Natural Resources
Conservation Service
Ecological site R040XA124AZ
Loamy Bottom, Woodland 10"-13" p.z.
Last updated: 10/17/2024
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.
MLRA notes
Major Land Resource Area (MLRA): 040X–Sonoran Basin and Range
Major Land Resource Area (MLRA) 40 is the portion of Sonoran Desert that extends from northwest Mexico into southwestern Arizona and southeastern California. This MLRA is hot desert characterized by bimodal precipitation coupled with hot summers and mild winters. These conditions give rise to a rich biological diversity visually dominated by columnar cactus (saguaro) and leguminous trees (palo verde). 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 basin sediments are combinations of fluvial, lacustrine, colluvial and alluvial deposits.
LRU notes
Land Resource Unit (LRU) 40-1, Upper Sonoran Desert, is characterized by desert scrub vegetation with no desert pavement present. Trees grow on uplands as well as in washes and on hillslopes. Elevations range from 2000 to 3800 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.
Classification relationships
USDA-NRCS Land Resource Regions and Major Land Resource Areas of the United States, the Caribbean, and the Pacific Basin: Western Range and Irrigated Region D Major Land Resource Area 40 - Sonoran Basin and Range Land Resource Unit 1 - Upper Sonoran Desert Ecological Site Loamy Bottom, Woodland, 10"-13" p.z.
U.S. Environmental Protection Agency, Ecological Regions of North America: Level I, Region 10 North American Deserts Level II, 10.2 Warm Deserts Level III, Ecoregion 81, Sonoran Basin and Range Level IV, 81l, 81n, 81o
USDA-USFS Ecological Subregions: Sections of the Conterminous United States Section 322 American Semidesert and Desert Province Section 322B, Sonoran Desert
Ecological site concept
Loamy Bottom, Woodland, 10"-13" p.z., occurs in a bottom position, receiving both rainfall and run-on moisture. The water table is available to the plant community. Soils do not have redoximorphic features within 80" of surface.
Associated sites
R040XA125AZ |
Sandy Bottom, Woodland 10"-13" p.z. adjacent water flow channel, soils with redox features |
---|---|
R040XA112AZ |
Loamy Swale 10"-13" p.z. non-saline bottom site without permanent, deep, water table; often associated adjacent opposite water channel |
Similar sites
F040XB214AZ |
Loamy Bottom, Woodland 7"-10" p.z. Elevations 1,200' - 2,000', lower precipitation, soil hyperthermic |
---|---|
F040XC328AZ |
Loamy Bottom, Woodland 3"-7" p.z. Elevations 300' - 1,200', lower precipitation, soil hyperthermic |
Table 1. Dominant plant species
Tree |
(1) Prosopis velutina |
---|---|
Shrub |
Not specified |
Herbaceous |
(1) Sporobolus wrightii |
Physiographic features
This site occurs on stream terraces of major drainageways. It does not experience regular overbank flooding. Some extra moisture may be received from valley side channel flooding. Water table depths are estimated to range from 10 to 50 feet. Stream channels are deeply entrenched.
Table 2. Representative physiographic features
Landforms |
(1)
Stream terrace
|
---|---|
Flooding duration | Extremely brief (0.1 to 4 hours) to brief (2 to 7 days) |
Flooding frequency | None to rare |
Ponding duration | Very brief (4 to 48 hours) to brief (2 to 7 days) |
Ponding frequency | None to rare |
Elevation | 2,000 – 3,800 ft |
Slope | 2% |
Aspect | Aspect is not a significant factor |
Climatic features
Annual precipitation ranges from 10 to 13 inches in the southern part of this LRU, with elevations between 1900 and 3200 feet. Annual precipitation in the northern part ranges from 11 to 14 inches, with elevations between 2000 and 3800 feet. Rainfall ratios range from 40:60 (winter:summer) in the southern part, 50:50 in the central portion, and 60:40 in the northern part.
Overall, average annual rainfall is variable, but increases in variability from east to west across the region. For long-term precipitation data, the coefficient of variation, the ratio of the standard deviation to the mean expressed as a percentage, increases from 29% at Tucson (east) to 36% at Carefree (west).
Rainfall intensity differs between rainfall seasons. Winter frontal storms develop in the Pacific Ocean and Gulf of California, producing widespread, low-intensity and long duration precipitation events. Snowfall is rare and seldom last for more than a few hours. During summer months (July-September), atmospheric activity in the Gulf of Mexico produces convective thunderstorms of short duration, usually less than 30 minutes, but of moderate to heavy intensity. May and June are the driest months of the year. Humidity is generally very low.
Winter temperatures are mild, with only a few days of freezing temperatures overnight. Summer temperatures are warm to hot, with several days in June and July exceeding 105°F.
Spring and the summer growing seasons are equally important for perennial grass, forb and shrub growth. With above average precipitation, cool and warm season annual forbs and grasses can be common in their respective seasons. Perennial forage species can remain green throughout the year with sufficient available moisture.
Table 3. Representative climatic features
Frost-free period (average) | 265 days |
---|---|
Freeze-free period (average) | |
Precipitation total (average) | 13 in |
Figure 1. Monthly precipitation range
Figure 2. Monthly average minimum and maximum temperature
Influencing water features
There are no water features associated with this site.
Soil features
These are young soils formed in loamy or silty alluvium of mixed origin. Soils are deep, well drained and may be calcareous or slightly saline, and may contain 0%-5% gypsum. Plant-soil moisture relationships are excellent for deep rooted trees due to a deep ground water table.
Table 4. Representative soil features
Surface texture |
(1) Fine sandy loam (2) Loam (3) Silt loam |
---|---|
Family particle size |
(1) Loamy |
Drainage class | Well drained |
Permeability class | Moderate to moderately slow |
Soil depth | 60 in |
Surface fragment cover <=3" | 10% |
Surface fragment cover >3" | 1% |
Available water capacity (0-40in) |
5.8 – 10.8 in |
Calcium carbonate equivalent (0-40in) |
10% |
Electrical conductivity (0-40in) |
4 mmhos/cm |
Sodium adsorption ratio (0-40in) |
13 |
Soil reaction (1:1 water) (0-40in) |
7 – 8.2 |
Subsurface fragment volume <=3" (Depth not specified) |
5% |
Ecological dynamics
Loamy Bottom, Woodland, 10-13” p.z. supports a mixed plant community, with an overstory of mesquite and an understory of shrubs, perennial grasses and forbs. Leaf-out for mesquite occurs midspring, after the last frost, produces flowers in late spring or early summer, and mature fruits begin dropping by July. The trees lose their leaves with the first hard frost. The aspect is deciduous woodland.
The site is very susceptible to channel and streambank erosion. Drainageways are deeply entrenched and, if streamside vegetation is disturbed, bank cutting can greatly increase. If the mesquite overstory is reduced, shrub cover will readily expand and become dominant in the plant community. Herbaceous understory density varies with varying canopy cover. Mesquite canopy cover ranges from 30%–65%. Trees can reach maximum size and height on the site. Excessive groundwater pumping can, over time, lower water tables beyond the reach of tree roots and cause extensive tree loss. Tree species vigorously sprout after a fire or manual cutting. Natural fires may have been important in maintaining herbaceous understories. Saltcedar can invade and dominate following disturbance of the native tree cover. Bermudagrass, Johnson grass, foxtail barley and London rocket are introduced species commonly found on this site.
State and transition model
Figure 3. Loamy Bottom, Woodland STM
Figure 4. Loamy Bottom, woodland, 10-13" p.z. STM Legend
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 1
Mesquite Bosque, Native State
Community 1.1
Mesquite, Native Community (Reference)
Mesquite dominates the reference plant community with a mixed understory.
Figure 5. Annual production by plant type (representative values) or group (midpoint values)
Table 5. Annual production by plant type
Plant type | Low (lb/acre) |
Representative value (lb/acre) |
High (lb/acre) |
---|---|---|---|
Tree | 300 | 475 | 650 |
Shrub/Vine | 350 | 400 | 450 |
Grass/Grasslike | 250 | 275 | 300 |
Forb | 200 | 225 | 250 |
Total | 1100 | 1375 | 1650 |
State 2
Mesquite Bosque, Exotics State
Mesquite canopy intact, and groundwater table within normal range. Non-native annual forbs and grasses, such as London rocket and foxtail barley, dominate the understory. Shrubs and succulents are sparsely present. No flooding occurs.
State 3
Abandoned Farmland State
Mesquite bosque absent, and groundwater table within normal range. Initially, native annual forbs and grasses occupy the site, with some patches of non-native annuals. With time, desert broom, greythorn and other shrubs come to dominate the community, with patches of perennial grasses occurring in depressions.
State 4
Mesquite Scrubland State
Water table depleted. Mesquite bosque has altered to a shrubby aspect with a 5%-20% canopy, intermingled with greythorn and other large shrubs.
State 5
Non-Native Woodland State
Saltcedar dominates, becoming an impenetrable thicket.
Additional community tables
Table 6. Community 1.1 plant community composition
Group | Common name | Symbol | Scientific name | Annual production (lb/acre) | Foliar cover (%) | |
---|---|---|---|---|---|---|
Grass/Grasslike
|
||||||
1 | 28–41 | |||||
Arizona cottontop | DICA8 | Digitaria californica | 28–41 | – | ||
bush muhly | MUPO2 | Muhlenbergia porteri | 28–41 | – | ||
whiplash pappusgrass | PAVA2 | Pappophorum vaginatum | 28–41 | – | ||
plains bristlegrass | SEVU2 | Setaria vulpiseta | 28–41 | – | ||
spike dropseed | SPCO4 | Sporobolus contractus | 28–41 | – | ||
big sacaton | SPWR2 | Sporobolus wrightii | 28–41 | – | ||
2 | 14–28 | |||||
Santa Rita threeawn | ARCAG | Aristida californica var. glabrata | 14–28 | – | ||
Havard's threeawn | ARHA3 | Aristida havardii | 14–28 | – | ||
purple threeawn | ARPU9 | Aristida purpurea | 14–28 | – | ||
Parish's threeawn | ARPUP5 | Aristida purpurea var. parishii | 14–28 | – | ||
spidergrass | ARTE3 | Aristida ternipes | 14–28 | – | ||
low woollygrass | DAPU7 | Dasyochloa pulchella | 14–28 | – | ||
saltgrass | DISP | Distichlis spicata | 14–28 | – | ||
squirreltail | ELELE | Elymus elymoides ssp. elymoides | 14–28 | – | ||
vine mesquite | PAOB | Panicum obtusum | 14–28 | – | ||
tobosagrass | PLMU3 | Pleuraphis mutica | 14–28 | – | ||
cane bluestem | BOBA3 | Bothriochloa barbinodis | 14–28 | – | ||
sand dropseed | SPCR | Sporobolus cryptandrus | 14–28 | – | ||
sideoats grama | BOCU | Bouteloua curtipendula | 14–28 | – | ||
slim tridens | TRMU | Tridens muticus | 14–28 | – | ||
3 | 28–41 | |||||
prairie threeawn | AROL | Aristida oligantha | 28–41 | – | ||
needle grama | BOAR | Bouteloua aristidoides | 28–41 | – | ||
sixweeks grama | BOBA2 | Bouteloua barbata | 28–41 | – | ||
Rothrock's grama | BORO2 | Bouteloua rothrockii | 28–41 | – | ||
Arizona brome | BRAR4 | Bromus arizonicus | 28–41 | – | ||
brome | BROMU | Bromus | 28–41 | – | ||
feather fingergrass | CHVI4 | Chloris virgata | 28–41 | – | ||
bearded cupgrass | ERAR5 | Eriochloa aristata | 28–41 | – | ||
canyon cupgrass | ERLE7 | Eriochloa lemmonii | 28–41 | – | ||
desert lovegrass | ERPEM | Eragrostis pectinacea var. miserrima | 28–41 | – | ||
tufted lovegrass | ERPEP2 | Eragrostis pectinacea var. pectinacea | 28–41 | – | ||
little barley | HOPU | Hordeum pusillum | 28–41 | – | ||
Mexican sprangletop | LEFUU | Leptochloa fusca ssp. uninervia | 28–41 | – | ||
mucronate sprangeltop | LEPAB | Leptochloa panicea ssp. brachiata | 28–41 | – | ||
delicate muhly | MUFR | Muhlenbergia fragilis | 28–41 | – | ||
littleseed muhly | MUMI | Muhlenbergia microsperma | 28–41 | – | ||
witchgrass | PACA6 | Panicum capillare | 28–41 | – | ||
Bigelow's bluegrass | POBI | Poa bigelovii | 28–41 | – | ||
Arizona signalgrass | URAR | Urochloa arizonica | 28–41 | – | ||
sixweeks fescue | VUOC | Vulpia octoflora | 28–41 | – | ||
Forb
|
||||||
4 | 2–11 | |||||
bigseed alfalfa dodder | CUIN | Cuscuta indecora | 2–11 | – | ||
mesquite mistletoe | PHCA8 | Phoradendron californicum | 2–11 | – | ||
5 | 23–34 | |||||
dwarf desertpeony | ACNA2 | Acourtia nana | 23–34 | – | ||
wheelscale saltbush | ATEL | Atriplex elegans | 23–34 | – | ||
Wright's saltbush | ATWR | Atriplex wrightii | 23–34 | – | ||
hedge bamboo | BAMU2 | Bambusa multiplex | 23–34 | – | ||
New Mexico thistle | CINE | Cirsium neomexicanum | 23–34 | – | ||
fingerleaf gourd | CUDI | Cucurbita digitata | 23–34 | – | ||
Missouri gourd | CUFO | Cucurbita foetidissima | 23–34 | – | ||
coyote gourd | CUPA | Cucurbita palmata | 23–34 | – | ||
desert thorn-apple | DADI2 | Datura discolor | 23–34 | – | ||
pricklyburr | DAIN2 | Datura inoxia | 23–34 | – | ||
Indian rushpea | HOGL2 | Hoffmannseggia glauca | 23–34 | – | ||
redstar | IPCO3 | Ipomoea coccinea | 23–34 | – | ||
Gila manroot | MAGI | Marah gilensis | 23–34 | – | ||
lacy tansyaster | MAPIP4 | Machaeranthera pinnatifida ssp. pinnatifida var. pinnatifida | 23–34 | – | ||
desert tobacco | NIOBO | Nicotiana obtusifolia var. obtusifolia | 23–34 | – | ||
Mexican passionflower | PAME2 | Passiflora mexicana | 23–34 | – | ||
doubleclaw | PRPA2 | Proboscidea parviflora | 23–34 | – | ||
canaigre dock | RUHY | Rumex hymenosepalus | 23–34 | – | ||
silverleaf nightshade | SOEL | Solanum elaeagnifolium | 23–34 | – | ||
6 | 23–34 | |||||
brownfoot | ACWR5 | Acourtia wrightii | 23–34 | – | ||
trailing windmills | ALIN | Allionia incarnata | 23–34 | – | ||
weakleaf bur ragweed | AMCO3 | Ambrosia confertiflora | 23–34 | – | ||
carelessweed | AMPA | Amaranthus palmeri | 23–34 | – | ||
bristly fiddleneck | AMTE3 | Amsinckia tessellata | 23–34 | – | ||
rockcress | ARABI | Arabidopsis | 23–34 | – | ||
milkvetch | ASTRA | Astragalus | 23–34 | – | ||
scarlet spiderling | BOCO | Boerhavia coccinea | 23–34 | – | ||
Coulter's spiderling | BOCO2 | Boerhavia coulteri | 23–34 | – | ||
hoary bowlesia | BOIN3 | Bowlesia incana | 23–34 | – | ||
Arizona wrightwort | CAAR7 | Carlowrightia arizonica | 23–34 | – | ||
whitemargin sandmat | CHAL11 | Chamaesyce albomarginata | 23–34 | – | ||
goosefoot | CHENO | Chenopodium | 23–34 | – | ||
hyssopleaf sandmat | CHHY3 | Chamaesyce hyssopifolia | 23–34 | – | ||
cryptantha | CRYPT | Cryptantha | 23–34 | – | ||
hairy prairie clover | DAMO | Dalea mollis | 23–34 | – | ||
American wild carrot | DAPU3 | Daucus pusillus | 23–34 | – | ||
western tansymustard | DEPI | Descurainia pinnata | 23–34 | – | ||
Palmer's spectaclepod | DICA31 | Dimorphocarpa candicans | 23–34 | – | ||
flatcrown buckwheat | ERDE6 | Eriogonum deflexum | 23–34 | – | ||
miniature woollystar | ERDI2 | Eriastrum diffusum | 23–34 | – | ||
buckwheat | ERIOG | Eriogonum | 23–34 | – | ||
California poppy | ESCAM | Eschscholzia californica ssp. mexicana | 23–34 | – | ||
Mexican fireplant | EUHE4 | Euphorbia heterophylla | 23–34 | – | ||
hairy desertsunflower | GECA2 | Geraea canescens | 23–34 | – | ||
redstar | IPCO3 | Ipomoea coccinea | 23–34 | – | ||
Arizona poppy | KAGR | Kallstroemia grandiflora | 23–34 | – | ||
Gordon's bladderpod | LEGO | Lesquerella gordonii | 23–34 | – | ||
shaggyfruit pepperweed | LELA | Lepidium lasiocarpum | 23–34 | – | ||
Coulter's lupine | LUSP2 | Lupinus sparsiflorus | 23–34 | – | ||
lacy tansyaster | MAPIP4 | Machaeranthera pinnatifida ssp. pinnatifida var. pinnatifida | 23–34 | – | ||
Nuttall's povertyweed | MONU | Monolepis nuttalliana | 23–34 | – | ||
glandular threadplant | NEGL | Nemacladus glanduliferus | 23–34 | – | ||
Florida pellitory | PAFL3 | Parietaria floridana | 23–34 | – | ||
manybristle chinchweed | PEPA2 | Pectis papposa | 23–34 | – | ||
phacelia | PHACE | Phacelia | 23–34 | – | ||
desert Indianwheat | PLOV | Plantago ovata | 23–34 | – | ||
purslane | PORTU | Portulaca | 23–34 | – | ||
sage | SALVI | Salvia | 23–34 | – | ||
sleepy silene | SIAN2 | Silene antirrhina | 23–34 | – | ||
desert globemallow | SPAM2 | Sphaeralcea ambigua | 23–34 | – | ||
scarlet globemallow | SPCO | Sphaeralcea coccinea | 23–34 | – | ||
woollyhead neststraw | STMI2 | Stylocline micropoides | 23–34 | – | ||
brownplume wirelettuce | STPA4 | Stephanomeria pauciflora | 23–34 | – | ||
sand fringepod | THCU | Thysanocarpus curvipes | 23–34 | – | ||
woolly tidestromia | TILA2 | Tidestromia lanuginosa | 23–34 | – | ||
Shrub/Vine
|
||||||
7 | 100–140 | |||||
fourwing saltbush | ATCA2 | Atriplex canescens | 100–140 | – | ||
Palmer's cock's comb | CEPA5 | Celosia palmeri | 100–140 | – | ||
Drummond's clematis | CLDR | Clematis drummondii | 100–140 | – | ||
western white clematis | CLLI2 | Clematis ligusticifolia | 100–140 | – | ||
longleaf jointfir | EPTR | Ephedra trifurca | 100–140 | – | ||
water jacket | LYAN | Lycium andersonii | 100–140 | – | ||
desert-thorn | LYCIU | Lycium | 100–140 | – | ||
Arizona desert-thorn | LYEX | Lycium exsertum | 100–140 | – | ||
lotebush | ZIOB | Ziziphus obtusifolia | 100–140 | – | ||
8 | 2–40 | |||||
whitethorn acacia | VACO9 | Vachellia constricta | 20–40 | – | ||
iodinebush | ALOC2 | Allenrolfea occidentalis | 20–40 | – | ||
cattle saltbush | ATPO | Atriplex polycarpa | 20–40 | – | ||
desertbroom | BASA2 | Baccharis sarothroides | 20–40 | – | ||
singlewhorl burrobrush | HYMO | Hymenoclea monogyra | 20–40 | – | ||
alkali goldenbush | ISACA2 | Isocoma acradenia var. acradenia | 20–40 | – | ||
southern goldenbush | ISPL | Isocoma pluriflora | 20–40 | – | ||
burroweed | ISTE2 | Isocoma tenuisecta | 20–40 | – | ||
creosote bush | LATRT | Larrea tridentata var. tridentata | 20–40 | – | ||
nightblooming cereus | PEGRT | Peniocereus greggii var. transmontanus | 20–40 | – | ||
soaptree yucca | YUEL | Yucca elata | 20–40 | – | ||
Tree
|
||||||
9 | 5–24 | |||||
catclaw acacia | SEGR4 | Senegalia greggii | 5–24 | – | ||
Jerusalem thorn | PAAC3 | Parkinsonia aculeata | 5–24 | – | ||
honey mesquite | PRGLG | Prosopis glandulosa var. glandulosa | 5–24 | – | ||
10 | 143–285 | |||||
velvet mesquite | PRVE | Prosopis velutina | 143–285 | – | ||
11 | 5–24 | |||||
netleaf hackberry | CELAR | Celtis laevigata var. reticulata | 5–24 | – | ||
desert willow | CHLI2 | Chilopsis linearis | 5–24 | – | ||
Jerusalem thorn | PAAC3 | Parkinsonia aculeata | 5–24 | – | ||
screwbean mesquite | PRPU | Prosopis pubescens | 5–24 | – | ||
American black elderberry | SANIC4 | Sambucus nigra ssp. canadensis | 5–24 | – |
Interpretations
Animal community
This site produces good quantities of spring annual forbs and grasses prior to canopy leaf-out in April. If summer bean crops are harvested, care should be taken to avoid overgrazing the warm season perennial grasses. Horses should not be grazed when a bean crop exists in the trees or on the ground in the summer rainy season.
This site is extremely important to a variety of wildlife, offering well-wooded habitat adjacent to free water in the streambeds for part or all of the year.
Wood products
Fuelwood harvest should not reduce canopy cover to less than 20% to limit an increase in undesirable shrub cover. Coppice sprouts achieve canopy dominance faster if stumps are greater than 30 inches in height. Coppice production cuts should occur every 20 to 30 years. Trees should not be cut near streambanks. There are no soil-site factors limiting wood production.
Supporting information
Type locality
Location 1: Pima County, AZ | |
---|---|
Township/Range/Section | T8S R17E S7 |
General legal description | Tucson FO - San Pedro River - 7B Ranch at Mammoth, SW 1/4 Sec. 7 |
Location 2: Cochise County, AZ | |
Township/Range/Section | T11S R18E S23 |
General legal description | Willcox FO - San Pedro River |
Location 3: Pinal County, AZ | |
Township/Range/Section | T4S R12E S6 |
General legal description | Casa Grande FO - Gila River - 15 Ranch |
Location 4: Pima County, AZ | |
Township/Range/Section | T15S R13E S35 |
General legal description | Sells FO - San Xavier |
Contributors
Dan Robinett
Larry D. Ellicott
Wilma J Renken
Approval
Kendra Moseley, 10/17/2024
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) | |
---|---|
Contact for lead author | |
Date | 10/20/2024 |
Approved by | Kendra Moseley |
Approval date | |
Composition (Indicators 10 and 12) based on | Annual Production |
Indicators
-
Number and extent of rills:
-
Presence of water flow patterns:
-
Number and height of erosional pedestals or terracettes:
-
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
-
Number of gullies and erosion associated with gullies:
-
Extent of wind scoured, blowouts and/or depositional areas:
-
Amount of litter movement (describe size and distance expected to travel):
-
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
-
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
-
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
-
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction 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:
Sub-dominant:
Other:
Additional:
-
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
-
Average percent litter cover (%) and depth ( in):
-
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
-
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:
-
Perennial plant reproductive capability:
Print Options
Sections
Font
Other
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.
Click on box and path labels to scroll to the respective text.