Natural Resources
Conservation Service
Ecological site R070BY051NM
Sandstone Savanna
Last updated: 9/12/2023
Accessed: 12/21/2024
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.
Ecological site concept
This site occurs on gently sloping to moderately steep canyon walls, hillsides, and mesa tops. Slopes are usually 5 to 15 percent but may range from 0 (flat rock areas) to 25 percent (inclusions of short steeper slopes).
Soils are very shallow to shallow. Surface textures are fine sandy loam, sandy loam, or loamy fine sand. Some may have textures of stony sandy loam or cobbly fine sandy loam.
Sandstone bedrock is at depths of 7 to 20 inches.
The Sandstone Savannah ecological site is associated with Shallow Sandstone, Sandy Loam, and Loamy ecological sites.
Table 1. Dominant plant species
| Tree |
(1) Juniperus |
|---|---|
| Shrub |
(1) Krascheninnikovia lanata |
| Herbaceous |
(1) Bouteloua gracilis |
Physiographic features
This site is on gently sloping to moderately steep canyon walls, hillsides, and mesa tops. Slopes are usually 5 to 15 percent but may range from 0 (flat rock areas) to 25 percent ( inclusions of short steeper slopes). Elevation ranges from 3,800 to 5,500 feet. The landscape is typically a complex of small pockets of soil interspersed with sandstone outcrop in the form of ledges.
Table 2. Representative physiographic features
| Landforms |
(1)
Hill
(2) Mesa (3) Cuesta |
|---|---|
| Elevation | 3,800 – 5,500 ft |
| Slope | 25% |
| Aspect | Aspect is not a significant factor |
Climatic features
The climate of this area can be classified as “semi-arid continental”.
Annual average precipitation ranges from 11 to 16 inches. Roughly 78 percent of the moisture falls during the 6-month period of May through October. Most of this summer precipitation falls in the form of brief and heavy afternoon and evening thunderstorms. Hail may accompany the more severe summer storms. In the winter, there is normally only one day a month when as much as one-tenth inch of moisture falls, usually in the form of snow. Snow seldom lies on the ground for more than a few days.
Temperatures are characterized by a distinct seasonal change and large annual and diurnal temperature ranges. Summers are moderately warm. Maximum temperature average above 90 degrees F from July to August, and an average summer includes about 80 days with high readings exceeding 90 degrees F and 10 days with readings above 100 degrees F. Temperatures usually fall rapidly after sundown and lows average 60 degrees F on most summer nights. Winters are mild, sunny, and dry. Daytime shade temperatures in midwinter usually rise to the 50’s. However, freezing temperatures normally occur at night from mid-November to mid-March.
The freeze-free season ranges from 196 to 218 days. Dates of the last freeze range from April 11th to April 17th and the first freeze ranges from October 20th to October 25th.
Both temperature and rainfall distribution favor warm-season, perennial plant communities in the area. However, sufficient late winter and early spring moisture allows cool-season species to occupy a minor component within the plant community.
Climate data was obtained from http://www.wrcc.dri.edu/summary/climsmnm.html web site. Data were interpreted utilizing NM Climate Summarizer spreadsheet.
Table 3. Representative climatic features
| Frost-free period (average) | 192 days |
|---|---|
| Freeze-free period (average) | 218 days |
| Precipitation total (average) | 16 in |
Figure 2. Monthly precipitation range
Figure 3. Monthly average minimum and maximum temperature
Influencing water features
This site is not influenced by water from a wetland or stream.
Soil features
Soils are very shallow to shallow. Surface textures are fine sandy loam, sandy loam, and loamy fine sand. Some may have textures of stony sandy loam or cobbly fine sandy loam. Subsurface textures are most often fine sandy loam, sandy loam, stony sandy loam, or cobbly fine sandy loam. Less often, subsoils have textures of sandy clay loam, and contain clay films.
Sandstone bedrock is at depths of 7 to 20 inches. The air-water relationship is favorable for plant growth. Rock fragments make up 5 to 30 percent of the soil profile.
Characteristic soils:
Lacoca
Latom
Newkirk
Table 4. Representative soil features
| Surface texture |
(1) Loamy fine sand (2) Cobbly fine sandy loam (3) Fine sandy loam |
|---|---|
| Drainage class | Well drained to moderately well drained |
| Permeability class | Moderately slow |
| Soil depth | 7 – 20 in |
| Surface fragment cover <=3" | 5 – 15% |
| Surface fragment cover >3" | 5 – 10% |
| Available water capacity (0-40in) |
1 – 3 in |
| Calcium carbonate equivalent (0-40in) |
1 – 7% |
| Electrical conductivity (0-40in) |
2 mmhos/cm |
| Sodium adsorption ratio (0-40in) |
Not specified |
| Soil reaction (1:1 water) (0-40in) |
6.4 – 8.4 |
| Subsurface fragment volume <=3" (Depth not specified) |
5 – 15% |
| Subsurface fragment volume >3" (Depth not specified) |
5 – 10% |
Ecological dynamics
This ecological site occurs on hills, mesas, and dipslopes of cuestas. It is dominated by warm-season short and mid-grasses, with scattered trees, shrubs and forbs. Grasses make up approximately 70 percent of the annual vegetative production. Shrubs and forbs are evenly distributed and can make up an important portion of the plant community. Juniper and pinyon are often associated with very shallow soils along ledges and rock outcrop. Blue grama and sideoats grama are the dominant grasses of the reference plant community. Seed dispersal by livestock and wildlife, decreased fire frequency, loss of grass cover, and periods of mild wet winters may facilitate an increase in woody species.
State and transition model
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Ecosystem states
State 1 submodel, plant communities
State 2 submodel, plant communities
State 1
Reference State
This state represents the most ecologically stable conditions in terms of resistance to erosion. Moreover, this state has the highest potential for productivity and plant diversity.
Community 1.1
Reference Plant Community
Mixed-Shrub Grassland: In the reference plant community, blue grama and sideoats grama are the dominant grasses. Other species that typically occur in significant amounts include black grama, little bluestem, and New Mexico feathergrass. Common forbs include, bladderpod, Indian paintbrush, and globemallow. Juniper, winterfat, yucca, pinyon, sacahuista, and skunkbush sumac are a few of the woody species common to this site. Continuous heavy grazing pressure can cause a decrease in sideoats grama, black grama, little bluestem, New Mexico feathergrass, and winterfat. Communities dominated by blue and hairy grama may result. Other subordinate species that typically increase in representation includes, ring muhly, threeawns, wolfstail, and broom snakeweed. Diagnosis: Species of grama grasses dominate the site. Grass cover is uniform with few large bare areas. Shrubs are present and evenly distributed. Combined canopy cover of shrubs and trees averages 10 percent. There is little evidence of erosion.
Figure 4. 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 | 280 | 560 | 840 |
| Forb | 60 | 120 | 180 |
| Tree | 40 | 80 | 120 |
| Shrub/Vine | 20 | 40 | 60 |
| Total | 400 | 800 | 1200 |
Table 6. Soil surface cover
| Tree basal cover | 0% |
|---|---|
| Shrub/vine/liana basal cover | 5-15% |
| Grass/grasslike basal cover | 15-25% |
| Forb basal cover | 1-5% |
| Non-vascular plants | 0% |
| Biological crusts | 0% |
| Litter | 15-25% |
| Surface fragments >0.25" and <=3" | 1-5% |
| Surface fragments >3" | 15-25% |
| Bedrock | 0% |
| Water | 0% |
| Bare ground | 20-30% |
Figure 5. Plant community growth curve (percent production by month). NM4001, R070BY051NM Sandstone Savanna HCPC. R070BY051NM Sandstone Savanna HCPC Mid and short grassland with minor components of forbs and shrubs..
| 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 | 3 | 5 | 10 | 10 | 25 | 30 | 12 | 5 | 0 | 0 |
State 2
Woody Encroached
This state has been encroached by woody species--most often oneseed juniper.
Community 2.1
Woody Encroached
Additional States: Woody-Encroached: This site is characterized by the noticeable increase of woody species including juniper, cholla, or sacahuista. These species may occur in combination or individually. Under proper grazing management grass communities tend to be similar to those that occur in the Mixed-Shrub Grassland state. Under continued heavy grazing pressure, species such as ring muhly, threeawns, wolfstail, and broom snakeweed may continue to increase in representation. Diagnosis: Woody species, including juniper, cholla, or sacahuista are found at increased densities. Grass cover is variable ranging from fairly uniform to patchy with frequent large bare areas present. Rills and small gullies may be present especially on the steeper slopes. Wind scoured or depositional areas may be present as cover declines. Transition to Woody-Encroached (1a) ) Seed dispersal by livestock and wildlife and decreased fire frequency may facilitate the encroachment of juniper, cholla, and sacahuista. Variation in precipitation patterns such as a period of mild winters and above average precipitation may produce conditions favorable to the expansion of woody species initiating periods of increased recruitment and establishment. Additionally, decreased grass cover may aid the establishment of woody species by providing competition-free areas for seedling establishment. Key indicators of approach to transition: Decrease or change in distribution of grass cover. Increase in amount of woody seedlings. Transition back to Mixed-Shrub Grassland (1b) Brush control is necessary to reduce the canopy cover of woody species and maintain grass dominance. Periodic use of prescribed fire may be useful in reducing and maintaining shrub densities.2,4 Prescribed grazing will help ensure proper forage use following brush control.
Transition T1A
State 1 to 2
Seed dispersal by livestock and wildlife and decreased fire frequency may facilitate the encroachment of juniper, cholla, and sacahuista. Variation in precipitation patterns such as a period of mild winters and above average precipitation may produce conditions favorable to the expansion of woody species initiating periods of increased recruitment and establishment. Additionally, decreased grass cover may aid the establishment of woody species by providing competition-free areas for seedling establishment. Key indicators of approach to transition: Decrease or change in distribution of grass cover. Increase in amount of woody seedlings.
Restoration pathway R2A
State 2 to 1
Brush control is necessary to reduce the canopy cover of woody species and maintain grass dominance. Periodic use of prescribed fire may be useful in reducing and maintaining shrub densities. Prescribed grazing will help ensure proper forage use following brush control.
Additional community tables
Table 7. Community 1.1 plant community composition
| Group | Common name | Symbol | Scientific name | Annual production (lb/acre) | Foliar cover (%) | |
|---|---|---|---|---|---|---|
|
Grass/Grasslike
|
||||||
| 1 | 120–136 | |||||
| blue grama | BOGR2 | Bouteloua gracilis | 120–136 | – | ||
| 2 | 120–136 | |||||
| sideoats grama | BOCU | Bouteloua curtipendula | 126–136 | – | ||
| 3 | 56–72 | |||||
| little bluestem | SCSC | Schizachyrium scoparium | 56–72 | – | ||
| 4 | 56–72 | |||||
| New Mexico feathergrass | HENE5 | Hesperostipa neomexicana | 56–72 | – | ||
| 5 | 56–64 | |||||
| black grama | BOER4 | Bouteloua eriopoda | 56–64 | – | ||
| 6 | 24–40 | |||||
| hairy grama | BOHI2 | Bouteloua hirsuta | 24–40 | – | ||
| 7 | 24–40 | |||||
| common wolfstail | LYPH | Lycurus phleoides | 24–40 | – | ||
| 8 | 16–24 | |||||
| sand bluestem | ANHA | Andropogon hallii | 16–24 | – | ||
| 9 | 16–24 | |||||
| threeawn | ARIST | Aristida | 16–24 | – | ||
| 10 | 8–24 | |||||
| sacahuista | NOMI | Nolina microcarpa | 8–24 | – | ||
| 11 | 0–25 | |||||
| silver bluestem | BOSA | Bothriochloa saccharoides | 0–10 | – | ||
| squirreltail | ELEL5 | Elymus elymoides | 0–10 | – | ||
| slim tridens | TRMUE | Tridens muticus var. elongatus | 0–5 | – | ||
| 12 | 0–16 | |||||
| sand dropseed | SPCR | Sporobolus cryptandrus | 0–16 | – | ||
| 13 | 0–16 | |||||
| James' galleta | PLJA | Pleuraphis jamesii | 0–16 | – | ||
|
Forb
|
||||||
| 14 | 8–24 | |||||
| pea | LATHY | Lathyrus | 8–24 | – | ||
| 15 | 0–16 | |||||
| bladderpod | LESQU | Lesquerella | 0–16 | – | ||
| 16 | 0–16 | |||||
| scarlet Indian paintbrush | CACO17 | Castilleja coccinea | 0–16 | – | ||
| 17 | 0–16 | |||||
| globemallow | SPHAE | Sphaeralcea | 0–16 | – | ||
| 18 | 0–16 | |||||
| milkvetch | ASTRA | Astragalus | 0–16 | – | ||
| 19 | 32–48 | |||||
| Forb, perennial | 2FP | Forb, perennial | 32–48 | – | ||
| 20 | 32–48 | |||||
| Forb, annual | 2FA | Forb, annual | 32–48 | – | ||
| 27 | 0–16 | |||||
| broom snakeweed | GUSA2 | Gutierrezia sarothrae | 0–16 | – | ||
|
Tree
|
||||||
| 21 | 24–40 | |||||
| juniper | JUNIP | Juniperus | 24–40 | – | ||
| 23 | 8–24 | |||||
| twoneedle pinyon | PIED | Pinus edulis | 8–24 | – | ||
|
Shrub/Vine
|
||||||
| 22 | 16–32 | |||||
| winterfat | KRLA2 | Krascheninnikovia lanata | 16–32 | – | ||
| 24 | 8–24 | |||||
| yucca | YUCCA | Yucca | 8–24 | – | ||
| 25 | 8–24 | |||||
| skunkbush sumac | RHTR | Rhus trilobata | 8–24 | – | ||
| 26 | 0–16 | |||||
| catclaw acacia | ACGR | Acacia greggii | 0–16 | – | ||
| 28 | 0–16 | |||||
| sagebrush | ARTEM | Artemisia | 0–16 | – | ||
Interpretations
Animal community
Habitat for Wildlife: This site provides habitat which supports a resident animal community that is characterized by mule deer, bobcat, spotted skunk, eastern cottontail, rock squirrel, rock mouse, great horned owl, scrub jay, canyon wren, prairie rattlesnake, and eastern fence lizard. Roadrunner, magpie, mockingbird, and loggerhead shrike utilize the juniper and shrub foliage for nesting.
Hydrological functions
The runoff curve numbers are determined by field investigations using hydrologic cover conditions and hydrologic soil groups.
Hydrologic Interpretations
Soil Series Hydrologic Group
Lacoca D
Latom D
Newkirk D
Recreational uses
This site has good aesthetic appeal and natural beauty with its large variety of plants that bloom from early spring to late fall. The physiography interrupts the “wide open space” of the plains. This site has fair suitability for camping, hiking and picnicking. Hunting is fair for deer and rabbits; quail hunting is fair to good. This site provides fair screening. Photography and birdwatching for small birds and raptors is fair.
Wood products
Juniper and pinyon provide limited fuel for firewood and a limited quantity of fence posts.
Other products
Grazing: This site can be grazed any season of the year by all classes and ages of livestock. Because of the steeper slopes and rock outcrop, younger livestock best utilize this site. Browsing animals should be considered because of the site’s potential to produce shrubs and forbs. Continuous yearlong or season-long (April-October) grazing by cattle will result in a decrease of species such as sideoats grama, little bluestem, New Mexico feathergrass, black grama, and winterfat. Species such as hairy grama, juniper, ring muhly, and broom snakeweed will increase. On sites with scattered juniper, continuous heavy grazing pressure will allow this tree to increase to the point that it appears dominant. A system of periodic grazing by domestic livestock, which varies the season of grazing and rest during successive years, will result in a healthy, well-balance plant community. Fall and winter rest will benefit shrubby species such as winterfat. Spring rest (April-June) will allow cool-season grasses to mature. Cattle show a definite seasonal preference for black grama, and usually utilize it heavily from January to March. A large variety of grasses, forbs, and shrubs provide well-balanced feed and good nutrition for all grazing animals. Ninety percent of the annual production is from species that provide forage for grazing animals.
Other information
Other Information: Guide to Suggested Initial Stocking Rate Acres per Animal Unit Month
Similarity Index Ac/AUM
100 - 76 3.4 – 5.4
75 – 51 4.3 – 7.8
50 – 26 5.6 – 11.2
25 – 0 11.3+
Supporting information
Inventory data references
Data collection for this site was performed in conjunction with the progressive soil surveys within the Pecos-Canadian Plains and Valleys--Major Land Resource Area 70 of New Mexico. This site has been mapped and correlated to soils in the following soil surveys: San Miguel, Quay, Guadalupe, De Baca, and Chaves.
Other references
References.
1. Johnsen, T.N., Jr. 1962. One-seeded juniper invasion of northern Arizona grasslands.
Ecological Monographs. 32:187-207.
2. Johnson, D.E., H. A. M. Mukhtar, R. Mapston, and R.R. Humphrey. 1962. The mortality of oak-juniper woodland species following a wildfire. Journal of Range Management 15: 201-205
3. Miller, R.F., and R.J. Tausch. 2001. The role of fire in pinyon and juniper woodlands: a
descriptive analysis. Pages 15–30 in K.E.M. Galley and T.P. Wilson (eds.). Proceedings
of the Invasive Species Workshop: the Role of Fire in the Control and Spread of Invasive
Species. Fire Conference 2000: the First National Congress on Fire Ecology, Prevention,
and Management. Miscellaneous Publication No. 11, Tall Timbers Research Station,
Tallahassee, FL.
4. Van Dyne, G.M., G.F. Payne, compilers. 1964. Grazing responses of western range plants. Bozeman, MT: Montana State College, Department of Animal and Range Sciences. 69 p.
Contributors
Christine Bishop
David Trujillo
Don Sylvester
Elizabeth Wright
John Tunberg
Approval
Kendra Moseley, 9/12/2023
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 | 09/13/2023 |
| 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:
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