Natural Resources
Conservation Service
Ecological site R010XB044OR
JD Droughty South 9-12 PZ
Accessed: 10/30/2024
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.
Associated sites
| R010XB064OR |
JD North 9-12 PZ The site is on droughty north slopeswith Bluebunch wheatgrass predominant. |
|---|
Similar sites
| R010XB041OR |
JD Clayey South 9-12 PZ Site is on Clayey South slopes with a 9-12" precipitation zone. |
|---|---|
| R010XB052OR |
JD Droughty Shallow South 9-12 PZ Site is a droughty south with shallow soils. |
Table 1. Dominant plant species
| Tree |
Not specified |
|---|---|
| Shrub |
Not specified |
| Herbaceous |
Not specified |
Physiographic features
This site occurs on southerly exposures of low elevation terraces composed of early Cenezoic tuffaceous sediments. Slopes typically range from 15 to 60% with slopes. Elevation varies from 1300 to 2400 feet.
Table 2. Representative physiographic features
| Landforms |
(1)
Hill
(2) Terrace |
|---|---|
| Flooding frequency | None |
| Ponding frequency | None |
| Elevation | 1,300 – 2,400 ft |
| Slope | 15 – 60% |
| Ponding depth |
Not specified |
| Water table depth | 72 in |
| Aspect | SE, S, W |
Climatic features
Elevation and aspect affect precipitation and the relative effectiveness of the precipitation and temperatures. Temperature changes can occur rapidly. In addition, the topography also results in localized cold air drainages, along with occasional cold air entrapment and inversions in the valleys. Annual snowfall is 13 inches to 17 inches, with most coming in the winter and spring. Snow cover is of short duration and melts quickly at low elevations.
Table 3. Representative climatic features
| Frost-free period (average) | 150 days |
|---|---|
| Freeze-free period (average) | 209 days |
| Precipitation total (average) | 12 in |
Figure 2. Monthly precipitation range
Figure 3. Monthly average minimum and maximum temperature
Influencing water features
Soil features
Soils on this site are Mollisols with predominantly gravelly loam over clay textures. The soils are very deep with fine textures and well drained. These soils are formed from Cenezoic Tuffaceous Sediments that are weathered from John Day (mid-Oligocene) or Clarno (late Eocene) geological formations. Cobbles are present. The soils are generally aridic. The major taxonomic units correlated to this site include fine, smectitic, mesic Vertic Palexerolls.
Table 4. Representative soil features
| Surface texture |
(1) Loam (2) Gravelly loam |
|---|---|
| Family particle size |
(1) Clayey |
| Drainage class | Well drained |
| Permeability class | Very slow |
| Soil depth | 60 in |
| Surface fragment cover <=3" | 20% |
| Surface fragment cover >3" | 20% |
| Available water capacity (0-40in) |
6 – 9 in |
| Calcium carbonate equivalent (0-40in) |
5% |
| Electrical conductivity (0-40in) |
Not specified |
| Sodium adsorption ratio (0-40in) |
Not specified |
| Soil reaction (1:1 water) (0-40in) |
6.6 – 7.8 |
| Subsurface fragment volume <=3" (Depth not specified) |
15% |
| Subsurface fragment volume >3" (Depth not specified) |
25% |
Ecological dynamics
The interpretative plant community for this site is the Historic Climax Plant Community (HCPC). Grasses with few forbs and shrubs dominate this plant community. Fluctuations in species composition and relative production may change from year to year dependent upon abnormal precipitation or other climatic factors. The historic climax plant community has been determined by study of rangeland relic areas, or areas protected from excess disturbance. Trends in plant communities going from heavily grazed areas to lightly grazed areas, seasonal pastures, and historical accounts have also been used.
Pathways for the state and transition model are as follows:
1 - Over grazing w/o frequent fire
2 - Proper grazing or rest
3 - Continued mis-management with fire
4 - Rest and re-seed, time
State and transition model
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
State 1 submodel, plant communities
State 2 submodel, plant communities
State 1
HCPC: ACTH7-PSSP6
Community 1.1
HCPC: ACTH7-PSSP6
Figure 4. JD Droughty South 9-12, State A
HCPC - Dominated by Thurber Needlegrass and Bluebunch Wheatgrass. This plant community evolved with limited grazing by large herbivores and with fire frequency of every 5 to 15 years. About 5% of the plant composition is made up of forbs and 8% of shrubs. Bluebunch Wheatgrass increases with clay surface and decreases in gravel.
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) |
|---|---|---|---|
| Grass/Grasslike | 696 | 870 | 1044 |
| Shrub/Vine | 64 | 80 | 96 |
| Forb | 40 | 50 | 60 |
| Total | 800 | 1000 | 1200 |
Figure 6. Plant community growth curve (percent production by month). OR4231, B10 JD Dr South 9-12 A. JD Dr South 9-12 A, 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 | 5 | 20 | 25 | 30 | 10 | 5 | 0 | 0 | 5 | 0 | 0 |
State 2
Cheatgrass/Medusahead/Broom Snakeweed
Community 2.1
Cheatgrass/Medusahead/Broom Snakeweed
Figure 7. JD Droughty South 9-12" PZ, State C
A community dominated by Broom Snakeweed, Cheatgrass and Medusahead. Continued mismanagement of this site with fire disturbance has caused the deterioration. The site has passed a threshold and cannot naturally return to a previous state. Mechanical manipulation is needed to bring this site back to a productive state.
Figure 8. Annual production by plant type (representative values) or group (midpoint values)
Table 6. Annual production by plant type
| Plant type | Low (lb/acre) |
Representative value (lb/acre) |
High (lb/acre) |
|---|---|---|---|
| Grass/Grasslike | 100 | 200 | 300 |
| Shrub/Vine | 98 | 196 | 294 |
| Forb | 2 | 4 | 6 |
| Total | 200 | 400 | 600 |
Figure 9. Plant community growth curve (percent production by month). OR4233, B10 JD South 9-12 C. GUSA2/BRTE/TACA8.
| 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 | 10 | 15 | 25 | 30 | 15 | 0 | 0 | 5 | 0 | 0 | 0 |
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 | 820–1150 | |||||
| Thurber's needlegrass | ACTH7 | Achnatherum thurberianum | 600–800 | – | ||
| bluebunch wheatgrass | PSSPS | Pseudoroegneria spicata ssp. spicata | 200–300 | – | ||
| Indian ricegrass | ACHY | Achnatherum hymenoides | 20–50 | – | ||
| 2 | 40–140 | |||||
| sand dropseed | SPCR | Sporobolus cryptandrus | 20–100 | – | ||
| Sandberg bluegrass | POSE | Poa secunda | 20–40 | – | ||
|
Forb
|
||||||
| 3 | 7–50 | |||||
| milkvetch | ASTRA | Astragalus | 3–5 | – | ||
| prairie clover | DALEA | Dalea | 1–3 | – | ||
| buckwheat | ERIOG | Eriogonum | 1–3 | – | ||
| desertparsley | LOMAT | Lomatium | 1–3 | – | ||
| common yarrow | ACMI2 | Achillea millefolium | 1–3 | – | ||
|
Shrub/Vine
|
||||||
| 4 | 65–80 | |||||
| broom snakeweed | GUSA2 | Gutierrezia sarothrae | 20–80 | – | ||
| western juniper | JUOC | Juniperus occidentalis | 5–10 | – | ||
| basin big sagebrush | ARTRT | Artemisia tridentata ssp. tridentata | 5–10 | – | ||
| rabbitbrush | CHRYS9 | Chrysothamnus | 5–10 | – | ||
Table 8. Community 2.1 plant community composition
| Group | Common name | Symbol | Scientific name | Annual production (lb/acre) | Foliar cover (%) | |
|---|---|---|---|---|---|---|
|
Grass/Grasslike
|
||||||
| 1 | 1–8 | |||||
| sand dropseed | SPCR | Sporobolus cryptandrus | 0–8 | – | ||
| bluebunch wheatgrass | PSSPS | Pseudoroegneria spicata ssp. spicata | 0–4 | – | ||
| 2 | 100–160 | |||||
| medusahead | TACA8 | Taeniatherum caput-medusae | 120–160 | – | ||
| cheatgrass | BRTE | Bromus tectorum | 80–120 | – | ||
|
Forb
|
||||||
| 3 | 1–4 | |||||
| common yarrow | ACMIM2 | Achillea millefolium var. millefolium | 0–4 | – | ||
| buckwheat | ERIOG | Eriogonum | 0–4 | – | ||
|
Shrub/Vine
|
||||||
| 4 | 90–150 | |||||
| broom snakeweed | GUSA2 | Gutierrezia sarothrae | 80–120 | – | ||
| basin big sagebrush | ARTRT | Artemisia tridentata ssp. tridentata | 40–80 | – | ||
| western juniper | JUOC | Juniperus occidentalis | 20–40 | – | ||
Interpretations
Animal community
Grazing
Livestock grazing is suitable for this site as long as management objectives include the improvement or maintenance of this site. It is easy to overuse this site and cause a shift in vegetation that is difficult to change. This site has the potential to produce a large amount of high quality forage. Management should be aimed at harvesting the forage as quickly as possible, letting the site recover from the grazing event prior to fall dormancy.
Initial stocking rates will be determined with the landowner or decisionmaker. They will be based on past use histories and type and condition of the vegetation. Calculations used to determine an initial starting stocking rate will be based on forage preference ratings.
Wildlife
The main wildlife species of concern on this site are large herbivores. These are mule deer and elk. These wildlife species can possibly overuse this site before the time cattle or sheep are planned to be grazed. Being an open grassland, this site is home to a variety of small herbivores, birds, and their associated predators. This site is mainly a foraging area for the larger wildlife. No threatened or endangered wildlife species rely on this site for any of their habitat requirements.
Hydrological functions
The site has a high potential in low seral condition to produce significant run-off to receiving waters. The hydrology of this site is characterized by high intensity thunderstorms during the summer months and by low intensity frontal storms during the winter.
Recreational uses
None
Wood products
No wood products are associated with this site.
Other products
None
Other information
Increase in western juniper and the subsequent competition for moisture will lead to a reduction of available forage. Overgrazing can easily reduce ground cover and accelerate soil loss. Improving infiltration and permeability, and reducing runoff should be the immediate goal of juniper control.
Supporting information
Type locality
| Location 1: Wheeler County, OR | |
|---|---|
| Township/Range/Section | T7S R19E S34 |
| Longitude | 120° 27′ 19″ |
| General legal description | USGS Quad; Clarno. John Day Fossil Beds National Monument, Clarno Unit, approximately 300 feet east and 1200 feet south of the NW corner of section 34, T.7S, R.19E. |
| Location 2: Grant County, OR | |
| Township/Range/Section | T11S R26E S5 |
| Latitude | 44° 38′ 45″ |
| Longitude | 119° 37′ 40″ |
| General legal description | USGS Quad: Mt. Misery, Oregon. Foree Unit, John Day Fossil Beds National Monument. (80% SI) |
| Location 3: Grant County, OR | |
| Township/Range/Section | T12S R26E S6 |
| Latitude | 44° 33′ 30″ |
| Longitude | 119° 39′ 10″ |
| General legal description | USGS Quad; Picture Gorge West, Oregon. John Day Fossil Beds National Monument. (80% SI) |
Other references
Soil Conservation Service, Relative Forage Preference of Plants for Grazing Use by Season, Range Technical Note No. 16, 1982.
Western Regional Climate Center, NOAA, National Weather Service, Portland, OR. Web site - http://nimbo.wrh.noaa.gov/Portland/climate.html.
Natural Vegetation of Oregon and Washington, Jerry F. Franklin and C. T. Dyrness.
The Ecological Provinces of Oregon, E. William Anderson, Michael M. Borman, and William C. Krueger.
Contributors
CB
Ed Petersen, Rangeland Management Specialist, John Day Field Office, And Alan Bahn, Rangeland Management Specialist, Baker City Field Office
JPR
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 and Bruce Frannsen |
|---|---|
| Contact for lead author | State Rangeland Management Specialist for NRCS - Oregon |
| Date | 08/06/2012 |
| Approved by | Bob Gillaspy |
| Approval date | |
| Composition (Indicators 10 and 12) based on | Annual Production |
Indicators
-
Number and extent of rills:
None to very few on steeper slopes, moderate sheet & rill erosion hazard -
Presence of water flow patterns:
None to very few on steeper slopes -
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):
10-25% -
Number of gullies and erosion associated with gullies:
None -
Extent of wind scoured, blowouts and/or depositional areas:
None, slight wind erosion hazard -
Amount of litter movement (describe size and distance expected to travel):
Fine - 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 = 3-5 -
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
Very deep well drained clay loams, gravelly loams, or very cobbly or stony loams: moderate OM (1-3%) -
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Moderate ground cover (50-60%) and gentle to steep slopes (15-60%) moderately limit rainfall impact and overland flow -
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:
Thurber needlegrass > Bluebunch wheatgrass > shrubs > forbs > other grassesSub-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: 1200, Normal: 1000, Unfavorable: 800 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:
Western Juniper readily invades the site. Cheatgrass and Medusahead invade sites that have lost dep rooted perennial grass functional groups. -
Perennial plant reproductive capability:
All species should be capable of reproducing annually
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.