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Ecological site R006XB010OR

Meadow Fan 14-26 PZ

Accessed: 11/21/2024

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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.

Associated sites

R006XB012OR	Dry Pumice Meadow 14-26 PZ Dry Pumice Meadow
R006XB013OR	Wet Pumice Meadow 14-26 PZ Wet Pumice Meadow
R006XB014OR	Meadow Swale 14-26 PZ Meadow Swale

R006XB012OR

Dry Pumice Meadow 14-26 PZ

Dry Pumice Meadow

R006XB013OR

Wet Pumice Meadow 14-26 PZ

Wet Pumice Meadow

R006XB014OR

Meadow Swale 14-26 PZ

Meadow Swale

Similar sites

R006XB011OR	Meadow Knoll 14-26 PZ Meadow Knoll

R006XB011OR

Meadow Knoll 14-26 PZ

Meadow Knoll

Table 1. Dominant plant species

Tree	Not specified
Shrub	Not specified
Herbaceous	Not specified

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Physiographic features

Table 2. Representative physiographic features

Landforms	(1) Basin floor (2) Alluvial fan (3) Terrace
Flooding duration	Brief (2 to 7 days)
Flooding frequency	Rare
Ponding duration	Brief (2 to 7 days) to long (7 to 30 days)
Ponding frequency	Occasional
Elevation	4,000 – 6,000 ft
Slope	3%
Ponding depth	1 – 2 in
Water table depth	48 – 60 in
Aspect	Aspect is not a significant factor

Climatic features

This site is characterized by relatively short, hot summers and cold, snowy winters. The site receives approximately 20 inches of precipitation per year, the bulk of which is snowfall. There are frequent thunderstorms in the summer months. There may be ground fogs in the mornings during the growing season which affect stomatal gas exchange and photosynthetic activity.

Table 3. Representative climatic features

Frost-free period (average)	20 days
Freeze-free period (average)	49 days
Precipitation total (average)	25 in

Bar

Line

Figure 1. Monthly precipitation range

Bar

Line

Figure 2. Monthly average minimum and maximum temperature

Soil features

The soil has a well-developed argilic horizon with small amounts of glassy pumice (pre-Mazama). The soil is relatively old; Mazama pumice is eroded off the surface of the soil. There is a semi-impermeable layer in the soil at about 20 inches (it almost classifies as a duranode) that turns most roots away from the subsoil (allowing the Low Sagebrush to grow on the site). The apparent water table can penetrate the layer and saturate the surface for short periods. The water table comes to within 24 inches of the surface early in the growing season.

Table 4. Representative soil features

Surface texture	(1) Loam
Family particle size	(1) Loamy
Drainage class	Moderately well drained
Permeability class	Moderate
Soil depth	36 – 50 in
Surface fragment cover <=3"	Not specified
Surface fragment cover >3"	Not specified
Available water capacity (0-40in)	5 – 6 in
Calcium carbonate equivalent (0-40in)	2%
Electrical conductivity (0-40in)	2 mmhos/cm
Sodium adsorption ratio (0-40in)	1
Soil reaction (1:1 water) (0-40in)	2
Subsurface fragment volume <=3" (Depth not specified)	Not specified
Subsurface fragment volume >3" (Depth not specified)	Not specified

Ecological dynamics

The sites are on remnant terraces and alluvial fans and are adjacent to or are islands within wetland sites. Elevations may differ by only 2 or 3 feet from adjacent wet sites. The sites are particularly dry in the summer; however, there is an apparent seasonal water table that has a marked influence on plant growth early in the growing season. All states have relatively thick clay layers in the subsoil and small amounts of pre-Mazama pumice. The interpretative plant community for this site is the Historic Climax Plant Community (HCPC).

State and transition model

Custom diagram

Standard diagram

Figure 3. Meadow Fan 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

State 1
State B, ARCA13/POSE3-CAMI7

Community 1.1
State B, ARCA13/POSE3-CAMI7

Dominated by Silver Sagebrush Nevada bluegrass and Small-wing Sedge. Sites in this state receive excess water and may have impermeable layer in the subsoil. Ponding duration is increased.

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	700	900	1100
Shrub/Vine	150	175	200
Forb	50	75	100
Total	900	1150	1400

Figure 5. Plant community growth curve (percent production by month). OR1852, B6 Meadow Fan B. State B: Disturbance/Dry (ARCA13/POSE3-CAMI7) .

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	10	25	30	20	5	0	5	5	0	0

State 2
HCPC, ARAR8-ARCA13/FEID/CAFI

Community 2.1
HCPC, ARAR8-ARCA13/FEID/CAFI

Dominated by Low sagebrush, Silver Sagebrush, Idaho Fescue, and Threadleaf Sedge. A weak cemented layer allow the Low sagebrush to thrive.

Figure 6. 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	300	425	550
Shrub/Vine	175	213	250
Forb	100	130	160
Total	575	768	960

Figure 7. Plant community growth curve (percent production by month). OR1851, B6 Meadow Fan RPC. State A: HCPC-ARAR8-ARCA13/FEID-CAFI B6 Meadow Fan RPC.

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	5	15	35	30	10	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				350–560
	Sandberg bluegrass	POSE	Poa secunda	280–420	–
	smallwing sedge	CAMI7	Carex microptera	210–350	–
	prairie Junegrass	KOMA	Koeleria macrantha	70–140	–
	squirreltail	ELEL5	Elymus elymoides	35–70	–
	slender wheatgrass	ELTRT	Elymus trachycaulus ssp. trachycaulus	35–70	–
2				35–140
	prairie Junegrass	KOMA	Koeleria macrantha	140–210	–
	mat muhly	MURI	Muhlenbergia richardsonis	35–70	–
	Kentucky bluegrass	POPR	Poa pratensis	35–70	–
	Nebraska sedge	CANE2	Carex nebrascensis	35–70	–
	squirreltail	ELEL5	Elymus elymoides	35–70	–
	slender wheatgrass	ELTRT	Elymus trachycaulus ssp. trachycaulus	35–70	–
3				245–420
	smallwing sedge	CAMI7	Carex microptera	210–350	–
	Nebraska sedge	CANE2	Carex nebrascensis	35–70	–
4				34–70
Forb
3				50–100
	common yarrow	ACMI2	Achillea millefolium	28–42	–
	pussytoes	ANTEN	Antennaria	28–42	–
4				1–42
	buckwheat	ERIOG	Eriogonum	1–28	–
	old man's whiskers	GETR	Geum triflorum	1–28	–
	cinquefoil	POTEN	Potentilla	1–28	–
5				56–84
	common yarrow	ACMI2	Achillea millefolium	28–42	–
	pussytoes	ANTEN	Antennaria	28–42	–
6				1–42
	buckwheat	ERIOG	Eriogonum	1–28	–
	old man's whiskers	GETR	Geum triflorum	1–28	–
	cinquefoil	POTEN	Potentilla	1–28	–
Shrub/Vine
5				150–200
	silver sagebrush	ARCA13	Artemisia cana	140–210	–
	yellow rabbitbrush	CHVI8	Chrysothamnus viscidiflorus	14–28	–
7				150–200
	silver sagebrush	ARCA13	Artemisia cana	140–210	–
	yellow rabbitbrush	CHVI8	Chrysothamnus viscidiflorus	14–28	–

Table 8. Community 2.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production (lb/acre)	Foliar cover (%)
Grass/Grasslike
1				255–450
	Idaho fescue	FEID	Festuca idahoensis	225–360	–
	Sandberg bluegrass	POSE	Poa secunda	45–90	–
	threadleaf sedge	CAFI	Carex filifolia	45–90	–
	squirreltail	ELEL5	Elymus elymoides	15–45	–
2				30–90
	squirreltail	ELEL5	Elymus elymoides	15–45	–
	prairie Junegrass	KOMA	Koeleria macrantha	15–45	–
	Kentucky bluegrass	POPR	Poa pratensis	15–45	–
	Sandberg bluegrass	POSE	Poa secunda	15–45	–
3				45–90
	threadleaf sedge	CAFI	Carex filifolia	45–90	–
4				15–45
Forb
3				100–160
	old man's whiskers	GETR	Geum triflorum	45–72	–
	pussytoes	ANTEN	Antennaria	27–45	–
4				3–63
	common yarrow	ACMI2	Achillea millefolium	3–27	–
	buckwheat	ERIOG	Eriogonum	3–27	–
	cinquefoil	POTEN	Potentilla	3–27	–
6				3–63
	common yarrow	ACMI2	Achillea millefolium	3–27	–
	buckwheat	ERIOG	Eriogonum	3–27	–
	cinquefoil	POTEN	Potentilla	3–27	–
Shrub/Vine
5				175–250
	little sagebrush	ARAR8	Artemisia arbuscula	180–225	–
	silver sagebrush	ARCA13	Artemisia cana	27–45	–
	yellow rabbitbrush	CHVI8	Chrysothamnus viscidiflorus	9–18	–
7				175–250
	little sagebrush	ARAR8	Artemisia arbuscula	180–225	–
	silver sagebrush	ARCA13	Artemisia cana	27–45	–
	yellow rabbitbrush	CHVI8	Chrysothamnus viscidiflorus	9–18	–

Interpretations

Animal community

Several grazing animals seasonally use the site. Mule deer, elk, and antelope use the site for both grazing and resting. Antelope are perhaps the most frequent animals on the site. Mule deer and elk use the site int he late winter and early spring. The position of the site makes it attractive to grazing animals when the adjacent sites are wet; it is often used as a resting and ruminating area. The site is marginal for nesting birds but may be seasonally used by waterfowl which nest in the adjacent meadow and marsh sites.

Hydrological functions

The site has a high potential in low seral condition to produce significant run-off to receiving water. IN some years, the site may be flooded with water backed up in the adjacent wetter sites. Adjacent wetter and lower sites surrounding the site provide extra ground water that may move laterally through the Meadow Fan site.

Recreational uses

There is little recreational use on this site other than big game hunting and bird watching.

Other information

Due to the relatively dry nature of this site, there is a possibility that American Indians used this site for temporary, seasonal hunting camps. Survey the area carefully before recommending ground disturbing practices. The aid of an archaeologist maybe be needed.
Grazing- The site is frequently used for grazing by domestic livestock and wildlife (mule deer, elk, and antelope). There are several species that are preferred that are available for most of the growing season. The site can be havily used because the slightly higher elevation of this site makes it drier than adjacent meadow sites and therefore more attractive for resting, ruminating, and grazing.
Wildlife- There is little use by wildlife other than by grazing animals (see above). The elevated position of the site and its proximity to important wetter meadow sites makes it an important part of the entire meadow/marsh ecosystem.

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
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:

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