Ecological site R010XA659OR

R010XA673OR	Juniper Pumice Hills 8-11 PZ Occupying adjacent hills
R010XA675OR	Juniper Hills 8-11 PZ Occupying adjacent hills

R010XA027OR	Juniper Pumice Flat 8-10 PZ mesic rather than frigid soil temperature regime
R010XA009OR	Juniper Shrubby Pumice Flat 10-12 PZ mesic rather than frigid soil temperature regime, higher precipitation

Tree	(1) Juniperus occidentalis
Shrub	(1) Artemisia tridentata ssp. vaseyana
Herbaceous	(1) Festuca idahoensis

Landforms	(1) Tableland > Lava plain (2) Tableland > Ridge
Flooding frequency	None
Ponding frequency	None
Elevation	4500 – 4700 ft
Slope	2 – 10 %
Aspect	Aspect is not a significant factor

Frost-free period (characteristic range)	90-100 days
Freeze-free period (characteristic range)	120-140 days
Precipitation total (characteristic range)	10-10 in
Frost-free period (average)	90 days
Freeze-free period (average)	130 days
Precipitation total (average)	10 in

Parent material	(1) Volcanic ash (2) Residuum – basalt (3) Residuum – tuff
Surface texture	(1) Ashy sandy loam
Family particle size	(1) Ashy
Drainage class	Well drained
Permeability class	Moderate to moderately slow
Depth to restrictive layer	10 – 40 in
Soil depth	10 – 40 in
Surface fragment cover <=3"	0 – 45 %
Surface fragment cover >3"	0 – 45 %
Available water capacity (0-40in)	3.1 – 4.5 in
Soil reaction (1:1 water) (0-40in)	7.5 – 7.8
Subsurface fragment volume <=3" (4-40in)	0 – 20 %
Subsurface fragment volume >3" (4-40in)	5 – 35 %

Ecological dynamics

In its reference phase, this site is dominated by scattered old growth western juniper (Juniperus occidentalis) in the overstory, mountain big sagebrush (Artemisia tridentata ssp. vaseyana) in the shrub layer and Idaho fescue (Festuca idahoensis) in the herbaceous layer.

Disturbance and ecological dynamics:

While historical disturbances were most likely driven by climate, current disturbances include continued infill of western juniper, invasion of exotic annual grasses, and livestock grazing pressures. This site is considered a persistent juniper woodland, where at least some old growth juniper would be present even in the absence of altered disturbance regimes that have led to the encroachment of juniper throughout much of the Great Basin. Still, in its present state, this site is likely to have a much higher proportion of juniper than historically due to infill into these woodlands because of wildfire suppression, historic livestock grazing, and climate change (Bunting 1994). Persistent juniper woodlands often occur on sites with low productivity, coarse soils or protected rock outcrops and as such experience low fuel loading and discontinuous fuels. These conditions lead to very long fire return intervals that may range into the hundreds of years (Miller 2019). Grazing disturbance may increase the plant community composition of Thurber's needlegrass (Achnatherum thurberianum) and squirreltail (Elymus elymoides) at the expense of Idaho fescue. This site may also be susceptible to invasion by exotic annual grasses. The invasion of sagebrush communities by cheatgrass (Bromus tectorum) has been linked to disturbances (fire, abusive grazing) that have resulted in fluctuations in resources (Chambers et al. 2007).

The state and transition model below represents a partial understanding of ecological dynamics on this site as they relate to grazing pressure. Future field work will further refine and expand this model to include other disturbance dynamics such as invasion by annual grasses and encroachment of juniper.

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

1. Historic Reference

2. Altered

T1A	-	Prolonged inappropriate grazing management
R2A	-	Extended rest from grazing

State 1 submodel, plant communities

1.1. Reference Plant Community

State 2 submodel, plant communities

2.1. Altered Plant Community

State 1
Historic Reference

This is the Historic Reference state (State 1) with the absence of an altered disturbance regime.

Dominant plant species

western juniper (Juniperus occidentalis), tree
mountain big sagebrush (Artemisia tridentata ssp. vaseyana), shrub
Idaho fescue (Festuca idahoensis), grass

Community 1.1
Reference Plant Community

Dominant plant species

western juniper (Juniperus occidentalis), tree
mountain big sagebrush (Artemisia tridentata ssp. vaseyana), shrub
Idaho fescue (Festuca idahoensis), grass

Figure 7. 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	420	560
Forb	40	60	80
Shrub/Vine	40	60	80
Tree	40	60	80
Total	400	600	800

State 2
Altered

In this state (State 2), perennial grass composition has been significantly altered,

Dominant plant species

western juniper (Juniperus occidentalis), tree
mountain big sagebrush (Artemisia tridentata ssp. vaseyana), shrub
Thurber's needlegrass (Achnatherum thurberianum), grass
squirreltail (Elymus elymoides), grass

Community 2.1
Altered Plant Community

Dominant plant species

western juniper (Juniperus occidentalis), tree
mountain big sagebrush (Artemisia tridentata ssp. vaseyana), shrub
Thurber's needlegrass (Achnatherum thurberianum), grass
squirreltail (Elymus elymoides), grass

Transition T1A
State 1 to 2

Prolonged inappropriate grazing management leading to a change in perennial grass composition, marked by decreases in sensitive species such as Idaho Fescue, and an increase in disturbance adapted species such as bottlebrush squirreltail.

Restoration pathway R2A
State 2 to 1

Extended rest from grazing, allowing sensitive native grasses to increase in cover.

Context dependence.Excessive grazing leading to a loss of species diversity or reproductive output or altering abiotic conditions by significantly compacting or eroding soil, for example, will not recover by rest alone and will require additional inputs

Additional community tables

Table 6. Community 1.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)
Grass/Grasslike
1	Perennial Grasses			300–450
	Idaho fescue	FEID	Festuca idahoensis	240–300	–
	bluebunch wheatgrass	PSSPS	Pseudoroegneria spicata ssp. spicata	24–48	–
	Thurber's needlegrass	ACTH7	Achnatherum thurberianum	12–30	–
	Sandberg bluegrass	POSE	Poa secunda	6–18	–
	Indian ricegrass	ACHY	Achnatherum hymenoides	6–18	–
	squirreltail	ELEL5	Elymus elymoides	6–18	–
	prairie Junegrass	KOMA	Koeleria macrantha	6–18	–
2	Other Perennial Grasses			6–30
Forb
3	Perennial Forbs			24–48
	phlox	PHLOX	Phlox	6–12	–
	granite prickly phlox	LIPU11	Linanthus pungens	6–12	–
	buckwheat	ERIOG	Eriogonum	6–12	–
	common yarrow	ACMI2	Achillea millefolium	6–12	–
4	Other Perennial Forbs			6–30
Shrub/Vine
5	Shrubs			12–60
	mountain big sagebrush	ARTRV	Artemisia tridentata ssp. vaseyana	12–60	–
6	Other Shrubs			12–30
Tree
7	Trees			30–78
	western juniper	JUOC	Juniperus occidentalis	30–60	–
	ponderosa pine	PIPO	Pinus ponderosa	0–18	–

Table 7. Community 2.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Location 1: Lake County, OR
Township/Range/Section	T25S R20E S24
General legal description	Moonlight Butte quad in northern Lake County: T25S R20E SESW Sec 24

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	02/14/2025
Approved by
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:

Download reference sheet

Natural ResourcesConservation Service

Ecological site R010XA659OR

Juniper Pumice Plains 8-11 PZ

Last updated: 4/02/2025 Accessed: 08/06/2026

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Ecological site concept

Associated sites

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Table 1. Dominant plant species

Natural Resources
Conservation Service

Juniper Pumice Plains
8-11 PZ

Last updated: 4/02/2025
Accessed: 08/06/2026