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UNITED STATES DEPARTMENT OF AGRICULTURE
NATURAL RESOURCES CONSERVATION SERVICE

ECOLOGICAL SITE DESCRIPTION
ECOLOGICAL SITE CHARACTERISTICS

Site Type: Rangeland

Site Name: Loamy

Site ID: R070DY153NM

Major Land Resource Area: 070D - Southern Desert Foothills


Physiographic Features
This site occurs on level to gently sloping plains and terraces at elevations ranging from 4,000 to 7,000 feet above sea level. Slopes vary from 0 to 9 percent but average less than 5 percent.


Land Form: (1) Plain
(2) Terrace
Minimum Maximum
Elevation (feet): 4000 7000
Slope (percent): 0 9
Water Table Depth (inches):
Flooding:
         Frequency:
         Duration: None None
Ponding:
         Depth (inches):
         Frequency:
         Duration: None None
Runoff Class: Negligible Medium
Aspect: No Influence on this site
Climatic Features
The climate of this area is “semi-arid continental.”

Annual average precipitation ranges from 11 to 19 inches. Variations of 5 inches, more or less, are not uncommon. Approximately 70 percent of the precipitation occurs from May through October. Most of the summer rain comes in the form of high-intensity, short- uration thunderstorms. Winter moisture is usually negligible.

Temperatures are characterized by distinct seasonal changes and large diurnal temperature changes. The average annual temperature ranges from 55 degrees F to 60 degrees F, with extremes of 20 degrees F below zero in the winter to 110 degrees F in the summer not uncommon.

The average frost-free season is 170 to 189 days. The last killing frost is in early April and the first killing frost is in mid October.

Both temperature and precipitation favor warm-season perennial plant communities. At higher elevations, 40 percent of the precipitation is favorable for cool-season growth. Strong winds from the west and southwest blow from February through June. This accelerates the drying of the soil during a critical growth period for most cool-season plants.

Climate data was obtained from http://www.wrcc.sage.dri.edu/summary/climsmnm.html web site.
Data interpreted utilizing NM NRCS Climate Summarizer spreadsheet.


Minimum Maximum
Frost-free period (days): 170 189
Freeze-free period (days): 192 211
Mean annual precipitation (inches): 11.0 19.0
Monthly precipitation (inches) and temperature (°F):
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Precip. Min. 0.08 0.12 0.08 0.07 0.38 0.45 1.13 1.5 0.85 0.34 0.01 0.08
Precip. Max. 0.78 0.82 0.75 0.85 1.98 2.11 3.49 3.97 3.8 2.07 0.87 0.86
Temp. Min. 24.5 27.0 31.9 38.9 47.3 55.5 59.5 58.4 52.0 42.1 31.0 24.9
Temp. Max. 55.6 59.5 65.7 73.6 80.8 88.6 88.3 86.4 81.2 73.9 64.0 56.6
Climate Stations: (1) 292865, Elk 2E. Period of record 1895 - 2007
(2) 294112, Hope. Period of record 1919 - 2007

Influencing Water Features
This site is not influenced by water from a wetland or stream.

Wetland Description: System Subsystem Class
(Cowardin System) None N/A N/A

Representative Soil Features
The soils on this site are moderately deep to deep, well drained. The surface textures are loam, silt loams, silty clay loams and fine sandy loams. Permeability is slow to moderately rapid and available water-holding capacity is medium to high with surface runoff medium. The water and wind erosion hazard is high.


Predominant Parent Materials:
           Kind: Alluvium
           Origin:
Surface Texture: (1) Loam
(2) Silt loam
(3) Silty clay loam
Subsurface Texture Group: Clayey
Minimum Maximum
Surface Fragments <=3" (% Cover):
Surface Fragments > 3" (% Cover):
Subsurface Fragments <=3" (% Volume):
Subsurface Fragments > 3" (% Volume):
Drainage Class: Well drained To Well drained
Permeability Class: Slow To Moderately rapid
Minimum Maximum
Depth (inches): 20 40
Electrical Conductivity (mmhos/cm): 0 2
Sodium Absorption Ratio:
Calcium Carbonate Equivalent (percent):
Soil Reaction (1:1 Water): 7.4 8.4
Soil Reaction (0.01M CaCl2):
Available Water Capacity (inches): 6.0 12.0
Plant Communities
Ecological Dynamics of the Site
Overview
This site is associated with Limestone Hills and Shallow sites. Loamy sites in CP-4 typically occur as elongated units on valley terraces and fans below Limestone Hills, or adjacent to, but topographically lower than Shallow sites. The historic plant community of the Loamy site has the aspect of a grassland with a few shrubs and succulents scattered across the site. Composition and production vary with elevation. In the historic plant community, blue grama, black grama, and tobosa are the dominant grasses. This site is susceptible to encroachment by shrubs, especially juniper and broom snakeweed. Dispersal of shrub seeds, loss of grass cover and resulting competition for resources by shrubs, and a decrease in natural fire frequency may facilitate the transition to a state that is dominated by shrubs. Persistent loss of grass cover, increased overland water flow, and resulting erosion may cause the transition to a Gullied State.



Historic Climax Plant Community
Grassland: At lower elevations blue grama, black grama, and tobosa are the dominant grasses, with sideoats grama, vine mesquite, and plains lovegrass as sub-dominants. At higher elevations, blue grama, sideoats grama, and western wheatgrass dominate, with vine mesquite, plains lovegrass, black grama, and tobosa as sub-dominants. Continuous heavy grazing will cause a decrease in sideoats grama, western wheatgrass, black grama, vine mesquite, and fourwing saltbush. At higher elevations this may result in a community dominated by blue grama. At lower elevations, tobosa and threeawns may dominate. A community of perennial grasses with broom snakeweed as the sub-dominant component may occur in response to overgrazing, or as a result of late fall/early spring moisture following drought. 6 Shrubs and succulents common to the site include yucca, fourwing saltbush, sumac species, juniper, broom snakeweed, and cholla.

Diagnosis: Grass cover is uniform and evenly distributed. Litter cover is high, averaging 25 percent. Shrub/succulent cover is low averaging only 2 percent. Evidence of erosion such as large water flow patterns, rills and gullies are infrequent.

Other grasses which would appear on this site include:
bottlebrush squirreltail, galleta, alkali sacaton, hairy grama, mat muhly, ring muhly, green sprangletop, Hall’s panicum, plains bristlegrass, little bluestem, silver bluestem, Indiangrass, fluffgrass, buffalograss, wolftail, tridens spp., and needle grass.

Other shrubs include:
cholla, juniper, pinyon, creosotebush, oak spp., broom baccharis, pricklypear, Apacheplume, dalea spp., winterfat, and algerita.

Other forbs include:
wooly loco, wooly Indianwheat, cudweed, thistles, annual sunflowers, mullin, wildbuckwheat spp., nightshade spp., milkweed spp., and bladderpod.




Historic Climax Plant Community Plant Species Composition:
Grass/Grasslike Annual Production
in Pounds Per Acre
Group Group Name Common Name Scientific Name Low High
1 58 403
     blue gramaBouteloua gracilis58403
2 58 173
     sideoats gramaBouteloua curtipendula58173
3 115 403
     black gramaBouteloua eriopoda115403
4 115 403
     tobosagrassPleuraphis mutica115403
5 35 58
     sand dropseedSporobolus cryptandrus3558
6 58 115
     vine mesquitePanicum obtusum58115
7 115 173
     western wheatgrassPascopyrum smithii115173
8 35 58
     threeawnAristida3558
9 35 58
     burrograssScleropogon brevifolius3558
10 58 115
     plains lovegrassEragrostis intermedia58115
11 35 58
     Graminoid (grass or grass-like)3558
Forb Annual Production
in Pounds Per Acre
Group Group Name Common Name Scientific Name Low High
12 12 35
     dwarf desertpeonyAcourtia nana1235
13 35 58
     crotonCroton3558
     rabbitbushEricameria bloomeri3558
     ragwortSenecio3558
     globemallowSphaeralcea3558
14 12 35
     Forb (herbaceous, not grass nor grass-like)1235
Shrub/Vine Annual Production
in Pounds Per Acre
Group Group Name Common Name Scientific Name Low High
15 35 58
     yuccaYucca3558
16 35 58
     fourwing saltbushAtriplex canescens3558
17 23 58
     catclaw acaciaAcacia greggii2358
18 23 58

19 23 58
     broom snakeweedGutierrezia sarothrae2358
20 12 35
     Shrub, deciduous1235
Annual Production by Plant Type:
Annual Production (lbs/AC)
Plant Type Low Representative Value High
Forb 64 92 120
Grass/Grasslike 624 897 1170
Total:
688
989
1290
Structure and Cover:
Ground Cover (%)
Vegetative Cover Non-Vegetative Cover
Grass/ Grasslike Forb Shrub/ Vine Tree Non-Vascular Plants Biological Crust Litter Surface Fragments > 1/4 & <= 3" Surface Fragments > 3" Bedrock Water Bare Ground
            25 to 25          32 to 32 
 

Plant Growth Curve:
Growth Curve Number: NM4603
Growth Curve Name: HCPC
Growth Curve Description: Mixed short/mid warm-season grassland with scattered shrubs and half-shrubs and a fluctuating forb component.
Percent Production by Month
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
0 0 3 5 10 10 25 30 12 5 0 0

Shrub-Dominated
Additional States:

Shrub Dominated: This state is characterized by the predominance of shrubs with perennial grasses as the subordinate component. Grass cover varies inversely with shrub density. Typically juniper and broom snakeweed are the dominant shrubs. Juniper tends to dominate at mid-to upper elevations with blue grama as the subordinate grass component. Broom snakeweed may come to dominate across most elevation ranges with either blue grama or tobosa as the subordinate grass species.

Diagnosis: Shrubs are found at increased densities relative to the Grassland State. Grass cover is variable ranging from fairly uniform to patchy with large connected bare areas present. Blue grama or tobosa are the dominant grasses, and threeawns, ring muhly, cholla and prickly pear typically increase in representation.

Transition to Shrub Dominated State (1a): Seed dispersal of shrubs, loss of grass cover, resource competition between shrubs and grasses, and lack of fire are all believed to facilitate the 12 encroachment of shrubs. Wildlife and livestock (especially birds and sheep) are instrumental in the dispersal of juniper seed. 3, 4 Broom snakeweed produces abundant light seed and the dispersal mechanism is mainly wind.5 Sites that receive above-average late fall/early spring moisture following drought,6 or that have been overgrazed 7may be quickly invaded by broom snakeweed. Drought is detrimental to grasses and the establishment of juniper seedlings, but larger, established trees may gain a competitive edge facilitating juniper dominance. Competition is an important constraint on the establishment of shrub seedlings, because grass roots preempt resources, such as water.2 However, during wet years shrub seedlings may establish in good stands of grass due to reduced moisture competition. Once shrub seedlings become established, and if their roots are capable of extending below this zone, competition for soil moisture declines.2 Overgrazing may facilitate the establishment of shrub seedlings by providing competition free areas, but livestock exclusion alone would not prevent shrub expansion. Historically, periodic fire may have helped to suppress shrubs by completely killing some species, disrupting seed production cycles, and suppressing the establishment of shrub seedlings.1

Key indicators of approach to transition:
* Decrease or change in composition or distribution of grass cover.
* Increase in size and frequency of bare patches.
* Increase in amount of shrub seedlings.

Transition back to Grassland (1b) Brush control is necessary to initiate the transition back to the grassland state. Prescribed grazing will help ensure adequate rest following brush control and will assist in the establishment and maintenance of grass cover. Once the transition back to the Grassland State is achieved, prescribed fire may help in maintaining grass dominance.



Guillied State
Gullied State: Loss of grass cover, accelerated erosion, and gully formation characterize this state. Blue grama or tobosa are typically the dominant grasses. Shrub densities reflect either those of the Grassland State or The Shrub-Dominated State, depending on the transition pathway.

Diagnosis: Grass cover is patchy with large bare areas present. Erosion is evident by the presence of water flow patterns, rills and gullies.

Transition to Gullied State (2,3a): Transitions to the Gullied State occur in response to the loss of grass cover, and subsequent erosion. As grass cover is reduced, organic matter, infiltration, and soil surface stability decrease.

Key indicators of approach to transition:
* Reduction in grass cover (on site, or on surrounding uplands).
* Increase in size and frequency of bare patches.
* Presence of litter dams, water flow patterns, rills and gullies.

Transition back to Grassland (3b) Erosion control structures or shaping and filling gullies may help regain natural flow patterns and allow natural revegetation to take place. Prescribed grazing will help ensure proper forage utilization and reduce grass loss due to overgrazing. Brush control will be necessary if from transition (2).


Ecological Site Interpretations
Animal Community:
Habitat for Wildlife:
This site provides habitat which supports a resident animal community that is characterized by pronghorn antelope, sparrow hawk, badger, black-tailed jackrabbit, black- tailed prairie dog, Botta’s pocket gopher, burrowing owl, roadrunner, cactus wren, coyote, bobcat, scaled quail, horned lark, great plains toad, and horned lizard. Mule deer use this site seasonally as do mourning dove.

Plant Preference by Animal Kind:
Animal Kind: mature antelope Antelope
Common Name Scientific Name Plant Part J F M A M J J A S O N D
fourwing saltbush Atriplex canescens Leaves D D D D D D D D D D D D
globemallow Sphaeralcea Entire plant U U D D D D D D U U U U
Animal Kind: mature cow Cattle
Common Name Scientific Name Plant Part J F M A M J J A S O N D
fourwing saltbush Atriplex canescens Leaves P P P P P D D D D D D P
sideoats grama Bouteloua curtipendula Entire plant P P P P P P P P P P P P
blue grama Bouteloua gracilis Entire plant D D D D P P P P P D D D
vine mesquite Panicum obtusum Entire plant D D D D D D D D D D D D
western wheatgrass Pascopyrum smithii Entire plant D D P P P D D D D D D D
Animal Kind: mature sheep Sheep
Common Name Scientific Name Plant Part J F M A M J J A S O N D
fourwing saltbush Atriplex canescens Leaves P P P P P D D D D D D P
sideoats grama Bouteloua curtipendula Entire plant P P P P P P P P P P P P
black grama Bouteloua eriopoda Entire plant P P P D D D D D D D P P
blue grama Bouteloua gracilis Entire plant D D D D P P P P P D D D
western wheatgrass Pascopyrum smithii Entire plant U U D D D D D D D D D U
Legend:          P = Preferred     D = Desirable          U = Undesirable     N = Not consumed          E = Emergency     T = Toxic     X = Used,      but degree of utilization unknown

Hydrology Functions:
The runoff curve numbers are determined by field investigations using hydrologic cover conditions and hydrologic soil groups.

Hydrologic Interpretations
Soil Series-------Hydrologic Group
Ancho-------------------B
Cale--------------------B
Cuevoland---------------B
Gabaldon----------------B
Jarita------------------C
Kerrick-----------------B
La Fonda----------------B
Montecito---------------C
Pena--------------------B
Reeves Variant----------B
Ruidoso-----------------C
Rumuda------------------C
Shanta------------------B
Shanta Variant----------B

Recreational Uses:
Recreation potential is limited largely by the lack of water and firewood. It is fairly suited for camping, hiking, and picnicking. The wide-open spaces and many colorful wildflowers that bloom during years of good moisture enhance esthetic appeal. Antelope, quail, dove and varmint hunting is good. Trapping for fur-bearing animals is good.

Wood Products:
At higher elevations pinyon and juniper offers firewood and fencing materials. Century plant and cholla skeletons are used for ornamental purposes.

Other Products:
Grazing:
This site is suited for grazing by all kinds and classes of livestock during all seasons of the year. However, because of the large percentage of grass in the potential plant community, this site is best suited for some type of cattle operation. Continuous yearlong or growing season grazing will cause a decrease in sideoats grama, black grama, vine-mesquite, and fourwing saltbush. A corresponding increase in broom snakeweed, cholla, sand dropseed, threeawns, burrograss, and forbs will follow. This site will respond well to a planned grazing system that rotates the season of use. Under retrogression, an increase in woody plants at lower elevations and forbs will cause a decrease in total ground cover. This can cause severe wind and water erosion, both rill and gully. In severe cases of gully erosion, expensive structural measures will be required to restore this site.
Other Information:
Guide to Suggested Initial Stocking Rate Acres per Animal Unit Month

Similarity------------Index Ac/AUM
100 - 76---------------2.0 – 4.5
75 – 51----------------3.5 – 6.0
50 – 26----------------5.0 – 9.0
25 – 0-----------------10.0+


Supporting Information
Associated Sites:
Site Name Site ID Site Narrative

Similar Sites:
Site Name Site ID Site Narrative

State Correlation:
This site has been correlated with the following states:
NM    
Inventory Data References:
Data collection for this site was done in
conjunction with the progressive soil surveys
within the Pecos-Canadian Plains and Valleys Major Land Resource Area of New Mexico (MLRA 70).

This site has been mapped and correlated with soils in the following soil surveys:
Otero, Eddy, Chaves, Lincoln


Type Locality:
Relationship to Other Established Classifications:
Other References:
References

1. Brooks, M.L. and D.A. Pyke. 2001. Invasive plants and fire in the deserts of North America.Pages 1–14 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.

2. Johnsen, T. N., Jr. 1962. One-seeded juniper invasion of northern Arizona grasslands. Ecological Monographs. 32:187-207.

3. Parker, K. W. 1945. Juniper comes to the grassland. American Cattle Producer. 27: 12- 14.

4. Phillips, Frank J. 1910. The dissemination of junipers by birds. Forestry Quarterly.
8: 60-73. (From Expt. Sta. Rec. 22: 644.)



Site Description Approval:
Author Date Approval Date
Don Sylvester 2/2/1982 Donald H. Fulton 3/3/1982

Site Description Revision Approval:
Author Date Approval Date
John Tunberg 4/22/2008 John Tunberg 4/22/2008
David Trujillo 10/29/2003 George Chavez 10/29/2003
Elizabeth Wright 7/10/2002 George Chavez 10/29/2003

Reference Sheet

Author(s)/participant(s):

Contact for lead author:

Date:               MLRA: 070D               Ecological Site: Loamy R070DY153NM     This must be verified based on soils and climate (see Ecological Site Description). Current plant community cannot be used to identify the ecological site.

Composition (indicators 10 and 12) based on:       Annual Production,       Foliar Cover,       Biomass

Indicators. For each indicator, describe the potential for the site. Where possible, (1) use numbers, (2) include expected range of values for above- and below-average years for each community and natural disturbance regimes within the reference state, when appropriate and (3) cite data. Continue descriptions on separate sheet.

1. Number and extent of rills:
2. Presence of water flow patterns:
3. Number and height of erosional pedestals or terracettes:
4. Bare ground from Ecological Site Description or other studies (rock, litter, standing dead, lichen, moss, plant canopy are not bare ground):
5. Number of gullies and erosion associated with gullies:
6. Extent of wind scoured, blowouts and/or depositional areas:
7. Amount of litter movement (describe size and distance expected to travel):
8. Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
9. Soil surface structure and SOM content (include type and strength of structure, and A-horizon color and thickness):
10. Effect on plant community composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
11. Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
12. Functional/Structural Groups (list in order of descending dominance by above-ground weight using symbols: >>, >, = to indicate much greater than, greater than, and equal to) with dominants and sub-dominants and "others" on separate lines:
      Dominant:
      Sub-dominant:
      Other:
      Additional:
13. Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
14. Average percent litter cover (%) and depth ( inches):
15. Expected annual production (this is TOTAL above-ground production, not just forage production:
16. 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 indicator, we are describing what in NOT expected in the reference state for the ecological site:
17. Perennial plant reproductive capability:
 

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