Natural Resources
Conservation Service
Ecological site R051XY286CO
Rocky Foothills
Last updated: 12/11/2024
Accessed: 12/22/2024
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): 051X–High Intermountain Valleys
This MLRA encompasses the San Luis Valley in south central Colorado and the Taos Plateau and Taos alluvial fans of north central New Mexico. As part of the northern portion of the Rio Grande Rift, the MLRA consists of large, alluvium filled basins washed down from adjacent mountain ranges. The Rio Grande River flows through this MLRA, continuing its long function of carrying mountain sediment down to the basin. Cenozoic volcanism is an extensive characteristic of the MLRA where large basalt flows with volcanic hills and domes are abundant.Ancient Lake Alamosa is a large feature within the MLRA.
Classification relationships
NRCS:
Major Land Resource Area 51, High Intermountain Valleys (United States Department of Agriculture, Natural Resources Conservation Service, 2006).
USFS:
331J – Northern Rio Grande Basin M331Ic > 331Ja - San Luis Valley, 331Jb - San Luis Hills and 331C - Mogotes
EPA:
22 - Arizona/New Mexico Plateau > 22a - San Luis Shrublands and Hills ; 22b -San Luis Alluvial Flats and Wetlands ; 22c - Salt Flats; 22e - Sand Dunes and Sand Sheets and 22f -Taos Plateau (Griffith, 2006).
USGS:
Southern Rocky Mountain Province
Ecological site concept
Parent materials are mostly residuum with some colluvium and alluvium, derived from andesite and rhyolite. Soils are shallow. Areas of rock outcrop are scattered throughout. Elevation ranges from 8000 to 9500 feet. Slope position is variable from summit positions to back slopes. The soils are loamy-skeletal with the presence of rocks, cobbles, and stones throughout.
Associated sites
R051XY277CO |
Basalt Hill 7-12 PZ The Basalt Hills site is associated with basalt flows. Rocky Foothills is associated with andesite and rhyolite volcanic landforms. |
---|---|
R051XY276CO |
Limy Bench The Rocky Foothills exists on a volcanic formation while Limy Bench is on the surrounding alluvial fan alluvium. |
R051XY281CO |
Mountain Outwash The Mountain Outwash site is made up of deep alluvium on the slope. The Rocky Foothills is very shallow to moderately deep over a lithic contact. |
R051XY279CO |
Foothill Sand 9-12 PZ The Foothill Sand site occurs alluvial fans at the upper portion of slope, connected to the Sangre de Cristo Mountains. The source of parent material is a mixing of both alluvial material from the mountains and eolian material blown in from the San Luis Valley's sand sheet and active dune field. Surface textures range from very cobbly sandy loam to loamy sand. Taxonomic particle size class ranges from loamy-skeletal to sandy. Soils are deep and slope commonly ranges from 4 to 15 percent. There are stringers of pinyon and juniper extending down from tmountain-base and some scattered P-J throughout the site. |
Similar sites
R051XY281CO |
Mountain Outwash The Mountain Outwash site is made up of deep alluvium on the slope. The Rocky Foothills is very shallow to moderately deep over a lithic contact. |
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Table 1. Dominant plant species
Tree |
(1) Pinus edulis |
---|---|
Shrub |
(1) Ribes cereum |
Herbaceous |
(1) Pascopyrum smithii |
Physiographic features
This site may occur on gentle slopes but is most common on steep, broken land, especially the lower slopes of steep mountain ranges. This site occurs on bedrock controlled slope positions such as the summit, shoulder, and backslope of mountains and mountain slopes.
It is usually dissected by arroyos and small canyons. Slopes range from 2 to 65% and are quite variable. In the driest areas the site may be confined to long northerly-facing slopes. In other places this site is on dry southerly exposures, the opposite slope having a woodland site on them. Elevation is 8,000 to 9,500 feet.
Table 2. Representative physiographic features
Hillslope profile |
(1) Summit (2) Shoulder (3) Backslope |
---|---|
Landforms |
(1)
Mountain
(2) Mountain slope |
Runoff class | Medium to high |
Flooding frequency | None |
Ponding frequency | None |
Elevation | 8,000 – 9,500 ft |
Slope | 2 – 65% |
Aspect | W, NW, N, NE, E, SE, S, SW |
Climatic features
The climate that typifies the High Intermountain Valley, ranges from arid to semi-arid, and is characterized by cold winters, moderate summers, and much sunshine. Average annual precipitation ranges from 7 to 10 inches along the valley floor and throughout most of the resource area. Upper elevations and southern reaches range from 9 to 12 inches. This ecological site occurs in the 12 to 16 inch precipitation zone. Precipitation extremes vary from 3 to 20 inches per year depending on location. The San Juan mountain range to the west and the Sangre de Cristo Mountains to the east intercept much of the precipitation causing a two-way rain shadow effect. Approximately 60 to 65 percent of the annual precipitation falls between May 1 and October 1, mostly from short duration high intensity thundershowers in July and August. Snowfall averages 34 inches annually; snow cover is light or patchy throughout much of the winter. Wind speeds average 7 miles per hour annually. High wind velocities are common in the spring.
Cold air from the encompassing mountain ranges drain into the valley and settle. This phenomena results in long cold winters and moderate summer temperatures. July is the hottest month and January is the coldest. Summer temperatures range from highs in the upper 70’s and low 80’s and occasionally reach to the mid 90o F. Summer nights are cool, with lows averaging in the mid 40’s. Temperatures of -20oF to -40oF can be expected each year and are common during some winters. Higher elevations can receive a dusting of snow as early as September 1. There is a 50% probability that the first frost in the fall will occur near September 16, and the last frost in the spring on about June 9. The average length of the growing season is 119 days and varies from 94 to 143 days. Summer humidity is low. Evaporation rates average lower than those of dry regions because of the cool climate.
Most major plant species initiate growth between mid May and late July, but growth may extend into September. Some cool season plants begin growth earlier and complete growth by mid June.
Note: Great Sand Dunes National Monument (CO) and Cerro (NM) are on the edge of the Valley and only cover the lower range (12-14 inches) of precipitation that this site occurs in. There are no climate stations in that are located in the valley in the upper precipitation range of this ecological site.
Table 3. Representative climatic features
Frost-free period (characteristic range) | 90-91 days |
---|---|
Freeze-free period (characteristic range) | 104-120 days |
Precipitation total (characteristic range) | 12-16 in |
Frost-free period (actual range) | 89-92 days |
Freeze-free period (actual range) | 100-124 days |
Precipitation total (actual range) | 12-16 in |
Frost-free period (average) | 91 days |
Freeze-free period (average) | 112 days |
Precipitation total (average) | 14 in |
Figure 1. Monthly precipitation range
Figure 2. Monthly minimum temperature range
Figure 3. Monthly maximum temperature range
Figure 4. Monthly average minimum and maximum temperature
Figure 5. Annual precipitation pattern
Figure 6. Annual average temperature pattern
Climate stations used
-
(1) CERRO [USC00291630], Questa, NM
-
(2) GREAT SAND DUNES NM [USC00053541], Mosca, CO
Influencing water features
This site does not have a water table.
Soil features
Soils are skeletal with depth and shallow over lithic contact. Occasionally. this site has been correlated to soils that are 20-30 inches in depth. Typically they contain a great deal of smaller rock fragments as well as stones, and occur in a complex pattern with nearly bare rock outcrops and pockets of deeper soils. Deep rooted plants make use of the deeper soil pockets which collect moisture from surrounding rock outcrops, and in cracks in underlying rock. But water storage is limited by rockiness and general lack of depth.
Table 4. Representative soil features
Parent material |
(1)
Residuum
–
andesite
(2) Residuum – volcanic rock (3) Colluvium – tuff (4) Colluvium – andesite |
---|---|
Surface texture |
(1) Very stony, extremely stony, very cobbly loam (2) Gravelly clay loam (3) Very gravelly coarse sandy loam |
Family particle size |
(1) Loamy-skeletal |
Drainage class | Well drained |
Permeability class | Moderately slow to moderately rapid |
Depth to restrictive layer | 10 – 20 in |
Soil depth | 10 – 20 in |
Surface fragment cover <=3" | 5 – 20% |
Surface fragment cover >3" | 5 – 60% |
Available water capacity (Depth not specified) |
0.5 – 2 in |
Calcium carbonate equivalent (Depth not specified) |
Not specified |
Electrical conductivity (Depth not specified) |
Not specified |
Sodium adsorption ratio (Depth not specified) |
Not specified |
Soil reaction (1:1 water) (Depth not specified) |
6.6 – 8.4 |
Subsurface fragment volume <=3" (Depth not specified) |
10 – 45% |
Subsurface fragment volume >3" (Depth not specified) |
10 – 60% |
Ecological dynamics
A rather open or patchy growth of pinon pine and juniper (mostly pinon_ mixed with a patchy stand of grasses and shrubs characterizes this site. Deep rooted plants make use of moisture collecting around boulders, in pockets of deeper soil, and in cracks and fissures in the bedrock. Water storage is limited by the skeletal soils and lack of depth. Tree species are twoneedle pinyon, Utah juniper and in some places Rocky Mountain juniper. Species most likely to increase are snakeweed, rubber rabbitbrush, ring muhly and Colorado rubberweed. As the ecological condition deteriorates the above plants often become prominent, along with hairy goldenaster and large amounts of prickly pear. Grasses may decline to an extremely patchy growth of blue grama. Pinon and juniper may increase substantially.
State and transition model
More interactive model formats are also available.
View Interactive Models
Click on state and transition labels to scroll to the respective text
Ecosystem states
State 1 submodel, plant communities
State 2 submodel, plant communities
State 1
Reference
The reference state has the greatest diversity and production of plants coupled with the least amount of bare ground. This state shows a mosaic of trees, shrubs, grasses, and forbs. Small clusters of pinyon and juniper are scattered throughout where deep and lateral root systems have found areas where moisture collects. Grasses with fibrous root systems such as western wheatgrass, needle and thread, Indian ricegrass, and blue grama take advantage of spring and summer rain to occupy areas where soil has collected between rocks. A diversity of forbs and shrubs use tap root systems to utilize moisture throughout the profile and into the crevices of the bedrock.
Resilience management. The reference state has the greatest resilience to disturbance. The diversity of species and root systems help maintain healthy ecosystem processes.
Community 1.1
Pinyon and Juniper Mosaic
Pinyon and juniper are growing in clusters where roots take advantage of water and nutrients in and around the bedrock. Major grasses include western wheatgrass, needle and thread, Indian ricegrass, and blue grama. Also common are muttongrass, prairie Junegrass, squirreltail, littleseed ricegrass, and (in favored locations) mountain muhly and small amounts of Arizona fescue. Forbs make up a small part of the yield, but some are conspicuous when in bloom. They include buckwheat, paintbrush, penstemon, hairy goldaster, Colorado rubberweed, lupine, and scarlet gilia. Important shrubs are alderleaf mountain mahogany, wax currant, and gooseberry. Serviceberry, skunkbush sumac, snowberry, prairie sagewort, fourwing saltbush, winterfat, prickly pear, and yucca are commonly present, and there may be some rock spirea.
Resilience management. The reference community is the most resilient to disturbance. A diversity of plant species keep the ecological health functional and able to resist colonization by trees.
Dominant plant species
-
twoneedle pinyon (Pinus edulis), tree
-
Utah juniper (Juniperus osteosperma), tree
-
alderleaf mountain mahogany (Cercocarpus montanus), shrub
-
whitestem gooseberry (Ribes inerme var. inerme), shrub
-
western wheatgrass (Pascopyrum smithii), grass
-
needle and thread (Hesperostipa comata), grass
Figure 10. Annual production by plant type (representative values) or group (midpoint values)
Table 5. Annual production by plant type
Plant type | Low (lb/acre) |
Representative value (lb/acre) |
High (lb/acre) |
---|---|---|---|
Grass/Grasslike | 220 | 385 | 495 |
Shrub/Vine | 100 | 175 | 225 |
Tree | 40 | 70 | 90 |
Forb | 40 | 70 | 90 |
Total | 400 | 700 | 900 |
Figure 11. Plant community growth curve (percent production by month). CO5108, Cool-season Dominant Warm-season Subdominant, MLRA 51 Alluvial Fans & fan Remnants. Reference Plant Community for Chico Fan located in LRU 51-5 on fans and fan remnants above valley floor, pre-dominantly in areas surrounding Villa Grove and Saguache, Saguache County..
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 | 0 | 3 | 30 | 25 | 20 | 12 | 10 | 0 | 0 | 0 |
State 2
Pinyon-Juniper
Community 2.1
Pinyon-Juniper
This state has a dominance of pinyon and juniper with some warm season grasses such as blue grama, threeawn and ring muhly. Forbs and shrubs such as snakeweed, rubber rabbitbrush, and Colorado rubberweed may be present as well. Reference species will still be present in protected areas between rocks or within shrubs.
Resilience management. The site has lost valuable ecosystem services such as wildlife habitat and livestock production. Resilience to disturbance is less as species diversity has decreased.
Transition T1A
State 1 to 2
As herbaceous diversity and cover have decreased due to grazing without adequate recovery periods along with over-utilization of preferred species, bare ground becomes available for expansion and germination of pinon and juniper seedlings. As trees slowly expand, deep and lateral root systems dominate available, seasonal moisture intake. The dropping of needle cast also discourages growth by herbaceous plants.
Restoration pathway R2A
State 2 to 1
A set back to the pinyon and juniper mostly by drought, beetle kill, and fire. This disturbance coupled by management that allows for reference species to recover and colonize will allow for long-term restoration of the site.
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 | 275–450 | |||||
western wheatgrass | PASM | Pascopyrum smithii | 80–180 | – | ||
needle and thread | HECO26 | Hesperostipa comata | 50–135 | – | ||
Indian ricegrass | ACHY | Achnatherum hymenoides | 50–135 | – | ||
blue grama | BOGR2 | Bouteloua gracilis | 30–90 | – | ||
muttongrass | POFE | Poa fendleriana | 15–45 | – | ||
squirreltail | ELEL5 | Elymus elymoides | 15–45 | – | ||
littleseed ricegrass | PIMI | Piptatheropsis micrantha | 15–45 | – | ||
mountain muhly | MUMO | Muhlenbergia montana | 0–45 | – | ||
Arizona fescue | FEAR2 | Festuca arizonica | 0–45 | – | ||
prairie Junegrass | KOMA | Koeleria macrantha | 15–45 | – | ||
purple threeawn | ARPU9 | Aristida purpurea | 0–20 | – | ||
mountain brome | BRMA4 | Bromus marginatus | 0–15 | – | ||
roughleaf ricegrass | ORAS | Oryzopsis asperifolia | 0–15 | – | ||
sun sedge | CAINH2 | Carex inops ssp. heliophila | 5–15 | – | ||
pine dropseed | BLTR | Blepharoneuron tricholepis | 0–10 | – | ||
little bluestem | SCSC | Schizachyrium scoparium | 0–10 | – | ||
ring muhly | MUTO2 | Muhlenbergia torreyi | 0–5 | – | ||
Forb
|
||||||
2 | 40–90 | |||||
white sagebrush | ARLU | Artemisia ludoviciana | 0–10 | – | ||
false boneset | BREU | Brickellia eupatorioides | 0–10 | – | ||
Wyoming Indian paintbrush | CALI4 | Castilleja linariifolia | 0–10 | – | ||
lacy tansyaster | MAPI | Machaeranthera pinnatifida | 0–10 | – | ||
bluebells | MERTE | Mertensia | 0–10 | – | ||
Colorado four o'clock | MIMU | Mirabilis multiflora | 0–10 | – | ||
sidebells penstemon | PESE11 | Penstemon secundiflorus | 0–10 | – | ||
scarlet globemallow | SPCO | Sphaeralcea coccinea | 0–10 | – | ||
hairy clematis | CLHI | Clematis hirsutissima | 0–10 | – | ||
James' buckwheat | ERJA | Eriogonum jamesii | 0–10 | – | ||
sulphur-flower buckwheat | ERUM | Eriogonum umbellatum | 0–10 | – | ||
hairy false goldenaster | HEVI4 | Heterotheca villosa | 0–10 | – | ||
fineleaf hymenopappus | HYFI | Hymenopappus filifolius | 0–10 | – | ||
pingue rubberweed | HYRI | Hymenoxys richardsonii | 0–10 | – | ||
scarlet gilia | IPAG | Ipomopsis aggregata | 0–10 | – | ||
narrowleaf stoneseed | LIIN2 | Lithospermum incisum | 0–10 | – | ||
hoary tansyaster | MACA2 | Machaeranthera canescens | 0–10 | – | ||
broom-like ragwort | SESP3 | Senecio spartioides | 0–10 | – | ||
Shrub/Vine
|
||||||
3 | 125–225 | |||||
alderleaf mountain mahogany | CEMO2 | Cercocarpus montanus | 60–135 | – | ||
wax currant | RICE | Ribes cereum | 40–90 | – | ||
whitestem gooseberry | RIINI | Ribes inerme var. inerme | 20–45 | – | ||
skunkbush sumac | RHTR | Rhus trilobata | 10–20 | – | ||
Saskatoon serviceberry | AMAL2 | Amelanchier alnifolia | 0–20 | – | ||
fourwing saltbush | ATCA2 | Atriplex canescens | 0–20 | – | ||
rubber rabbitbrush | ERNA10 | Ericameria nauseosa | 0–20 | – | ||
rockspirea | HODU | Holodiscus dumosus | 0–20 | – | ||
winterfat | KRLA2 | Krascheninnikovia lanata | 0–20 | – | ||
chokecherry | PRVI | Prunus virginiana | 0–20 | – | ||
mountain snowberry | SYOR2 | Symphoricarpos oreophilus | 0–20 | – | ||
spineless horsebrush | TECA2 | Tetradymia canescens | 0–20 | – | ||
soapweed yucca | YUGL | Yucca glauca | 0–10 | – | ||
plains pricklypear | OPPO | Opuntia polyacantha | 0–10 | – | ||
prairie sagewort | ARFR4 | Artemisia frigida | 0–10 | – | ||
broom snakeweed | GUSA2 | Gutierrezia sarothrae | 0–10 | – | ||
Tree
|
||||||
4 | 40–90 | |||||
Utah juniper | JUOS | Juniperus osteosperma | 20–65 | – | ||
twoneedle pinyon | PIED | Pinus edulis | 20–65 | – | ||
Rocky Mountain juniper | JUSC2 | Juniperus scopulorum | 0–20 | – | ||
ponderosa pine | PIPO | Pinus ponderosa | 0–10 | – | ||
Douglas-fir | PSME | Pseudotsuga menziesii | 0–5 | – |
Interpretations
Supporting information
Inventory data references
Location of Typical Example of the Site:
Rocky, north-facing slope along Rock Creek about 11 miles southwest of Monte Vista, Rio Grand County.
Field Offices in Colorado where the site occurs:
Alamosa, Center, and San Luis
Other references
Chapman, S.S., G.E. Griffith, J.M. Omernik, A.B. Price, J. Freeouf, and D.L. Schrupp. 2006. Ecoregions of Colorado. (2-sided color posterwith map, descriptive text, summary tables, and photographs). U.S. Geological Survey, Reston, VA. Scale 1:1,200,000.
Cleland, D.T.; Freeouf, J.A.; Keys, J.E.; Nowacki, G.J.; Carpenter, C.A.; and McNab, W.H. 2007. Ecological Subregions: Sections andSubsections for the conterminous United States. Gen. Tech. Report WO-76D [Map on CD-ROM] (A.M. Sloan, cartographer). Washington,DC: U.S. Department of Agriculture, Forest Service, presentation scale 1:3,500,000; colored.
Soil Conservation Service (SCS). August 1975. Range Site Description for Limy Bench #276. : USDA, Denver Colorado.
United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land Resource Regions and Major Land Resource Areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296.
Contributors
C. Villa, S. Woodall, H. Garcia
Approval
Kirt Walstad, 12/11/2024
Acknowledgments
Project Staff:
Suzanne Mayne-Kinney, Ecological Site Specialist, NRCS MLRA, Grand Junction SSO
Alan Stuebe, MLRA Soil Survey Leader, NRCS MLRA Alamosa SSO
Program Support:
Rachel Murph, NRCS CO State Rangeland Management Specialist, Denver
Eva Muller, Regional Director, Rocky Mountain Regional Soil Survey Office, Bozeman, MT
B.J. Shoup, CO State Soil Scientist, Denver
Eugene Backhaus, CO State Resource Conservationist, Denver
--Site Development and Testing Plan--:
Future work to validate and further refine the information in this Provisional Ecological Site Description is necessary. This will include field activities to collect low-, medium-, and high-intensity sampling, soil correlations, and analysis of that data.
Additional information and data are required to refine the Plant Production and Annual Production tables for this ecological site. The extent of MLRA 51 must be further investigated.
Field testing of the information contained in this Provisional ESD is required. As this ESD is moved to the Approved ESD level, reviews from the technical team, quality control, quality assurance, and peers will be conducted.
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) | C. Villa, S. Woodall, H. Garcia |
---|---|
Contact for lead author | |
Date | 02/06/2005 |
Approved by | Kirt Walstad |
Approval date | |
Composition (Indicators 10 and 12) based on | Annual Production |
Indicators
-
Number and extent of rills:
None -
Presence of water flow patterns:
Flow paths are short and disconnected. Broken by surface rock and basal cover. -
Number and height of erosional pedestals or terracettes:
Pedestals are minimal and associated with flow paths. Debris dams are obvious following rainfall event. Roots not exposed. -
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
Expect 5% or less bare ground. Surface and sub-surface rock are inherent to this site. -
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):
Some movement is expected due to steepness of slope. Distance varies from 1-3 feet following intense rainfall events. -
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Stability class rating anticipated to be 3-4 in the interspaces at soil surface. -
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
SOM ranges from 0.5-3%. Soils are shallow, surface texts are very stony, extremely stony, very cobbly loam. gravelly clay loam or very gravelly coarse sandy loam, and are well drained. The A-horizon ranges from 3-14 inches in depth and color ranges from grayish brown to dark grayish brown. Surface structure is weak fine granular, moderate very fine granular structure, or moderate medium granular structure. -
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
The distribution of diverse grass, shrub, tree/forb canopy and root structure reduces raindrop impact and slows overland flow providing increased time for infiltration to occur. Also, the abundance of rock on the surface, slows velocity of runoff and acts to increase infiltration. -
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:
cool season bunchgrass >Sub-dominant:
shrubs > cool season rhizomatous grass > trees > warm season bunchgrass >Other:
forbsAdditional:
-
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
Perennial vegetation should show minimal mortality/decadence except during extreme drought when some decadence or mortality is expected. -
Average percent litter cover (%) and depth ( in):
10-15% litter cover at 0.25 inch depth or less. Extended drought can reduce litter to 5-10%. -
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
500 lbs./ac. low precip years; 800 lbs./ac. average precip years; 1000 lbs./ac. above average precip years. After extended drought or the first growing season following wildfire, production may be significantly reduced by 100 – 200 lbs./ac. or more. -
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:
None -
Perennial plant reproductive capability:
The only limitations are weather-related, wildfire, natural disease, inter-species competition, wildlife, and insects that may temporarily reduce reproductive capability.
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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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