removed from the plant community and red brome becomes dominant. In areas of the site near urban areas and along heavily travelled roads this will be a more common occurence due to an increased source of ignitions.
State 7
HCPC 2 - Saguaro state
Community 7.1
HCPC 2 - Saguaro state
There is a 300 year cycle on this site that swings between dominance of native trees and large shrubs (that serve as nurse plants) and mature saguaro forest. Saguaro establishes wholesale in very favorable years (El Nino years like 1979 and 1983) only in the presence of plentiful nurse plants like paloverde, mesquite, whitethorn and creosote. As saguaro plants top their nurse plants (40-60 years) the trees and shrubs begin to die. Saguaro stands reach maturity at 150 to 200 years and begin to diminish over the next 100 years as the large shrubs and trees come back into the plant community.
Additional community tables
Table 8. Community 1.1 plant community composition
| Group | Common name | Symbol | Scientific name | Annual production (kg/hectare) | Foliar cover (%) | |
|---|---|---|---|---|---|---|
|
Grass/Grasslike
|
||||||
| 1 | Suffrutescent grasses | 6–140 | ||||
| bush muhly | MUPO2 | Muhlenbergia porteri | 28–56 | – | ||
| black grama | BOER4 | Bouteloua eriopoda | 11–28 | – | ||
| 2 | Subdominant perennial grasses | 6–84 | ||||
| slim tridens | TRMU | Tridens muticus | 1–34 | – | ||
| low woollygrass | DAPU7 | Dasyochloa pulchella | 1–28 | – | ||
| purple threeawn | ARPU9 | Aristida purpurea | 1–22 | – | ||
| blue threeawn | ARPUN | Aristida purpurea var. nealleyi | 0–22 | – | ||
| red grama | BOTR2 | Bouteloua trifida | 0–22 | – | ||
| nineawn pappusgrass | ENDE | Enneapogon desvauxii | 0–11 | – | ||
| Hall's panicgrass | PAHA | Panicum hallii | 0–6 | – | ||
| big galleta | PLRI3 | Pleuraphis rigida | 0–3 | – | ||
| 3 | Misc. perennial grasses | 0–34 | ||||
| spidergrass | ARTE3 | Aristida ternipes | 0–22 | – | ||
| spidergrass | ARTEG | Aristida ternipes var. gentilis | 0–17 | – | ||
| sideoats grama | BOCU | Bouteloua curtipendula | 0–17 | – | ||
| Parish's threeawn | ARPUP5 | Aristida purpurea var. parishii | 0–11 | – | ||
| Arizona cottontop | DICA8 | Digitaria californica | 0–6 | – | ||
| tanglehead | HECO10 | Heteropogon contortus | 0–6 | – | ||
| plains bristlegrass | SEVU2 | Setaria vulpiseta | 0–6 | – | ||
| spike dropseed | SPCO4 | Sporobolus contractus | 0–6 | – | ||
| sand dropseed | SPCR | Sporobolus cryptandrus | 0–6 | – | ||
| mesa dropseed | SPFL2 | Sporobolus flexuosus | 0–6 | – | ||
| Indian ricegrass | ACHY | Achnatherum hymenoides | 0–2 | – | ||
| desert needlegrass | ACSP12 | Achnatherum speciosum | 0–2 | – | ||
| cotta grass | COPA13 | Cottea pappophoroides | 0–1 | – | ||
| 4 | Annual grasses | 1–112 | ||||
| sixweeks grama | BOBA2 | Bouteloua barbata | 1–56 | – | ||
| Mexican panicgrass | PAHI5 | Panicum hirticaule | 0–17 | – | ||
| sixweeks threeawn | ARAD | Aristida adscensionis | 0–17 | – | ||
| prairie threeawn | AROL | Aristida oligantha | 0–17 | – | ||
| needle grama | BOAR | Bouteloua aristidoides | 0–17 | – | ||
| mucronate sprangeltop | LEPAB | Leptochloa panicea ssp. brachiata | 0–11 | – | ||
| Bigelow's bluegrass | POBI | Poa bigelovii | 0–6 | – | ||
| sixweeks fescue | VUOC | Vulpia octoflora | 0–6 | – | ||
| Rothrock's grama | BORO2 | Bouteloua rothrockii | 0–6 | – | ||
| desert lovegrass | ERPEM | Eragrostis pectinacea var. miserrima | 0–6 | – | ||
| tufted lovegrass | ERPEP2 | Eragrostis pectinacea var. pectinacea | 0–2 | – | ||
| feather fingergrass | CHVI4 | Chloris virgata | 0–2 | – | ||
| Arizona brome | BRAR4 | Bromus arizonicus | 0–1 | – | ||
| Arizona signalgrass | URAR | Urochloa arizonica | 0–1 | – | ||
| delicate muhly | MUFR | Muhlenbergia fragilis | 0–1 | – | ||
| littleseed muhly | MUMI | Muhlenbergia microsperma | 0–1 | – | ||
|
Forb
|
||||||
| 5 | Perennial forbs | 6–56 | ||||
| paleface | HIDE | Hibiscus denudatus | 1–17 | – | ||
| slender janusia | JAGR | Janusia gracilis | 1–17 | – | ||
| lacy tansyaster | MAPIP4 | Machaeranthera pinnatifida ssp. pinnatifida var. pinnatifida | 1–11 | – | ||
| red-gland spurge | CHME5 | Chamaesyce melanadenia | 1–11 | – | ||
| leatherweed | CRPOP | Croton pottsii var. pottsii | 0–6 | – | ||
| trailing windmills | ALIN | Allionia incarnata | 1–6 | – | ||
| dense ayenia | AYMI | Ayenia microphylla | 0–6 | – | ||
| hairyseed bahia | BAAB | Bahia absinthifolia | 0–6 | – | ||
| desert marigold | BAMU | Baileya multiradiata | 0–6 | – | ||
| Coues' cassia | SECO10 | Senna covesii | 0–6 | – | ||
| Parry's false prairie-clover | MAPA7 | Marina parryi | 1–6 | – | ||
| desert globemallow | SPAM2 | Sphaeralcea ambigua | 0–6 | – | ||
| California fagonbush | FALA | Fagonia laevis | 0–2 | – | ||
| slender poreleaf | POGR5 | Porophyllum gracile | 0–2 | – | ||
| plains blackfoot | MELE2 | Melampodium leucanthum | 0–2 | – | ||
| weakleaf bur ragweed | AMCO3 | Ambrosia confertiflora | 0–2 | – | ||
| dwarf desertpeony | ACNA2 | Acourtia nana | 0–2 | – | ||
| hairy five eyes | CHSO | Chamaesaracha sordida | 0–2 | – | ||
| desert trumpet | ERIN4 | Eriogonum inflatum | 0–2 | – | ||
| wild dwarf morning-glory | EVAR | Evolvulus arizonicus | 0–1 | – | ||
| desert larkspur | DEPA | Delphinium parishii | 0–1 | – | ||
| tall mountain larkspur | DESC | Delphinium scaposum | 0–1 | – | ||
| bluedicks | DICA14 | Dichelostemma capitatum | 0–1 | – | ||
| spreading fleabane | ERDI4 | Erigeron divergens | 0–1 | – | ||
| brownfoot | ACWR5 | Acourtia wrightii | 0–1 | – | ||
| San Felipe dogweed | ADPO | Adenophyllum porophylloides | 0–1 | – | ||
| narrowleaf silverbush | ARLA12 | Argythamnia lanceolata | 0–1 | – | ||
| climbing wartclub | BOSC | Boerhavia scandens | 0–1 | – | ||
| desert mariposa lily | CAKE | Calochortus kennedyi | 0–1 | – | ||
| naked mariposa lily | CANU2 | Calochortus nudus | 0–1 | – | ||
| wishbone-bush | MILAV | Mirabilis laevis var. villosa | 0–1 | – | ||
| desert tobacco | NIOBO | Nicotiana obtusifolia var. obtusifolia | 0–1 | – | ||
| Parry's beardtongue | PEPA24 | Penstemon parryi | 0–1 | – | ||
| orange fameflower | PHAU13 | Phemeranthus aurantiacus | 0–1 | – | ||
| mesquite mistletoe | PHCA8 | Phoradendron californicum | 0–1 | – | ||
| glandleaf milkwort | POMA7 | Polygala macradenia | 0–1 | – | ||
| spreading fanpetals | SIAB | Sida abutifolia | 0–1 | – | ||
| fringed twinevine | FUCYC | Funastrum cynanchoides ssp. cynanchoides | 0–1 | – | ||
| Davis Mountain mock vervain | GLBIC | Glandularia bipinnatifida var. ciliata | 0–1 | – | ||
| desert rosemallow | HICO | Hibiscus coulteri | 0–1 | – | ||
| spearleaf | MAPA9 | Matelea parvifolia | 0–1 | – | ||
| caliche globemallow | SPLA | Sphaeralcea laxa | 0–1 | – | ||
| brownplume wirelettuce | STPA4 | Stephanomeria pauciflora | 0–1 | – | ||
| Coulter's wrinklefruit | TECO | Tetraclea coulteri | 0–1 | – | ||
| rue of the mountains | THTE2 | Thamnosma texana | 0–1 | – | ||
| 6 | Annual forbs | 1–112 | ||||
| desert Indianwheat | PLOV | Plantago ovata | 1–28 | – | ||
| lyreleaf jewelflower | STCAA | Streptanthus carinatus ssp. arizonicus | 0–28 | – | ||
| bristly fiddleneck | AMTE3 | Amsinckia tessellata | 0–28 | – | ||
| California poppy | ESCAM | Eschscholzia californica ssp. mexicana | 0–28 | – | ||
| Arizona phacelia | PHAR13 | Phacelia arizonica | 0–28 | – | ||
| cleftleaf wildheliotrope | PHCR | Phacelia crenulata | 0–28 | – | ||
| Coulter's lupine | LUSP2 | Lupinus sparsiflorus | 0–22 | – | ||
| foothill deervetch | LOHU2 | Lotus humistratus | 0–17 | – | ||
| western tansymustard | DEPI | Descurainia pinnata | 0–17 | – | ||
| flatcrown buckwheat | ERDE6 | Eriogonum deflexum | 0–17 | – | ||
| exserted Indian paintbrush | CAEXE | Castilleja exserta ssp. exserta | 0–17 | – | ||
| woolly plantain | PLPA2 | Plantago patagonica | 0–17 | – | ||
| thelypody | THELY | Thelypodium | 0–17 | – | ||
| woolly tidestromia | TILA2 | Tidestromia lanuginosa | 0–11 | – | ||
| chia | SACO6 | Salvia columbariae | 0–11 | – | ||
| yellow tackstem | CAPA7 | Calycoseris parryi | 0–11 | – | ||
| Coulter's spiderling | BOCO2 | Boerhavia coulteri | 0–11 | – | ||
| white tackstem | CAWR | Calycoseris wrightii | 0–11 | – | ||
| Gordon's bladderpod | LEGO | Lesquerella gordonii | 0–11 | – | ||
| shaggyfruit pepperweed | LELA | Lepidium lasiocarpum | 0–11 | – | ||
| coastal bird's-foot trefoil | LOSAB | Lotus salsuginosus var. brevivexillus | 0–6 | – | ||
| Arizona lupine | LUAR4 | Lupinus arizonicus | 0–6 | – | ||
| slender goldenweed | MAGR10 | Machaeranthera gracilis | 0–6 | – | ||
| mesa tansyaster | MATA | Machaeranthera tagetina | 0–6 | – | ||
| tanseyleaf tansyaster | MATA2 | Machaeranthera tanacetifolia | 0–6 | – | ||
| miniature woollystar | ERDI2 | Eriastrum diffusum | 0–6 | – | ||
| Texas stork's bill | ERTE13 | Erodium texanum | 0–6 | – | ||
| Arizona poppy | KAGR | Kallstroemia grandiflora | 0–6 | – | ||
| California goldfields | LACAC2 | Lasthenia californica ssp. californica | 0–6 | – | ||
| American wild carrot | DAPU3 | Daucus pusillus | 0–6 | – | ||
| pitseed goosefoot | CHBE4 | Chenopodium berlandieri | 0–6 | – | ||
| brittle spineflower | CHBR | Chorizanthe brevicornu | 0–6 | – | ||
| pincushion flower | CHFR | Chaenactis fremontii | 0–6 | – | ||
| smallflowered milkvetch | ASNU4 | Astragalus nuttallianus | 0–6 | – | ||
| wheelscale saltbush | ATEL | Atriplex elegans | 0–6 | – | ||
| New Mexico plumeseed | RANE | Rafinesquia neomexicana | 0–6 | – | ||
| combseed | PECTO | Pectocarya | 0–6 | – | ||
| manybristle chinchweed | PEPA2 | Pectis papposa | 0–6 | – | ||
| sleepy silene | SIAN2 | Silene antirrhina | 0–2 | – | ||
| Louisiana vetch | VILU | Vicia ludoviciana | 0–2 | – | ||
| Arizona popcornflower | PLAR | Plagiobothrys arizonicus | 0–2 | – | ||
| white easterbonnets | ANLA7 | Antheropeas lanosum | 0–2 | – | ||
| hyssopleaf sandmat | CHHY3 | Chamaesyce hyssopifolia | 0–2 | – | ||
| Esteve's pincushion | CHST | Chaenactis stevioides | 0–2 | – | ||
| buckwheat | ERIOG | Eriogonum | 0–2 | – | ||
| glandular threadplant | NEGL | Nemacladus glanduliferus | 0–2 | – | ||
| distant phacelia | PHDI | Phacelia distans | 0–2 | – | ||
| fringed amaranth | AMFI | Amaranthus fimbriatus | 0–2 | – | ||
| slimjim bean | PHFI3 | Phaseolus filiformis | 0–1 | – | ||
| desert evening primrose | OEPR | Oenothera primiveris | 0–1 | – | ||
| Florida pellitory | PAFL3 | Parietaria floridana | 0–1 | – | ||
| California desertdandelion | MACA6 | Malacothrix californica | 0–1 | – | ||
| whitestem blazingstar | MEAL6 | Mentzelia albicaulis | 0–1 | – | ||
| Lindley's silverpuffs | MILI5 | Microseris lindleyi | 0–1 | – | ||
| Nuttall's povertyweed | MONU | Monolepis nuttalliana | 0–1 | – | ||
| bristly nama | NAHI | Nama hispidum | 0–1 | – | ||
| Arizona cottonrose | LOAR12 | Logfia arizonica | 0–1 | – | ||
| Abert's buckwheat | ERAB2 | Eriogonum abertianum | 0–1 | – | ||
| flatspine stickseed | LAOCO | Lappula occidentalis var. occidentalis | 0–1 | – | ||
| Thurber's buckwheat | ERTH3 | Eriogonum thurberi | 0–1 | – | ||
| Mexican fireplant | EUHE4 | Euphorbia heterophylla | 0–1 | – | ||
| dainty desert hideseed | EUMI2 | Eucrypta micrantha | 0–1 | – | ||
| spring pygmycudweed | EVVE | Evax verna | 0–1 | – | ||
| limestone bedstraw | GAPR | Galium proliferum | 0–1 | – | ||
| hairy desertsunflower | GECA2 | Geraea canescens | 0–1 | – | ||
| star gilia | GIST | Gilia stellata | 0–1 | – | ||
| California mustard | GULA4 | Guillenia lasiophylla | 0–1 | – | ||
| New Mexico thistle | CINE | Cirsium neomexicanum | 0–1 | – | ||
| sand pygmyweed | CRCOC | Crassula connata var. connata | 0–1 | – | ||
| cryptantha | CRYPT | Cryptantha | 0–1 | – | ||
| hairy prairie clover | DAMO | Dalea mollis | 0–1 | – | ||
| carelessweed | AMPA | Amaranthus palmeri | 0–1 | – | ||
| whitemargin sandmat | CHAL11 | Chamaesyce albomarginata | 0–1 | – | ||
| Sonoran sandmat | CHMI7 | Chamaesyce micromera | 0–1 | – | ||
| devil's spineflower | CHRI | Chorizanthe rigida | 0–1 | – | ||
| lipfern | CHEIL | Cheilanthes | 0–1 | – | ||
| Chiricahua Mountain sandmat | CHFL3 | Chamaesyce florida | 0–1 | – | ||
| wild cabbage | CAULA | Caulanthus | 0–1 | – | ||
| hoary bowlesia | BOIN3 | Bowlesia incana | 0–1 | – | ||
| California suncup | CACA32 | Camissonia californica | 0–1 | – | ||
| browneyes | CACL4 | Camissonia claviformis | 0–1 | – | ||
| false carrot | YAMI | Yabea microcarpa | 0–1 | – | ||
| bristly scaleseed | SPEC2 | Spermolepis echinata | 0–1 | – | ||
| woollyhead neststraw | STMI2 | Stylocline micropoides | 0–1 | – | ||
| sand fringepod | THCU | Thysanocarpus curvipes | 0–1 | – | ||
|
Shrub/Vine
|
||||||
| 7 | Dominant large shrubs | 11–123 | ||||
| creosote bush | LATRT | Larrea tridentata var. tridentata | 6–112 | – | ||
| ocotillo | FOSP2 | Fouquieria splendens | 0–28 | – | ||
| 8 | Dominant half shrubs | 28–112 | ||||
| desert zinnia | ZIAC | Zinnia acerosa | 22–56 | – | ||
| triangle bur ragweed | AMDE4 | Ambrosia deltoidea | 0–28 | – | ||
| brittlebush | ENFA | Encelia farinosa | 0–22 | – | ||
| littleleaf ratany | KRER | Krameria erecta | 1–22 | – | ||
| rough menodora | MESC | Menodora scabra | 0–22 | – | ||
| fairyduster | CAER | Calliandra eriophylla | 1–17 | – | ||
| white ratany | KRGR | Krameria grayi | 0–11 | – | ||
| button brittlebush | ENFR | Encelia frutescens | 0–11 | – | ||
| whitestem paperflower | PSCO2 | Psilostrophe cooperi | 1–11 | – | ||
| woody crinklemat | TICAC | Tiquilia canescens var. canescens | 0–11 | – | ||
| American threefold | TRCA8 | Trixis californica | 0–6 | – | ||
| Mexican bladdersage | SAME | Salazaria mexicana | 0–6 | – | ||
| pricklyleaf dogweed | THAC | Thymophylla acerosa | 0–6 | – | ||
| burrobush | AMDU2 | Ambrosia dumosa | 0–6 | – | ||
| plains blackfoot | MELE2 | Melampodium leucanthum | 0–6 | – | ||
| broom snakeweed | GUSA2 | Gutierrezia sarothrae | 0–6 | – | ||
| Coulter's brickellbush | BRCO | Brickellia coulteri | 0–2 | – | ||
| threadleaf snakeweed | GUMI | Gutierrezia microcephala | 0–2 | – | ||
| pelotazo | ABIN | Abutilon incanum | 0–2 | – | ||
| 9 | Miscellaneous shrubs | 6–56 | ||||
| jojoba | SICH | Simmondsia chinensis | 0–28 | – | ||
| Parish's goldeneye | VIPA14 | Viguiera parishii | 0–6 | – | ||
| Wright's beebrush | ALWR | Aloysia wrightii | 0–6 | – | ||
| javelina bush | COER5 | Condalia ericoides | 0–6 | – | ||
| knifeleaf condalia | COSP3 | Condalia spathulata | 0–6 | – | ||
| Warnock's snakewood | COWA | Condalia warnockii | 0–6 | – | ||
| Berlandier's wolfberry | LYBE | Lycium berlandieri | 1–6 | – | ||
| mariola | PAIN2 | Parthenium incanum | 0–6 | – | ||
| San Felipe dogweed | ADPO | Adenophyllum porophylloides | 0–2 | – | ||
| Eastern Mojave buckwheat | ERFA2 | Eriogonum fasciculatum | 0–2 | – | ||
| desert yellow fleabane | ERLI | Erigeron linearis | 0–2 | – | ||
| sangre de cristo | JACA2 | Jatropha cardiophylla | 0–2 | – | ||
| slender janusia | JAGR | Janusia gracilis | 0–2 | – | ||
| winterfat | KRLA2 | Krascheninnikovia lanata | 0–2 | – | ||
| common sotol | DAWH2 | Dasylirion wheeleri | 0–2 | – | ||
| fourwing saltbush | ATCA2 | Atriplex canescens | 0–2 | – | ||
| whitethorn acacia | ACCO2 | Acacia constricta | 0–2 | – | ||
| catclaw acacia | ACGR | Acacia greggii | 0–2 | – | ||
| banana yucca | YUBA | Yucca baccata | 0–2 | – | ||
| Joshua tree | YUBR | Yucca brevifolia | 0–2 | – | ||
| turpentinebroom | THMO | Thamnosma montana | 0–2 | – | ||
| toothleaf goldeneye | VIDE3 | Viguiera dentata | 0–2 | – | ||
| soaptree yucca | YUEL | Yucca elata | 0–1 | – | ||
| lotebush | ZIOB | Ziziphus obtusifolia | 0–1 | – | ||
| rayless goldenhead | ACSP | Acamptopappus sphaerocephalus | 0–1 | – | ||
| Nevada jointfir | EPNE | Ephedra nevadensis | 0–1 | – | ||
| water jacket | LYAN | Lycium andersonii | 0–1 | – | ||
| Arizona desert-thorn | LYEX | Lycium exsertum | 0–1 | – | ||
| 10 | Succulents | 6–50 | ||||
| saguaro | CAGI10 | Carnegiea gigantea | 0–22 | – | ||
| cactus apple | OPEN3 | Opuntia engelmannii | 1–11 | – | ||
| purple pricklypear | OPMA8 | Opuntia macrocentra | 0–6 | – | ||
| tulip pricklypear | OPPH | Opuntia phaeacantha | 1–6 | – | ||
| teddybear cholla | CYBI9 | Cylindropuntia bigelovii | 0–6 | – | ||
| walkingstick cactus | CYSP8 | Cylindropuntia spinosior | 1–6 | – | ||
| staghorn cholla | CYVE3 | Cylindropuntia versicolor | 1–6 | – | ||
| jumping cholla | CYFU10 | Cylindropuntia fulgida | 0–3 | – | ||
| ocotillo | FOSP2 | Fouquieria splendens | 0–3 | – | ||
| Christmas cactus | CYLE8 | Cylindropuntia leptocaulis | 0–3 | – | ||
| candy barrelcactus | FEWI | Ferocactus wislizeni | 0–2 | – | ||
| buck-horn cholla | CYAC8 | Cylindropuntia acanthocarpa | 0–2 | – | ||
| Arizona pencil cholla | CYAR14 | Cylindropuntia arbuscula | 0–2 | – | ||
| desert agave | AGDE | Agave deserti | 0–2 | – | ||
| candle cholla | CYKL | Cylindropuntia kleiniae | 0–1 | – | ||
| Engelmann's hedgehog cactus | ECEN | Echinocereus engelmannii | 0–1 | – | ||
| redspine fishhook cactus | ECER2 | Echinomastus erectocentrus | 0–1 | – | ||
| pinkflower hedgehog cactus | ECFA | Echinocereus fasciculatus | 0–1 | – | ||
| Nichol's echinocactus | ECHON | Echinocactus horizonthalonius var. nicholii | 0–1 | – | ||
| spinystar | ESVIV | Escobaria vivipara var. vivipara | 0–1 | – | ||
| Scheer's beehive cactus | COROS | Coryphantha robustispina ssp. scheeri | 0–1 | – | ||
| devil's cholla | GRKU | Grusonia kunzei | 0–1 | – | ||
| Graham's nipple cactus | MAGR9 | Mammillaria grahamii | 0–1 | – | ||
| Thornber's nipple cactus | MATH | Mammillaria thornberi | 0–1 | – | ||
| beavertail pricklypear | OPBA2 | Opuntia basilaris | 0–1 | – | ||
|
Tree
|
||||||
| 11 | Trees | 17–168 | ||||
| yellow paloverde | PAMI5 | Parkinsonia microphylla | 17–112 | – | ||
| velvet mesquite | PRVE | Prosopis velutina | 0–22 | – | ||
| desert ironwood | OLTE | Olneya tesota | 0–22 | – | ||
| crucifixion thorn | CAHO3 | Canotia holacantha | 0–11 | – | ||
| oneseed juniper | JUMO | Juniperus monosperma | 0–6 | – | ||
| blue paloverde | PAFL6 | Parkinsonia florida | 0–6 | – | ||
Interpretations
Animal community
The plant community on this site is suitable for grazing by all classes of cattle at any season. Forage species grow year-round with available moisture. High pH due to lime may tie up soil nutrients and influence grass palatability in the summer growing season. The variety of palatable, evergreen low shrubs in the plant community make it especially valuable for winter grazing.
Water developments are very important to wildlife species on this site. Vegetative cover, topography and forage diversity are good enough for a variety of wildlife species including the large mammals.
Hydrological functions
This site has deep coarse textured soils and even with moderate to steep slopes is not a good producer of runoff.
Recreational uses
Hunting, hiking, horseback riding, camping, photography, birdwatching
Wood products
Limited firewood from mesquite, whitethorn and paloverde for camp fires and branding fires.
Other products
Cactus fruits from saguaro, prickly pear and cholla, jojoba nuts and mesquite beans. Saguaro ribs and ocotillo canes.
Supporting information
Inventory data references
Range 417s include 4 in good condition.
Type locality
| Location 1: Pima County, AZ | |
|---|---|
| Township/Range/Section | T8S R17E S25 |
| General legal description | Tucson FO - Campstool Ranch NE 1/4 sec. 25 |
| Location 2: Pima County, AZ | |
| Township/Range/Section | T10S R2E S3 |
| General legal description | Sells FO - Vekol Mine area NW 1/4 sec. 3 |
| Location 3: Pima County, AZ | |
| Township/Range/Section | T17S R9E S36 |
| General legal description | Palo Alto Ranch, Soldier Well pasture, At transect # 22. |
| Location 4: Pima County, AZ | |
| Township/Range/Section | T18S R14E S30 |
| General legal description | Santa Rita Experimental Range, Gravelly Ridge enclosure. Steep side slopes in southern end of fenced area. Fence built in 1937. |
| Location 5: Cochise County, AZ | |
| Township/Range/Section | T13S R19E S23 |
| General legal description | Cascabel Community Center, Southern aspect (3200 ft. elev.), ungrazed 30 years. |
Other references
The Changing Mile - Revisited. Ray Turner, Robert Webb, University of Arizona Press, Tucson, Arizona, 2003. Photo Station 62
Contributors
C.Michaels
Dan Robinett
Larry D. Ellicott
Rangeland health reference sheet
Interpreting Indicators of Rangeland Health is a qualitative assessment protocol used to determine ecosystem condition based on benchmark characteristics described in the Reference Sheet. A suite of 17 (or more) indicators are typically considered in an assessment. The ecological site(s) representative of an assessment location must be known prior to applying the protocol and must be verified based on soils and climate. Current plant community cannot be used to identify the ecological site.
| Author(s)/participant(s) | Dan Robinett, Don Decker |
|---|---|
| Contact for lead author | NRCS Tucson Area Office |
| Date | 04/29/2003 |
| Approved by | S. Cassady |
| Approval date | |
| Composition (Indicators 10 and 12) based on | Annual Production |
Indicators
-
Number and extent of rills:
None -
Presence of water flow patterns:
Paths are 15 feet apart and sinuous due to terracettes on shrubs and grasses. They are well armored with gravels and cobbles. -
Number and height of erosional pedestals or terracettes:
Pedestals are uncommon on grasses and gravels. Terracettes are common on long-lived shrubs and perennial grasses like bush muhly and black grama. They cover 10-15% of the area. -
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
Bare ground on this site is 10-15% (with 75% gravel and cobble 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):
Herbaceous litter moves only in water flow paths 10-15 feet and is deposited in terracettes at curves in flow paths. Woody litter remains in place under shrub canopies. -
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
No slake test done. Expect ratings of 4-6 under shrub and grass canopies, and 1-3 in openings. High gravel/cobble cover provides good resistance to erosion. -
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
Soil surface is brown gravelly sandy loam 6-8 inches thick over lighter colored, very gravelly, calcareous subsoils. There has been some historic loss of soil surface. -
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Large shrubs (whitethorn #1, mesquite #2, creosote #3 and palo verde) have a 20% canopy cover, shrublike grasses (bush muhly #1, glack grama #2) have a 15% canopy cover, sug-shrubs including desert zinnia, burroweed, snakeweed and paper flower have a %5 canopy cover and succulents like prickley pear, agave and barrel cactus have a 2-3% canopy. -
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
Soil surface (1/2 inch) has a platy structure due to overland water flow and some raindrop impact. There is no subsurface soil compaction. -
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:
large shrubs > shrub-like grasses > sub-shrubs > other perennial grasses > annual forbs and grasses > succulents > perennial forbs > cryptogamsSub-dominant:
Other:
Additional:
-
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
Severe drought last 4 years resulted in 100% mortality on short perennial grasses (tridens and threeawns), 50% mortality on bush muhly, 75% mortality on sub-shrubs and 10-15% mortality on large shrubs. -
Average percent litter cover (%) and depth ( in):
-
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
137 lbs per acre in year with below average rainfall (2002 about 7 inches and 2003 to date 3 inches)500 lbs/ac normal precipitation, 935 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:
Whitethorn acacia, mesquite, burroweed, snakeweed -
Perennial plant reproductive capability:
Impaired by severe drought.
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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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