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Ecological site R021XY102OR

SODIC FLAT 10+ PZ

Accessed: 11/24/2024

Home / Esd catalog / MLRA 021X / Ecological site R021XY102OR

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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.

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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.

Associated sites

R021XY104OR	SALINE MEADOW

R021XY104OR

SALINE MEADOW

Similar sites

R021XY104OR	SALINE MEADOW Lower sodium

R021XY104OR

SALINE MEADOW

Lower sodium

Table 1. Dominant plant species

Tree	Not specified
Shrub	Not specified
Herbaceous	Not specified

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Physiographic features

This site occurs in lake basins. This site may also occur on steeper slopes adjacent to basins where the wind has deposited soil particles which are high in sodium.

Table 2. Representative physiographic features

Landforms	(1) Basin floor
Elevation	1,219 – 1,433 m
Slope	0 – 1%
Aspect	Aspect is not a significant factor

Climatic features

The annual precipitation ranges from 10 to 14 inches, most of which occurs in the form of snow during the months of November through April with spring and fall rains. The soil temperature regime is mesic with the mean annual air temperature of about 47 degrees F. Temperature extremes range from 110 to -30 degrees F. The frost free period ranges from 70 to 110 days. The optimum period for plant growth is from mid-April to June.

Table 3. Representative climatic features

Frost-free period (average)	110 days
Freeze-free period (average)	0 days
Precipitation total (average)	356 mm

Bar

Line

Figure 2. Monthly average minimum and maximum temperature

Soil features

The soils of this site are strongly or very strongly alkaline. The presence of sodium and salts limit the use of these soils. The soils are very deep to bedrock but typically have a water table at or near the surface durng the spring. Because of the sodium, soil structure is poor and puddling of the surface layer is common. Along with the sodium, salts are usually present and plant available water is dramatically reduced. In some cases the soils have a black, crusted surface. This condition supports little or no vegetation. The soils are somewhat poorly or poorly drained. Typically the surface is silt loam with a clay loam or clay subsoil. Permeability is moderate to slow. Runoff is very slow. Erosion hazard from water is slight but wind erosion can be a concern where the surface soil is exposed and is dry.

Table 4. Representative soil features

Surface texture	(1) Silt loam
Family particle size	(1) Clayey
Drainage class	Somewhat poorly drained to poorly drained
Permeability class	Slow to moderate
Soil depth	152 cm

Ecological dynamics

If the condition of the site deteriorates as a result of overgrazing, bisin wildrye will decrease while inland saltgrass will become the dominant grass. Further deterioration will reduce soil cover and accelerate soil moisture evaporation leading to an increased concentration of salts and alkali on the soil surface.

The typical plant composition of this site results from poor soil drainage and accumulations of salts and sodium. Where small elevational increases occur and drainage is imporved, there is an increase in plants less tolerant of salts and sodium.

State and transition model

Custom diagram

Standard diagram

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

Ecosystem states

1. HCPC, LECI4-DISP/SAVE4

State 1 submodel, plant communities

1.1. HCPC, LECI4-DISP/SAVE4

State 1
HCPC, LECI4-DISP/SAVE4

Community 1.1
HCPC, LECI4-DISP/SAVE4

The potential native plant community is dominated by basin wildrye, black greasewood and inland saltgrass. Gray rabbitbrush, alkali bluegrass, sedges and rushes are common. Vegetative composition of the community is approximately 85% grasses, 5% forbs, and 10% shrubs.

Figure 3. Annual production by plant type (representative values) or group (midpoint values)

Table 5. Annual production by plant type

Plant type	Low (kg/hectare)	Representative value (kg/hectare)	High (kg/hectare)
Grass/Grasslike	1076	1421	1765
Shrub/Vine	118	185	252
Forb	67	101	135
Total	1261	1707	2152

Figure 4. Plant community growth curve (percent production by month). OR5511, D21 Low Elev., NA, Good Condition. RPC Growth Curve.

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	15	30	50	5	0	0	0	0	0	0

Additional community tables

Table 6. Community 1.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production (kg/hectare)	Foliar cover (%)
Grass/Grasslike
1	Dominant deep rooted perennial grasses			841–1177
	basin wildrye	LECI4	Leymus cinereus	841–1177	–
2	Sub-dominant deep rooted perennial grasses			84–252
	saltgrass	DISP	Distichlis spicata	84–252	–
3	Dominant shallow rooted perennial grasses			118–252
	Sandberg bluegrass	POSE	Poa secunda	118–252	–
5	Other perennial grasses			34–84
	sedge	CAREX	Carex	0–6	–
	rush	JUNCU	Juncus	0–6	–
Forb
7	Dominant perennial shrubs			67–135
	common yarrow	ACMI2	Achillea millefolium	17–34	–
	fleabane	ERIGE2	Erigeron	17–34	–
	povertyweed	IVAX	Iva axillaris	17–34	–
	pepperweed	LEPID	Lepidium	17–34	–
Shrub/Vine
12	Sub-dominant evergreen shrubs			34–84
	rubber rabbitbrush	ERNA10	Ericameria nauseosa	34–84	–
13	Dominant deciduous (or 1/2 shrubs) shrubs			84–168
	greasewood	SAVE4	Sarcobatus vermiculatus	84–168	–

Interpretations

Animal community

When located near water, this site provides food and cover for mule deer and quail.

Hydrological functions

The soils are typically in hydrologic group D.

Other products

This site is suited to grazing by livestock in most seasons under a planned grazing system. This site can be damages if heavily grazed during spring and early summer.

Other information

The soils of this site typically reflect hydric soil characteristics. Chemcial conditions in the soil may make it corrosive to concrete and steel. This site is not well suited to reseeding. Salt concentrations inhibit germination of most presently available species.

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)	Jeff Repp
Contact for lead author	Oregon NRCS State Rangeland Management Specialist
Date	08/21/2012
Approved by	Bob Gillaspy
Approval date
Composition (Indicators 10 and 12) based on	Annual Production

Indicators

Number and extent of rills:
None, slight sheet & rill erosion hazard
Presence of water flow patterns:
None
Number and height of erosional pedestals or terracettes:
None
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
5-25% black alkali spots are devoid of vegetation
Number of gullies and erosion associated with gullies:
None
Extent of wind scoured, blowouts and/or depositional areas:
None, slight wind erosion hazard: severe when soil is exposed and dry
Amount of litter movement (describe size and distance expected to travel):
Fine to moderately coarse - limited movement
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Moderately resistant to erosion: aggregate stability = 3-4
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
Very deep strongly or very strongly alkaline, somewhat poorly or poorly drained loams, silt loams, and silty clay loams: Low OM (1-2%)
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
High ground cover (75-85%) and gentle slopes (0-1%) effectively limits rainfall impact and overland flow, infiltration can be limited by excess thatch
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:
Basin wildrye > Inland saltgrass > Alkali bluegrass = Black greasewood > other shrubs = other grasses > forbs

Sub-dominant:

Other:

Additional:
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
Normal decadence and mortality expected
Average percent litter cover (%) and depth ( in):
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
Favorable: 2200, Normal: 1500, Unfavorable: 1000 lbs/acre/year at high RSI (HCPC)
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 brush species will increase with deterioration of plant community. Cheatgrass and Medusahead invade sites that have lost deep rooted perennial grass functional groups.
Perennial plant reproductive capability:
All species should be capable of reproducing annually

Download reference sheet