Natural Resources
Conservation Service
Ecological site R006XB012OR
Dry Pumice Meadow 14-26 PZ
Accessed: 12/03/2024
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.
Associated sites
| R006XB011OR |
Meadow Knoll 14-26 PZ The site is situated at the edges of wetter, marshy areas and is adjacent to Ponderosa and Lodgepole pine forestlands (Pine Fescue sites are most common). It may also be associated with Meadow Knoll sites on remnant fans and terraces (from pre-Mazama materials). Complexes of Dry Pumice Meadow, Wet Pumice Meadow, and Meadow Swale are common, often with only micro-relief between sites. |
|---|
Similar sites
| R006XB013OR |
Wet Pumice Meadow 14-26 PZ There are similar sites on similar positions (Wet Pumice Meadow) but none will have the predominance of Cusick's Bluegrass exhibited by Dry Pumice Meadow. |
|---|
Table 1. Dominant plant species
| Tree |
Not specified |
|---|---|
| Shrub |
Not specified |
| Herbaceous |
Not specified |
Physiographic features
Table 2. Representative physiographic features
| Landforms |
(1)
Alluvial fan
|
|---|---|
| Flooding frequency | None |
| Ponding duration | Long (7 to 30 days) to very long (more than 30 days) |
| Ponding frequency | Frequent |
| Elevation | 4,000 – 6,000 ft |
| Slope | 1% |
| Ponding depth | 1 – 3 in |
| Water table depth | 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 thundrstorms 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 |
Figure 1. Monthly precipitation range
Figure 2. Monthly average minimum and maximum temperature
Influencing water features
Soil features
Soils for this site typically have a thin organic layer over loams, layers of coarse pumice over heavy clay loams. There is an apparent water table present for most of the year. These relatively young soils have been deposited over older, remnant fans and terraces. Variations and intergrades of soil characteristics are common.
Table 4. Representative soil features
| Surface texture |
(1) Loam |
|---|---|
| Family particle size |
(1) Loamy |
| Drainage class | Somewhat poorly drained |
| Permeability class | Slow |
| Soil depth | 38 – 60 in |
| Surface fragment cover <=3" | 2% |
| Surface fragment cover >3" | 2% |
| Available water capacity (0-40in) |
4.5 – 5.5 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) |
2% |
| Subsurface fragment volume >3" (Depth not specified) |
2% |
Ecological dynamics
This site occurs on alluvial fans leading to deeper and lower marshy sites. It is intermediate between these wetter sites and adjacent Ponderosa Pine forest sites. The water table is apparently below the effective rooting depth for the grass species present for a major portion of the growing season (depth to water table during the period of rapid growth appears to have a significant influence on the plant community). Dry Pumice Meadows are the driest types of grasslands within larger complexes of wetlands sites. The interpretative plant community for this site is the Historic Climax Plant Community (HCPC).
State and transition model
Figure 3. Dry Pumice Meadow 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: POCU3-MUSQ2
Community 1.1
HCPC: POCU3-MUSQ2
This site is a widely spread intergrade between dryer pine forestland and wetter marshlands. It is dominated by Cusicks Bluegrass and Matt Muhly with a moderate component of perennial forbs (particularly Antennaria sp.).
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 | 2600 | 3000 | 3300 |
| Total | 2600 | 3000 | 3300 |
Figure 5. Plant community growth curve (percent production by month). OR1871, B6 Dry Pumice Meadow RPC. State A: RPC (POCU3-MUSQ2) B6 Dry Pumice Meadow 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 | 10 | 30 | 35 | 10 | 0 | 5 | 5 | 0 | 0 |
State 2
State B: POSE3-JUBA-CAMI7
Community 2.1
State B: POSE3-JUBA-CAMI7
This site is characterized on areas where excess grazing has removed the Cusicks Bluegrass and hydrologic modification has added sub-surface water during the growing season. the site is dominated by Nevada Bluegrass, Baltic Rush, and Small-winged Sedge.
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 | 3000 | 3400 | 3700 |
| Total | 3000 | 3400 | 3700 |
Figure 7. Plant community growth curve (percent production by month). OR1872, B6 Dry Pumice Meadow B. State B: Disturbance/Moist (P0SE3-JUBA-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 | 5 | 15 | 25 | 25 | 20 | 0 | 5 | 5 | 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 | 1150–1800 | |||||
| Cusick's bluegrass | POCU3 | Poa cusickii | 750–1200 | – | ||
| Sandberg bluegrass | POSE | Poa secunda | 300–450 | – | ||
| slender wheatgrass | ELTRT | Elymus trachycaulus ssp. trachycaulus | 100–150 | – | ||
| 2 | 410–690 | |||||
| prairie Junegrass | KOMA | Koeleria macrantha | 150–240 | – | ||
| mat muhly | MURI | Muhlenbergia richardsonis | 60–150 | – | ||
| Kentucky bluegrass | POPR | Poa pratensis | 100–150 | – | ||
| meadow barley | HOBR2 | Hordeum brachyantherum | 100–150 | – | ||
| 3 | 280–450 | |||||
| smallwing sedge | CAMI7 | Carex microptera | 100–150 | – | ||
| Nebraska sedge | CANE2 | Carex nebrascensis | 90–150 | – | ||
| clustered field sedge | CAPR5 | Carex praegracilis | 90–150 | – | ||
| 4 | 150–240 | |||||
|
Forb
|
||||||
| 5 | 60–300 | |||||
| pussytoes | ANTEN | Antennaria | 30–150 | – | ||
| cinquefoil | POTEN | Potentilla | 30–150 | – | ||
| 6 | 5–240 | |||||
| common yarrow | ACMI2 | Achillea millefolium | 90–240 | – | ||
| aster | ASTER | Aster | 90–240 | – | ||
| Virginia strawberry | FRVI | Fragaria virginiana | 90–240 | – | ||
| Rainier pleated gentian | GECA | Gentiana calycosa | 90–240 | – | ||
| dwarf hesperochiron | HEPU6 | Hesperochiron pumilus | 90–240 | – | ||
| buttercup | RANUN | Ranunculus | 90–240 | – | ||
Table 8. Community 2.1 plant community composition
| Group | Common name | Symbol | Scientific name | Annual production (lb/acre) | Foliar cover (%) | |
|---|---|---|---|---|---|---|
|
Grass/Grasslike
|
||||||
| 1 | 853–1290 | |||||
| Sandberg bluegrass | POSE | Poa secunda | 850–1190 | – | ||
| slender wheatgrass | ELTRT | Elymus trachycaulus ssp. trachycaulus | 3–100 | – | ||
| 2 | 109–575 | |||||
| Kentucky bluegrass | POPR | Poa pratensis | 100–275 | – | ||
| onespike danthonia | DAUN | Danthonia unispicata | 3–100 | – | ||
| meadow barley | HOBR2 | Hordeum brachyantherum | 3–100 | – | ||
| prairie Junegrass | KOMA | Koeleria macrantha | 3–100 | – | ||
| 3 | 510–1025 | |||||
| Nebraska sedge | CANE2 | Carex nebrascensis | 170–410 | – | ||
| smallwing sedge | CAMI7 | Carex microptera | 240–340 | – | ||
| clustered field sedge | CAPR5 | Carex praegracilis | 100–275 | – | ||
| 4 | 170–510 | |||||
|
Forb
|
||||||
| 5 | 440–920 | |||||
| pussytoes | ANTEN | Antennaria | 170–340 | – | ||
| cinquefoil | POTEN | Potentilla | 170–340 | – | ||
| buttercup | RANUN | Ranunculus | 100–240 | – | ||
| 6 | 10–270 | |||||
| common yarrow | ACMI2 | Achillea millefolium | 10–70 | – | ||
| aster | ASTER | Aster | 10–70 | – | ||
| Rainier pleated gentian | GECA | Gentiana calycosa | 10–70 | – | ||
| roundfruit hedgehyssop | GRVI | Gratiola virginiana | 10–70 | – | ||
| bigleaf lupine | LUPO2 | Lupinus polyphyllus | 10–70 | – | ||
Interpretations
Animal community
The site is seasonally utilized by several grazing animals. 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 in the late winter and early spring. The proximity of pine forest (for cover and shelter) makes these sites desirable for grazing by elk and mule deer. 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 waters. In some years, the site may be flooded with water backed up in the adjacent wetter sites. The site is important in its ability to store ground water in the lower portion of the soil profile and release it slowly. The high amounts of pumice in the soil allows lateral movement of large quantities of water throughout the meadow ecosystem.
Recreational uses
There is little recreational use on this site other than big game hunting and bird watching.
Wood products
None
Other products
None
Other information
There is little use by wildlife other than by grazing animals (see below). 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. The site may have a notable number of ant mounds which are high enough to protect the colony when the water table rises. The significance of the mounds and the function of the ants in this ecosystem is not fully understood. The mounds are found on other, drier sites, but not the number of distribution in the Dry Pumice Meadow Site.
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 heavily used because the slightly higher elevation of this site makes it drier than adjacent meadow sites and therefore more attractive for resting, reminating, and grazing.
Supporting information
Contributors
Jeffrey P. Repp
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:
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.