Natural Resources
Conservation Service
Ecological site R040XB209AZ
Limy Slopes 7"-10" p.z.
Accessed: 11/24/2024
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 40.2 – Middle Sonoran Desert
Elevations range from 1200 to 2000 feet and precipitation averages 7 to 10 inches per year. Vegetation includes saguaro, palo verde, creosotebush, triangle bursage, brittlebush, prickly pear, cholla, desert saltbush, wolfberry bush muhly, threeawns, and big galleta. The soil temperature regime is hyperthermic 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.
Table 1. Dominant plant species
| Tree |
Not specified |
|---|---|
| Shrub |
(1) Ambrosia deltoidea |
| Herbaceous |
(1) Pleuraphis rigida |
Physiographic features
This site occurs on hillslopes and ridgetops. Slopes are from 15 to 45%. Elevations range from 1000 to 2200 feet.
Table 2. Representative physiographic features
| Landforms |
(1)
Hill
(2) Ridge |
|---|---|
| Elevation | 305 – 671 m |
| Slope | 15 – 45% |
Climatic features
Precipitation in the sub-resource area ranges from 7 to 10 inches. Elevations range from 900 to 2050 feet. Winter-summer rainfall ratios range from 40% to 60% in the southern part along the international boundary, to 60% to 40% in the central and northern parts of the sub-resource area. As one moves from east to west in this resource area rains become more unpredictable and variable with Coefficients of Variation of annual rainfall equal to 38% at Florence and 46% at Aguila. Summer rains fall July- September, originate in the Gulf of Mexico, and are convective, usually brief, intense thunderstorms. Summer precipitation is extremely erratic and undependable in this area. Cool season moisture tends to be frontal, originates in the Pacific and Gulf of California, and falls in widespread storms with long duration and low intensity. This is the dependable moisture supply for vegetation in the area. Snow is very rare and usually melts on contact. May-June is the driest time of the year. Humidity is very low.
Winter temperatures are very mild with very few days recording freezing for short periods of time. Summertime temperatures are hot to very hot with many days in June-July exceeding 105 degrees F. Frost-free days range from 280 at stations in major river valleys with cold air drainage to 320 to 350 days at upland stations.
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) | 350 days |
|---|---|
| Freeze-free period (average) | 0 days |
| Precipitation total (average) | 254 mm |
Figure 2. Monthly precipitation range
Figure 3. Monthly average minimum and maximum temperature
Influencing water features
Soil features
These are moderately deep to deep soils formed in very gravelly alluvium of moderate age and from mixed origins. They are very calcareous and have over 35% gravels in the soil profile. Plant-soil moisture relationships are poor.
Soils mapped on this site include: SSA-645 Aguila-Carefree area MU Nickel-39; SSA-651 Central Maricopa County MU, Calciorthids-CA2 & Torriorthents-CA2; SSA-653 Gila Bend-Ajo area MU Ajo-3.
Table 4. Representative soil features
| Surface texture |
(1) Gravelly sandy loam (2) Very gravelly fine sandy loam (3) Extremely gravelly |
|---|---|
| Family particle size |
(1) Loamy |
| Drainage class | Well drained |
| Permeability class | Moderate to moderately rapid |
| Soil depth | 102 – 152 cm |
| Surface fragment cover <=3" | 15 – 65% |
| Surface fragment cover >3" | 1 – 10% |
| Available water capacity (0-101.6cm) |
7.62 – 15.24 cm |
| Calcium carbonate equivalent (0-101.6cm) |
5 – 35% |
| Electrical conductivity (0-101.6cm) |
0 – 2 mmhos/cm |
| Sodium adsorption ratio (0-101.6cm) |
0 |
| Soil reaction (1:1 water) (0-101.6cm) |
7.9 – 8.4 |
| Subsurface fragment volume <=3" (Depth not specified) |
15 – 65% |
| Subsurface fragment volume >3" (Depth not specified) |
1 – 10% |
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
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Ecosystem states
State 1 submodel, plant communities
State 1
Historical Climax Plant Community
Community 1.1
Historical Climax Plant Community
The potential plant community on this site is a mixture of desert shrubs, cacti, perennial grasses and forbs. Annual grasses and forbs make up a small percentage of the potential community. The aspect is shrubland. Perennial grasses and forbs quickly disappear from the plant community with heavy grazing or from drought. Most of the shrubby species on the site are unpalatable and little change has occurred in the composition of these species with past heavy grazing use. A few, cool season, introduced annuals like; red brome, mediterranean grass and london rocket mustard occur on areas of this site and may compete with native annual forbs and grasses. The surfaces of these soils are usually very well protected by covers of gravels, cobbles and caliche fragments. Cryptogam cover is usually very low. Plant populations per acre for major species include; 200 to 300 for creosotebush, 200 to 400 for the ratany-bursage group, and 50 to 100 for cholla species.
Figure 4. 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) |
|---|---|---|---|
| Shrub/Vine | 219 | – | 286 |
| Forb | 34 | – | 50 |
| Grass/Grasslike | 17 | – | 50 |
| Total | 270 | – | 386 |
Additional community tables
Table 6. Community 1.1 plant community composition
| Group | Common name | Symbol | Scientific name | Annual production (kg/hectare) | Foliar cover (%) | |
|---|---|---|---|---|---|---|
|
Grass/Grasslike
|
||||||
| 1 | 17–34 | |||||
| blue threeawn | ARPUN | Aristida purpurea var. nealleyi | 0–11 | – | ||
| bush muhly | MUPO2 | Muhlenbergia porteri | 0–11 | – | ||
| purple threeawn | ARPU9 | Aristida purpurea | 0–6 | – | ||
| big galleta | PLRI3 | Pleuraphis rigida | 0–6 | – | ||
| Parish's threeawn | ARPUP5 | Aristida purpurea var. parishii | 0–2 | – | ||
| Wright's threeawn | ARPUW | Aristida purpurea var. wrightii | 0–2 | – | ||
| spidergrass | ARTE3 | Aristida ternipes | 0–1 | – | ||
| spidergrass | ARTEG | Aristida ternipes var. gentilis | 0–1 | – | ||
| low woollygrass | DAPU7 | Dasyochloa pulchella | 0–1 | – | ||
| Arizona cottontop | DICA8 | Digitaria californica | 0–1 | – | ||
| nineawn pappusgrass | ENDE | Enneapogon desvauxii | 0–1 | – | ||
| plains bristlegrass | SEVU2 | Setaria vulpiseta | 0–1 | – | ||
| sand dropseed | SPCR | Sporobolus cryptandrus | 0–1 | – | ||
| slim tridens | TRMU | Tridens muticus | 0–1 | – | ||
| whiplash pappusgrass | PAVA2 | Pappophorum vaginatum | 0–1 | – | ||
| 2 | 3–17 | |||||
| needle grama | BOAR | Bouteloua aristidoides | 0–6 | – | ||
| sixweeks grama | BOBA2 | Bouteloua barbata | 0–6 | – | ||
| Rothrock's grama | BORO2 | Bouteloua rothrockii | 0–6 | – | ||
| Eastwood fescue | VUMIC | Vulpia microstachys var. ciliata | 0–6 | – | ||
| Pacific fescue | VUMIP | Vulpia microstachys var. pauciflora | 0–6 | – | ||
| Arizona brome | BRAR4 | Bromus arizonicus | 0–1 | – | ||
| feather fingergrass | CHVI4 | Chloris virgata | 0–1 | – | ||
| canyon cupgrass | ERLE7 | Eriochloa lemmonii | 0–1 | – | ||
| desert lovegrass | ERPEM | Eragrostis pectinacea var. miserrima | 0–1 | – | ||
| tufted lovegrass | ERPEP2 | Eragrostis pectinacea var. pectinacea | 0–1 | – | ||
| Mexican sprangletop | LEFUU | Leptochloa fusca ssp. uninervia | 0–1 | – | ||
| mucronate sprangletop | LEPA6 | Leptochloa panicea | 0–1 | – | ||
| delicate muhly | MUFR | Muhlenbergia fragilis | 0–1 | – | ||
| littleseed muhly | MUMI | Muhlenbergia microsperma | 0–1 | – | ||
| Bigelow's bluegrass | POBI | Poa bigelovii | 0–1 | – | ||
| Arizona signalgrass | URAR | Urochloa arizonica | 0–1 | – | ||
| 3 | 3–17 | |||||
| Alga | 2ALGA | Alga | 0–11 | – | ||
| Fungus | 2FUNGI | Fungus | 0–2 | – | ||
| Lichen | 2LICHN | Lichen | 0–2 | – | ||
| Moss | 2MOSS | Moss | 0–2 | – | ||
| strigose bird's-foot trefoil | LOSTT | Lotus strigosus var. tomentellus | 0–1 | – | ||
|
Forb
|
||||||
| 4 | 17–34 | |||||
| desert globemallow | SPAM2 | Sphaeralcea ambigua | 6–11 | – | ||
| desert trumpet | ERIN4 | Eriogonum inflatum | 2–6 | – | ||
| Parry's false prairie-clover | MAPA7 | Marina parryi | 0–2 | – | ||
| lacy tansyaster | MAPIP4 | Machaeranthera pinnatifida ssp. pinnatifida var. pinnatifida | 0–2 | – | ||
| rough menodora | MESC | Menodora scabra | 0–1 | – | ||
| evening primrose | OENOT | Oenothera | 0–1 | – | ||
| slender poreleaf | POGR5 | Porophyllum gracile | 0–1 | – | ||
| Coues' cassia | SECO10 | Senna covesii | 0–1 | – | ||
| California fagonbush | FALA | Fagonia laevis | 0–1 | – | ||
| paleface | HIDE | Hibiscus denudatus | 0–1 | – | ||
| slender janusia | JAGR | Janusia gracilis | 0–1 | – | ||
| brownplume wirelettuce | STPA4 | Stephanomeria pauciflora | 0–1 | – | ||
| dwarf desertpeony | ACNA2 | Acourtia nana | 0–1 | – | ||
| brownfoot | ACWR5 | Acourtia wrightii | 0–1 | – | ||
| poreleaf dogweed | ADPO2 | Adenophyllum porophyllum | 0–1 | – | ||
| trailing windmills | ALIN | Allionia incarnata | 0–1 | – | ||
| narrowleaf silverbush | ARLA12 | Argythamnia lanceolata | 0–1 | – | ||
| New Mexico silverbush | ARNE2 | Argythamnia neomexicana | 0–1 | – | ||
| rush milkweed | ASSU | Asclepias subulata | 0–1 | – | ||
| desert marigold | BAMU | Baileya multiradiata | 0–1 | – | ||
| whitemargin sandmat | CHAL11 | Chamaesyce albomarginata | 0–1 | – | ||
| desert larkspur | DEPA | Delphinium parishii | 0–1 | – | ||
| tall mountain larkspur | DESC | Delphinium scaposum | 0–1 | – | ||
| bluedicks | DICA14 | Dichelostemma capitatum | 0–1 | – | ||
| 5 | 3–17 | |||||
| sand pygmyweed | CRCO34 | Crassula connata | 0–3 | – | ||
| combseed | PECTO | Pectocarya | 0–3 | – | ||
| woolly tidestromia | TILA2 | Tidestromia lanuginosa | 0–3 | – | ||
| coastal bird's-foot trefoil | LOSAB | Lotus salsuginosus var. brevivexillus | 0–2 | – | ||
| strigose bird's-foot trefoil | LOSTT | Lotus strigosus var. tomentellus | 0–2 | – | ||
| cryptantha | CRYPT | Cryptantha | 0–2 | – | ||
| hairy prairie clover | DAMO | Dalea mollis | 0–1 | – | ||
| American wild carrot | DAPU3 | Daucus pusillus | 0–1 | – | ||
| western tansymustard | DEPI | Descurainia pinnata | 0–1 | – | ||
| flatcrown buckwheat | ERDE6 | Eriogonum deflexum | 0–1 | – | ||
| miniature woollystar | ERDI2 | Eriastrum diffusum | 0–1 | – | ||
| erigenia | ERIGE | Erigenia | 0–1 | – | ||
| buckwheat | ERIOG | Eriogonum | 0–1 | – | ||
| Texas stork's bill | ERTE13 | Erodium texanum | 0–1 | – | ||
| California poppy | ESCAM | Eschscholzia californica ssp. mexicana | 0–1 | – | ||
| pygmy poppy | ESMI | Eschscholzia minutiflora | 0–1 | – | ||
| gilia | GILIA | Gilia | 0–1 | – | ||
| Gordon's bladderpod | LEGO | Lesquerella gordonii | 0–1 | – | ||
| shaggyfruit pepperweed | LELA | Lepidium lasiocarpum | 0–1 | – | ||
| foothill deervetch | LOHU2 | Lotus humistratus | 0–1 | – | ||
| common fiddleneck | AMMEI2 | Amsinckia menziesii var. intermedia | 0–1 | – | ||
| bristly fiddleneck | AMTE3 | Amsinckia tessellata | 0–1 | – | ||
| milkvetch | ASTRA | Astragalus | 0–1 | – | ||
| Coulter's spiderling | BOCO2 | Boerhavia coulteri | 0–1 | – | ||
| hoary bowlesia | BOIN3 | Bowlesia incana | 0–1 | – | ||
| California suncup | CACA32 | Camissonia californica | 0–1 | – | ||
| exserted Indian paintbrush | CAEXE | Castilleja exserta ssp. exserta | 0–1 | – | ||
| yellow tackstem | CAPA7 | Calycoseris parryi | 0–1 | – | ||
| white tackstem | CAWR | Calycoseris wrightii | 0–1 | – | ||
| brittle spineflower | CHBR | Chorizanthe brevicornu | 0–1 | – | ||
| pebble pincushion | CHCA | Chaenactis carphoclinia | 0–1 | – | ||
| hyssopleaf sandmat | CHHY3 | Chamaesyce hyssopifolia | 0–1 | – | ||
| devil's spineflower | CHRI | Chorizanthe rigida | 0–1 | – | ||
| Esteve's pincushion | CHST | Chaenactis stevioides | 0–1 | – | ||
| New Mexico thistle | CINE | Cirsium neomexicanum | 0–1 | – | ||
| Arizona lupine | LUAR4 | Lupinus arizonicus | 0–1 | – | ||
| Coulter's lupine | LUSP2 | Lupinus sparsiflorus | 0–1 | – | ||
| blazingstar | MENTZ | Mentzelia | 0–1 | – | ||
| bristly nama | NAHI | Nama hispidum | 0–1 | – | ||
| glandular threadplant | NEGL | Nemacladus glanduliferus | 0–1 | – | ||
| Florida pellitory | PAFL3 | Parietaria floridana | 0–1 | – | ||
| manybristle chinchweed | PEPA2 | Pectis papposa | 0–1 | – | ||
| phacelia | PHACE | Phacelia | 0–1 | – | ||
| desert Indianwheat | PLOV | Plantago ovata | 0–1 | – | ||
| New Mexico plumeseed | RANE | Rafinesquia neomexicana | 0–1 | – | ||
| chia | SACO6 | Salvia columbariae | 0–1 | – | ||
| sleepy silene | SIAN2 | Silene antirrhina | 0–1 | – | ||
| Coulter's globemallow | SPCO2 | Sphaeralcea coulteri | 0–1 | – | ||
| woollyhead neststraw | STMI2 | Stylocline micropoides | 0–1 | – | ||
|
Shrub/Vine
|
||||||
| 6 | 101–151 | |||||
| creosote bush | LATR2 | Larrea tridentata | 101–151 | – | ||
| 7 | 34–67 | |||||
| triangle bur ragweed | AMDE4 | Ambrosia deltoidea | 17–34 | – | ||
| burrobush | AMDU2 | Ambrosia dumosa | 17–34 | – | ||
| brittlebush | ENFA | Encelia farinosa | 0–6 | – | ||
| 8 | 17–34 | |||||
| white ratany | KRGR | Krameria grayi | 11–22 | – | ||
| littleleaf ratany | KRER | Krameria erecta | 6–11 | – | ||
| 9 | 17–34 | |||||
| yellow paloverde | PAMI5 | Parkinsonia microphylla | 0–6 | – | ||
| desert ironwood | OLTE | Olneya tesota | 0–3 | – | ||
| ocotillo | FOSP2 | Fouquieria splendens | 0–2 | – | ||
| desert lavender | HYEM | Hyptis emoryi | 0–1 | – | ||
| sangre de cristo | JACA2 | Jatropha cardiophylla | 0–1 | – | ||
| crown of thorns | KOSP | Koeberlinia spinosa | 0–1 | – | ||
| water jacket | LYAN | Lycium andersonii | 0–1 | – | ||
| Arizona desert-thorn | LYEX | Lycium exsertum | 0–1 | – | ||
| desert wolfberry | LYMA | Lycium macrodon | 0–1 | – | ||
| velvet mesquite | PRVE | Prosopis velutina | 0–1 | – | ||
| whitestem paperflower | PSCO2 | Psilostrophe cooperi | 0–1 | – | ||
| dwarf saltwort | SABI | Salicornia bigelovii | 0–1 | – | ||
| Mexican bladdersage | SAME | Salazaria mexicana | 0–1 | – | ||
| jojoba | SICH | Simmondsia chinensis | 0–1 | – | ||
| woody crinklemat | TICAC | Tiquilia canescens var. canescens | 0–1 | – | ||
| American threefold | TRCA8 | Trixis californica | 0–1 | – | ||
| Parish's goldeneye | VIPA14 | Viguiera parishii | 0–1 | – | ||
| desert zinnia | ZIAC | Zinnia acerosa | 0–1 | – | ||
| lotebush | ZIOB | Ziziphus obtusifolia | 0–1 | – | ||
| whitethorn acacia | ACCO2 | Acacia constricta | 0–1 | – | ||
| catclaw acacia | ACGR | Acacia greggii | 0–1 | – | ||
| rayless goldenhead | ACSP | Acamptopappus sphaerocephalus | 0–1 | – | ||
| Coulter's brickellbush | BRCO | Brickellia coulteri | 0–1 | – | ||
| button brittlebush | ENFR | Encelia frutescens | 0–1 | – | ||
| Nevada jointfir | EPNE | Ephedra nevadensis | 0–1 | – | ||
| 10 | 17–34 | |||||
| senita cactus | PASC14 | Pachycereus schottii | 0–2 | – | ||
| organpipe cactus | STTH3 | Stenocereus thurberi | 0–2 | – | ||
| beavertail pricklypear | OPBA2 | Opuntia basilaris | 0–1 | – | ||
| Engelmann's hedgehog cactus | ECEN | Echinocereus engelmannii | 0–1 | – | ||
| Leconte's barrel cactus | FECYL | Ferocactus cylindraceus var. lecontei | 0–1 | – | ||
| candy barrelcactus | FEWI | Ferocactus wislizeni | 0–1 | – | ||
| common fishhook cactus | MATE4 | Mammillaria tetrancistra | 0–1 | – | ||
Interpretations
Animal community
This site produces small amounts of herbaceous and shrubby forage for year-round use. Even in wet winters the production of cool season annuals is low and provides for little additional carrying capacity.
This site is home to a variety of desert mammals, birds and reptiles. Though cover is lacking, topography provides enough security for the site to support the larger desert mammals. Desert tortoises den in pockets and caverns under caliche outcrops on steep slopes and along drainage ways.
Other information
T&E: Antilocapra Americanc sonoriensis
(Sonoran pronghorn)
Leptonycteris curasoae yerbe buena
(Lesser long-nosed bat)
Supporting information
Type locality
| Location 1: Maricopa County, AZ | |
|---|---|
| Township/Range/Section | T7S R2W S2 |
| General legal description | Buckeye FO - Sand Tank Mountains |
| Location 2: Maricopa County, AZ | |
| Township/Range/Section | T1N R8E S22 |
| General legal description | Chandler FO - Apache Junction |
| Location 3: Pima County, AZ | |
| Township/Range/Section | T13S R8E S20 |
| General legal description | Sells FO - Shuck Toak Dist., Aguirre Valley |
| Location 4: Pima County, AZ | |
| Township/Range/Section | T15S R7W S20 |
| General legal description | Tucson FO - Organ Pipe National Monument |
Contributors
Dan Robinett
Dan Robinett, J. Norris
Larry D. Ellicott
Steve Barker
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) | Dave Womack, Dan Robinett, Emilio Carrillo |
|---|---|
| Contact for lead author | NRCS Tucson Area Office |
| Date | 12/28/2005 |
| Approved by | S. Cassady |
| Approval date | |
| Composition (Indicators 10 and 12) based on | Annual Production |
Indicators
-
Number and extent of rills:
Rills are common and continuous in absence of high gravel cover. -
Presence of water flow patterns:
Water flow patterns are common, continuous and occupy 15-20% of area. -
Number and height of erosional pedestals or terracettes:
Erosional pedestals not present on most perennial plants. -
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
10-30% (low values in high gravel cover areas and/or in El Nino years) -
Number of gullies and erosion associated with gullies:
noen -
Extent of wind scoured, blowouts and/or depositional areas:
none -
Amount of litter movement (describe size and distance expected to travel):
Woody litter mostly stays under plant canopy; herbaceous litter can travel long distances. -
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Soil surface resistance to erosion is good under shrub canopies to moderate in interspaces due to crusts formed by raindrop impact. -
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
weak thin platy to granular; A horizon is 4 inches. Accumulated pedestals on most perennial plants, not so much so in high gravel cover areas, 2-5 inches high. -
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Cover estimated as: canopy 5-10%, Basal 1%; 80-85% shrubs, 5-10% halfshrubs, 5-10% succulents. Cover is well dispersed throughout the site. -
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
none -
Functional/Structural Groups (list in order of descending dominance by above-ground annual-production or live foliar cover using symbols: >>, >, = to indicate much greater than, greater than, and equal to):
Dominant:
shrubs > halfshrubs > succulents > trees > annual grasses & forbs > perennial forbs = perennial grasses (note: in El Nino years annual frobs and grasses are #1 in above ground weight.)Sub-dominant:
Other:
Additional:
-
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
0-50% canopy mortality -
Average percent litter cover (%) and depth ( in):
-
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
250 lbs/ac unfavorable precipitation, 350 lbs/ac normal precipitation, 500 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:
Sahara mustard, schismus, filaree -
Perennial plant reproductive capability:
Not impaired for shrubs, drought impaired for perennial grasses and forbs.
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