Natural Resources
Conservation Service
Ecological site R041XC301AZ
Basalt Hills 12-16" 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): 041X–Madrean Archipelago
AZ 41.3 – Chihuahuan – Sonoran Semidesert Grasslands
Elevations range from 3200 to 5000 feet and precipitation ranges from 12 to 16 inches per year. Vegetation includes mesquite, catclaw acacia, netleaf hackberry, palo verde, false mesquite, range ratany, fourwing saltbush, tarbush, littleleaf sumac, sideoats grama, black grama, plains lovegrass, cane beardgrass, tobosa, vine mesquite, threeawns, Arizona cottontop and bush muhly. The soil temperature regime is thermic and the soil moisture regime is ustic 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 |
Not specified |
| Herbaceous |
Not specified |
Physiographic features
This site occurs on hillslopes and ridgetops. Slope aspect is site differentiating at elevations near land resource area boundaries.
Table 2. Representative physiographic features
| Landforms |
(1)
Hill
(2) Ridge |
|---|---|
| Flooding frequency | None |
| Ponding frequency | None |
| Elevation | 1,158 – 1,676 m |
| Slope | 15 – 70% |
Climatic features
Precipitation in this common resource area ranges from 12-16 inches yearly in the eastern part with elevations from 3600-5000 feet, and 13-17 inches in the western part where elevations are 3300-4500 feet. Winter-Summer rainfall ratios are 40-60% in the west and 30-70% in the east. Summer rains fall July-September, originate in the Gulf of Mexico and are convective, usually brief, intense thunderstorms. Cool season moisture tends to be frontal, originate in the Pacific and Gulf of California, and falls in widespread storms with long durarion and low density. Snow rarely lasts more than one day. May and June are the driest months of the year. Humidity is generally very low.
Temperatures are mild. Freezing temperatures are common at night from December-April; however temperatures during the day are frequently above 50 F. Occasionally in December-February, brief 0 F temperatures may be experienced some nights. During June, July and August, some days may exceed 100 F.
Cool season plants start growth in early spring and mature in early summer. Warm season plants take advantage of summer rains and are growing and nutritions July-September. Warm season grasses may remain green throughout the year.
Table 3. Representative climatic features
| Frost-free period (average) | 220 days |
|---|---|
| Freeze-free period (average) | 0 days |
| Precipitation total (average) | 406 mm |
Figure 2. Monthly precipitation range
Figure 3. Monthly average minimum and maximum temperature
Influencing water features
Soil features
These are shallow soils formed in slope alluvium of mixed basic igneous and cargonatic minerology. Soils are calcareous loams and clay loams with a complete cover of basalt cobbles and stones. Large areas of talus or rock slides occur intermingled with soil areas. Plant-soil moisture relationships are fair.
Soils mapped on this site include: SSA-664 San Simon area MU's 5 & 25 Graham; SSA-669 Pima county Eastern part MU 32 Graham; SSA-671 Cochise county Douglas-Tombstone part MU's 16 Boss, Krentz & Paramore, 75 Graham & Lampshire.
Table 4. Representative soil features
| Parent material |
(1)
Slope alluvium
–
basalt
|
|---|---|
| Surface texture |
(1) Loam (2) Clay loam |
| Permeability class | Moderate |
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 each group. Divide the resulting total by the total normal year production shown in the plant community description. If the rainfall has ben 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
Historic Climax Plant Community
Community 1.1
Historic Climax Plant Community
The potential plant community on this site is dominated by warm season perennial grasses. Shrubs are well represented on the site, as well as perennial and annual forbs. The major grass species tend to be well dispersed througout the plant community. Shrubs are concentrated at the edge of outcrops and along talus slides. The aspect is dotted grassland.
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) |
|---|---|---|---|
| Grass/Grasslike | 605 | – | 706 |
| Shrub/Vine | 202 | – | 303 |
| Forb | 101 | – | 151 |
| Total | 908 | – | 1160 |
Figure 5. Plant community growth curve (percent production by month). AZ4131, 41.3 12-16" p.z. hill sites. Growth begins in the spring, semi-dormancy occurs during the June drought, most growth occurs during the summer rainy season..
| 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 | 0 | 5 | 10 | 10 | 0 | 30 | 30 | 10 | 5 | 0 | 0 |
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 | 202–303 | |||||
| black grama | BOER4 | Bouteloua eriopoda | 202–303 | – | ||
| 2 | 151–252 | |||||
| sideoats grama | BOCU | Bouteloua curtipendula | 151–252 | – | ||
| 3 | 303 | |||||
| cane bluestem | BOBA3 | Bothriochloa barbinodis | 303 | – | ||
| Arizona cottontop | DICA8 | Digitaria californica | 303 | – | ||
| bush muhly | MUPO2 | Muhlenbergia porteri | 303 | – | ||
| 4 | 50–101 | |||||
| Orcutt's threeawn | ARSCO | Aristida schiedeana var. orcuttiana | 50–101 | – | ||
| spidergrass | ARTE3 | Aristida ternipes | 50–101 | – | ||
| spidergrass | ARTEG | Aristida ternipes var. gentilis | 50–101 | – | ||
| plains lovegrass | ERIN | Eragrostis intermedia | 50–101 | – | ||
| tanglehead | HECO10 | Heteropogon contortus | 50–101 | – | ||
| green sprangletop | LEDU | Leptochloa dubia | 50–101 | – | ||
| tobosagrass | PLMU3 | Pleuraphis mutica | 50–101 | – | ||
| plains bristlegrass | SEVU2 | Setaria vulpiseta | 50–101 | – | ||
| spike dropseed | SPCO4 | Sporobolus contractus | 50–101 | – | ||
| sand dropseed | SPCR | Sporobolus cryptandrus | 50–101 | – | ||
| 5 | 10–50 | |||||
| sixweeks threeawn | ARAD | Aristida adscensionis | 10–50 | – | ||
| needle grama | BOAR | Bouteloua aristidoides | 10–50 | – | ||
| sixweeks grama | BOBA2 | Bouteloua barbata | 10–50 | – | ||
| Arizona brome | BRAR4 | Bromus arizonicus | 10–50 | – | ||
| feather fingergrass | CHVI4 | Chloris virgata | 10–50 | – | ||
| desert lovegrass | ERPEM | Eragrostis pectinacea var. miserrima | 10–50 | – | ||
| little barley | HOPU | Hordeum pusillum | 10–50 | – | ||
| Mexican sprangletop | LEFUU | Leptochloa fusca ssp. uninervia | 10–50 | – | ||
| mucronate sprangletop | LEPA6 | Leptochloa panicea | 10–50 | – | ||
| Arizona signalgrass | URAR | Urochloa arizonica | 10–50 | – | ||
| sixweeks fescue | VUOC | Vulpia octoflora | 10–50 | – | ||
| 6 | 10–50 | |||||
| low woollygrass | DAPU7 | Dasyochloa pulchella | 10–50 | – | ||
| nineawn pappusgrass | ENDE | Enneapogon desvauxii | 10–50 | – | ||
| Palmer's crinklemat | TIPA | Tiquilia palmeri | 10–50 | – | ||
| slim tridens | TRMU | Tridens muticus | 10–50 | – | ||
| 7 | 10–50 | |||||
| sprucetop grama | BOCH | Bouteloua chondrosioides | 10–50 | – | ||
| blue grama | BOGR2 | Bouteloua gracilis | 10–50 | – | ||
| hairy grama | BOHI2 | Bouteloua hirsuta | 10–50 | – | ||
| purple grama | BORA | Bouteloua radicosa | 10–50 | – | ||
| slender grama | BORE2 | Bouteloua repens | 10–50 | – | ||
| curly-mesquite | HIBE | Hilaria belangeri | 10–50 | – | ||
| common wolfstail | LYPH | Lycurus phleoides | 10–50 | – | ||
| Hall's panicgrass | PAHA | Panicum hallii | 10–50 | – | ||
| vine mesquite | PAOB | Panicum obtusum | 10–50 | – | ||
| 8 | 10–50 | |||||
| poverty threeawn | ARDI5 | Aristida divaricata | 10–50 | – | ||
| Havard's threeawn | ARHA3 | Aristida havardii | 10–50 | – | ||
| Wooton's threeawn | ARPA9 | Aristida pansa | 10–50 | – | ||
| purple threeawn | ARPU9 | Aristida purpurea | 10–50 | – | ||
| blue threeawn | ARPUN | Aristida purpurea var. nealleyi | 10–50 | – | ||
| sedge | CAREX | Carex | 10–50 | – | ||
| squirreltail | ELELE | Elymus elymoides ssp. elymoides | 10–50 | – | ||
| bullgrass | MUEM | Muhlenbergia emersleyi | 10–50 | – | ||
| creeping muhly | MURE | Muhlenbergia repens | 10–50 | – | ||
| slender muhly | MUTE4 | Muhlenbergia tenuifolia | 10–50 | – | ||
| Texas bluestem | SCCI2 | Schizachyrium cirratum | 10–50 | – | ||
| slim tridens | TRMUE | Tridens muticus var. elongatus | 10–50 | – | ||
|
Forb
|
||||||
| 9 | 50–101 | |||||
| dwarf Indian mallow | ABPA3 | Abutilon parvulum | 50–101 | – | ||
| San Felipe dogweed | ADPO | Adenophyllum porophylloides | 50–101 | – | ||
| trailing windmills | ALIN | Allionia incarnata | 50–101 | – | ||
| weakleaf bur ragweed | AMCO3 | Ambrosia confertiflora | 50–101 | – | ||
| anoda | ANODA | Anoda | 50–101 | – | ||
| desert marigold | BAMU | Baileya multiradiata | 50–101 | – | ||
| spreading fleabane | ERDI4 | Erigeron divergens | 50–101 | – | ||
| Arizona snakecotton | FRAR2 | Froelichia arizonica | 50–101 | – | ||
| haplopappus | HAPLO11 | Haplopappus | 50–101 | – | ||
| slender janusia | JAGR | Janusia gracilis | 50–101 | – | ||
| tree tobacco | NIGL | Nicotiana glauca | 50–101 | – | ||
| Wright's cudweed | PSCAC2 | Pseudognaphalium canescens ssp. canescens | 50–101 | – | ||
| twinleaf senna | SEBA3 | Senna bauhinioides | 50–101 | – | ||
| spreading fanpetals | SIAB | Sida abutifolia | 50–101 | – | ||
| desert globemallow | SPAM2 | Sphaeralcea ambigua | 50–101 | – | ||
| brownplume wirelettuce | STPA4 | Stephanomeria pauciflora | 50–101 | – | ||
| 10 | 50 | |||||
| carelessweed | AMPA | Amaranthus palmeri | 50 | – | ||
| pioneer rockcress | ARPL | Arabis platysperma | 50 | – | ||
| clasping milkweed | ASAM | Asclepias amplexicaulis | 50 | – | ||
| aster | ASTER | Aster | 50 | – | ||
| milkvetch | ASTRA | Astragalus | 50 | – | ||
| hairyseed bahia | BAAB | Bahia absinthifolia | 50 | – | ||
| spiderling | BOERH2 | Boerhavia | 50 | – | ||
| hoary bowlesia | BOIN3 | Bowlesia incana | 50 | – | ||
| lipfern | CHEIL | Cheilanthes | 50 | – | ||
| goosefoot | CHENO | Chenopodium | 50 | – | ||
| fingerleaf gourd | CUDI | Cucurbita digitata | 50 | – | ||
| American wild carrot | DAPU3 | Daucus pusillus | 50 | – | ||
| western tansymustard | DEPI | Descurainia pinnata | 50 | – | ||
| fetid marigold | DYPA | Dyssodia papposa | 50 | – | ||
| flatcrown buckwheat | ERDE6 | Eriogonum deflexum | 50 | – | ||
| spurge | EUPHO | Euphorbia | 50 | – | ||
| Indian rushpea | HOGL2 | Hoffmannseggia glauca | 50 | – | ||
| redstar | IPCO3 | Ipomoea coccinea | 50 | – | ||
| ragged nettlespurge | JAMA | Jatropha macrorhiza | 50 | – | ||
| prickly lettuce | LASE | Lactuca serriola | 50 | – | ||
| shaggyfruit pepperweed | LELA | Lepidium lasiocarpum | 50 | – | ||
| intermediate pepperweed | LEVIM | Lepidium virginicum var. medium | 50 | – | ||
| common deerweed | LOSC2 | Lotus scoparius | 50 | – | ||
| blazingstar | MENTZ | Mentzelia | 50 | – | ||
| minerslettuce | MONTI | Montia | 50 | – | ||
| cloak fern | NOTHO | Notholaena | 50 | – | ||
| owl's-clover | ORTHO | Orthocarpus | 50 | – | ||
| Florida pellitory | PAFL3 | Parietaria floridana | 50 | – | ||
| chinchweed | PECTI | Pectis | 50 | – | ||
| cliffbrake | PELLA | Pellaea | 50 | – | ||
| Parry's beardtongue | PEPA24 | Penstemon parryi | 50 | – | ||
| Nine Mile Canyon phacelia | PHNO | Phacelia novenmillensis | 50 | – | ||
| desert Indianwheat | PLOV | Plantago ovata | 50 | – | ||
| silverleaf nightshade | SOEL | Solanum elaeagnifolium | 50 | – | ||
| pricklyleaf dogweed | THAC | Thymophylla acerosa | 50 | – | ||
| rue of the mountains | THTE2 | Thamnosma texana | 50 | – | ||
| woolly tidestromia | TILA2 | Tidestromia lanuginosa | 50 | – | ||
| catnip noseburn | TRNE | Tragia nepetifolia | 50 | – | ||
| verbena | VEPO4 | Verbena polystachya | 50 | – | ||
| American vetch | VIAM | Vicia americana | 50 | – | ||
| garden vetch | VISAN2 | Vicia sativa ssp. nigra | 50 | – | ||
|
Shrub/Vine
|
||||||
| 11 | 50–101 | |||||
| whitethorn acacia | ACCO2 | Acacia constricta | 50–101 | – | ||
| Wright's beebrush | ALWR | Aloysia wrightii | 50–101 | – | ||
| Palmer's cock's comb | CEPA5 | Celosia palmeri | 50–101 | – | ||
| creosote bush | LATRT | Larrea tridentata var. tridentata | 50–101 | – | ||
| 12 | 50–101 | |||||
| pelotazo | ABIN | Abutilon incanum | 50–101 | – | ||
| fourwing saltbush | ATCA2 | Atriplex canescens | 50–101 | – | ||
| yerba de pasmo | BAPT | Baccharis pteronioides | 50–101 | – | ||
| resinleaf brickellbush | BRBA2 | Brickellia baccharidea | 50–101 | – | ||
| fairyduster | CAER | Calliandra eriophylla | 50–101 | – | ||
| Cooley's bundleflower | DECO2 | Desmanthus cooleyi | 50–101 | – | ||
| ookow | DICO19 | Dichelostemma congestum | 50–101 | – | ||
| longleaf jointfir | EPTR | Ephedra trifurca | 50–101 | – | ||
| bastardsage | ERWR | Eriogonum wrightii | 50–101 | – | ||
| rock sage | SAPI2 | Salvia pinguifolia | 50–101 | – | ||
| American threefold | TRCA8 | Trixis californica | 50–101 | – | ||
| desert zinnia | ZIAC | Zinnia acerosa | 50–101 | – | ||
| 13 | 10–50 | |||||
| pelotazo | ABIN | Abutilon incanum | 10–50 | – | ||
| prairie acacia | ACAN | Acacia angustissima | 10–50 | – | ||
| catclaw acacia | ACGR | Acacia greggii | 10–50 | – | ||
| milfoil wattle | ACMI | Acacia millefolia | 10–50 | – | ||
| netleaf hackberry | CELAR | Celtis laevigata var. reticulata | 10–50 | – | ||
| oneseed juniper | JUMO | Juniperus monosperma | 10–50 | – | ||
| desert-thorn | LYCIU | Lycium | 10–50 | – | ||
| mariola | PAIN2 | Parthenium incanum | 10–50 | – | ||
| honey mesquite | PRGLG | Prosopis glandulosa var. glandulosa | 10–50 | – | ||
| littleleaf sumac | RHMI3 | Rhus microphylla | 10–50 | – | ||
| Wright's mock buckthorn | SAWR | Sageretia wrightii | 10–50 | – | ||
| woody crinklemat | TICAC | Tiquilia canescens var. canescens | 10–50 | – | ||
| lotebush | ZIOB | Ziziphus obtusifolia | 10–50 | – | ||
| 14 | 10–20 | |||||
| desertbroom | BASA2 | Baccharis sarothroides | 10–20 | – | ||
| threadleaf snakeweed | GUMI | Gutierrezia microcephala | 10–20 | – | ||
| broom snakeweed | GUSA2 | Gutierrezia sarothrae | 10–20 | – | ||
| burroweed | ISTE2 | Isocoma tenuisecta | 10–20 | – | ||
| alyssumleaf phlox | PHALA4 | Phlox alyssifolia ssp. abdita | 10–20 | – | ||
| Douglas' spikemoss | SEDO | Selaginella douglasii | 10–20 | – | ||
| 15 | 10–50 | |||||
| desert agave | AGDE | Agave deserti | 10–50 | – | ||
| Bill Williams Mountain giant hyssop | AGPA | Agastache pallidiflora | 10–50 | – | ||
| common sotol | DAWH2 | Dasylirion wheeleri | 10–50 | – | ||
| candy barrelcactus | FEWI | Ferocactus wislizeni | 10–50 | – | ||
| ocotillo | FOSP2 | Fouquieria splendens | 10–50 | – | ||
| globe cactus | MAMMI | Mammillaria | 10–50 | – | ||
| sacahuista | NOMI | Nolina microcarpa | 10–50 | – | ||
| beavertail pricklypear | OPBA2 | Opuntia basilaris | 10–50 | – | ||
| limestone adderstongue | OPEN | Ophioglossum engelmannii | 10–50 | – | ||
| banana yucca | YUBA | Yucca baccata | 10–50 | – | ||
| Schott's yucca | YUSC | Yucca ×schottii | 10–50 | – | ||
Interpretations
Animal community
This site produces fair quality herbaceous forage. High soil pH is somewhat offset by inherent soil fertility. The site is not well suited to summertime grazing by cows with calves. Mother cow pairs will only use 300-400 feet, up or down in elevation, from water in the summer. Dry cows will use double that distance in the cool season. Yearling cattle make good use of the site in any season. Slope aspect affects both the intensity of use and seasonal use patterns. North-south trending slopes will be used fairly well even in summer, as the wets slope is shady in the morning and the east slope is shady in the afternoon. South facing slopes are used heavily in the winter-spring due to warmth from cold weather and early greenup of warm season grasses. North facing slopes, bieng shady and cooler, are used in the summer, and especially in the fall as the perennial grasses stay greener longer into the cool season. Very dar colored rock and soil surfaces cause early soil warming and, consequently, earlier greenup of warm season perennial grasses in the spring. Seep and canyon water is available in most winters from December-February.
Water developments are very important to wildlife on this site. The site is home to a wide variety of wildlife species due to the diversity of food, cover and edge.
Supporting information
Type locality
| Location 1: Cochise County, AZ | |
|---|---|
| Township/Range/Section | T23S R29E S29 |
| General legal description | Rocker M Ranch |
| Location 2: Pima County, AZ | |
| Township/Range/Section | T18S R10E S28 |
| General legal description | Batamote Ranch |
| Location 3: Cochise County, AZ | |
| Township/Range/Section | T20S R24E S7 |
| General legal description | Cowan Ranch |
Contributors
Dan Robinett
Larry D. Ellicott
Steve Barker
Unknown
Unknwon
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 | USDA-NRCS Tucson Area Office |
| Date | 02/25/2005 |
| Approved by | Byron Lambeth |
| Approval date | |
| Composition (Indicators 10 and 12) based on | Annual Production |
Indicators
-
Number and extent of rills:
None present on this site. -
Presence of water flow patterns:
Uncommon; probably cover no more than 10% of area; discontinuous; very short, usually
less than 1 foot in length; broken primarily by high rock and gravel cover. -
Number and height of erosional pedestals or terracettes:
Pedestals are uncommon on perennial grass and shrubs; Limited
soil material not conducive to forming continuous stands of plants that promote terracettes; high rock cover forms limited
natural terracettes. -
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
Estimated at 0-5%. -
Number of gullies and erosion associated with gullies:
None present on this site. -
Extent of wind scoured, blowouts and/or depositional areas:
None present on this site. -
Amount of litter movement (describe size and distance expected to travel):
All litter size classes staying in place. -
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 values of 1-2 in canopy interspaces, and 4 - 6 under plant canopies. -
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
Weak coarse granular; Color is 10YR5/4 Dry, 10YR3/2 Moist; thickness to 3 inches. -
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Cover estimated as: Canopy 20-30%, Basal 5%, Litter 45-55%, and Gravel 30%; 10% of canopy cover is perennial mid grasses, 25% short grasses, 5% perennial forbs, 45% shrubs and 10% subshrubs. Cover is well dispersed throughout site. -
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
None present on this site. -
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:
Perennial grass = shrubsSub-dominant:
annual grasses & forbs > subshrubs > succulents = perennial forbsOther:
Additional:
-
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
2-3% of perennial grass plants have died with skeletons still present; 50% of basal cover of perennial grasses has been lost in recent prolonged drought. -
Average percent litter cover (%) and depth ( in):
-
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
600 lbs/acre unfavorable precipitation, 900 lbs/acre normal precipitation, 1,300 lbs/acre 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:
turpentine bush, jojoba, whitethorn, mesquite, prickly pear, cane cholla, ocotillo may increase to undesirable levels in the absence of natural fires; Red brome and wild oats. -
Perennial plant reproductive capability:
Not affected even following several years of prolonged drought period for region.
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