Poa secunda - Muhlenbergia richardsonis - Carex douglasii Herbaceous Alliance
Onesided bluegrass - mat muhly - Douglas' sedge moist meadow
Onesided bluegrass - mat muhly - Douglas' sedge moist meadow
USDA Ecological Section Map
Summary Information
- Primary Life FormHerb
- Elevation900-4000 m
- State RarityS3
- Global RarityG4?
- DistributionCAN: AB, BC, MB, NB, NT, ON, QC, SK, YT. USA: AK, AZ, CA, CO, ID, ME, MI, MN, MT, ND, NE, NM, NV, OR, SD, UT, WA, WI, WY. Mexico (TJM2) (USDA Plants)
- Endemic to CaliforniaNo
- Endemic to California Floristic Province and DesertsNo
- Date Added2016/07/21
Characteristic Species
Carex douglasii, Muhlenbergia richardsonis and/or Poa secunda is dominant or co-dominant in the herbaceous layer with Achnatherum hymenoides, Achnatherum pinetorum, Astragalus whitneyi, Carex filifolia, Carex rossii, Hulsea algida, Ivesia muirii, Leptosiphon nuttallii, Linanthus pungens, Lotus purshianus, Microsteris gracilis, Monardella odoratissima, Penstemon heterodoxus or Penstemon speciosus.
Vegetation Layers
Herbs < 60 cm; cover is open to continuous.
Membership Rules
- Stands dominated by low, freshwater emergent vegetation, including Carex douglasii, Juncus articus spp. littoralis (=Juncus balticus), or Juncus mexicanus (Evens et al. 2014).
- Carex douglasii or Muhlenbergia richardsonis > 50% relative cover in stands, occuring in moist to dry, often alkaline meadows at higher elevations. (Reyes et al. 2020a).
- Poa secunda ssp. juncifolia has the highest cover in the herbaceous layer and co-occurs with a variety of species, such as Distichlis spicata and Juncus arcticus, on alkaline soils (VegCAMP 2014b).
Habitats
Drier fringes of moist meadows, valley bottoms with shallow water tables, inactive floodplains, terraces, dry basins, in swales, on upland gentle slopes and drainage bottoms. Soils are sandy to clay loams and vary in pH, though are often alkaline. The USFWS Wetland Inventory recognizes Carex douglasii as a FACU (1996 list) and FAC (2012 list) plant, Poa secunda as a FACU (1996 and 2012 list) plant, and Muhlenbergia richardsonis as a and FAC* (1996 and 2012 list) plant.
Other Habitat, Alliance and Community Groupings
MCV (1995) | Montane meadow habitat, One-sided bluegrass series, Sedge series |
NVCS (2009) | Carex douglasii herbaceous alliance, Poa secunda seasonally flooded herbaceous alliance |
Calveg | Alkaline mixed grasses and forbs, Wet grasses and forbs, Perennial grasses and forbs |
Holland | Dry montane meadow, Dry subalpine or alpine meadow, Alkali meadow |
Munz | Sagebrush scrub, Subalpine forest |
WHR | Alpine dwarf-shrub, Perennial grassland, Wet meadow |
CDFW CA Code | 41.279.00 |
National Vegetation Classification Hierarchy
Formation Class | Mesomorphic Shrub and Herb Vegetation (Shrubland and Grassland) |
Formation Subclass | Temperate and Boreal Shrubland and Grassland |
Formation | Temperate Grassland, Meadow, and Shrubland |
Division | Vancouverian and Rocky Mountain Grassland and Shrubland |
Macro Group | Western Cordilleran Montane Shrubland and Grassland |
Group | Western Cordilleran montane moist graminoid meadow |
Remarks
Carex douglasii is a non-tufted sedge with slender rhizomes and culms to 30 cm. Plants tolerate alkaline conditions. Individuals or turfs of this species may occur along compacted edges of dirt and paved roads where additional runoff may provide higher than ambient moisture.
Muhlenbergia richardsonis is a slender, perennial grass that grows in loose to dense tufts or mats, sometimes forming a sod. The stems, which may reach 2-6 dm in height, arise from the prostrate bases of old stems or from rhizomes.
Stands of M. richardsonis are turf-like and occur in more xeric settings than M. filiformis (Ratliff 1985), such as sandy and gravelly soils (Benedict 1983). Stands avoid depressions, instead occurring in snowfree areas with a long growing season (Major and Taylor 1977). Similar to M. filiformis, S. Smith (1998) found M. richardsonis in high mountain meadows with grazing disturbance, which she considered degraded stands of Carex nebrascensis, Deschampsia cespitosa, or other moist meadow sod-forming alliances.
Also, C. douglasii stands occur in similar turf-like conditions. Manning (1998) described stands on alluvial fill located along the drier fringes of meadows in valley meadow systems in northwestern Nevada. Smith (1998) suggested that stands of this type in northeastern Califonia have a history of heavy grazing and soil compaction.
Poa secunda is a native, cool-season, perennial bunchgrass that is shallowly rooted. It regenerates by tillers, by seed, and by facultatively apomictic seed. It is not shade tolerant. It produces little litter, and its small size along with its sparse litter reduces the amount of heat transferred to perennating buds in the soil (Howard 1997b).
The species occurs throughout California but the habitats of the two subspecies differ (Soreng 2007); ssp. juncifolia (including ecotypes called P. ampla, P. juncifolia, and P. nevadensis) is associated with mesic flood plains and internally drained basins and is the primary subspecies found in this alliance; whereas ssp. secunda (including ecotypes called P. canbyi, P. gracillima, P. incurva, P. sandbergii, P. scabrella) grows in scablands in ridges, plateaus, and benches on steep canyon slopes and is usually placed in drier alliances such as Aristida purpurea - Elymus elymoides - Poa secunda Alliance. We include the former Poa taxa and hybrids with P. pratensis (Hickman 1993) within this alliance.
Muhlenbergia richardsonis, Carex douglasii and Poa secunda Alliances were previously treated separately in the 2009 edition of A Manual of California Vegetation. They have been combined because they overlap in habitat and species composition, occurring in moist to drier edges of meadows (often alkaline meadows) throughout the interior western United States (NatureServe 2018).
Muhlenbergia richardsonis is a slender, perennial grass that grows in loose to dense tufts or mats, sometimes forming a sod. The stems, which may reach 2-6 dm in height, arise from the prostrate bases of old stems or from rhizomes.
Stands of M. richardsonis are turf-like and occur in more xeric settings than M. filiformis (Ratliff 1985), such as sandy and gravelly soils (Benedict 1983). Stands avoid depressions, instead occurring in snowfree areas with a long growing season (Major and Taylor 1977). Similar to M. filiformis, S. Smith (1998) found M. richardsonis in high mountain meadows with grazing disturbance, which she considered degraded stands of Carex nebrascensis, Deschampsia cespitosa, or other moist meadow sod-forming alliances.
Also, C. douglasii stands occur in similar turf-like conditions. Manning (1998) described stands on alluvial fill located along the drier fringes of meadows in valley meadow systems in northwestern Nevada. Smith (1998) suggested that stands of this type in northeastern Califonia have a history of heavy grazing and soil compaction.
Poa secunda is a native, cool-season, perennial bunchgrass that is shallowly rooted. It regenerates by tillers, by seed, and by facultatively apomictic seed. It is not shade tolerant. It produces little litter, and its small size along with its sparse litter reduces the amount of heat transferred to perennating buds in the soil (Howard 1997b).
The species occurs throughout California but the habitats of the two subspecies differ (Soreng 2007); ssp. juncifolia (including ecotypes called P. ampla, P. juncifolia, and P. nevadensis) is associated with mesic flood plains and internally drained basins and is the primary subspecies found in this alliance; whereas ssp. secunda (including ecotypes called P. canbyi, P. gracillima, P. incurva, P. sandbergii, P. scabrella) grows in scablands in ridges, plateaus, and benches on steep canyon slopes and is usually placed in drier alliances such as Aristida purpurea - Elymus elymoides - Poa secunda Alliance. We include the former Poa taxa and hybrids with P. pratensis (Hickman 1993) within this alliance.
Muhlenbergia richardsonis, Carex douglasii and Poa secunda Alliances were previously treated separately in the 2009 edition of A Manual of California Vegetation. They have been combined because they overlap in habitat and species composition, occurring in moist to drier edges of meadows (often alkaline meadows) throughout the interior western United States (NatureServe 2018).
Life History Traits of the Principal Species
Carex douglasii | Muhlenbergia richardsonis | Poa secunda | |
---|---|---|---|
Life forms | Perennial; herb | Polycarpic perennial; herb (grass); rhizomatous | Polycarpic perennial; herb |
Seed storage | null | null | Soil |
Seed longevity | null | null | Moderate |
Mode of dispersal | null | Water/hydrological, animal | Animal; gravity; wind |
Germination agents | Stratification - Winter | null | None |
Mode of sprouting | Underground structures | Underground structures (rhizomes) | Buds on large branches or trunks (basal buds, tillers) |
Survivability after fire/disturbance | Fire-hardy | Fire hardy | Fire-sensitive; no/low sprouter |
Disturbance-stimulated flowering | null | No | No |
Reproductive range | null | Life of plant | Life of plant |
Recruitment | Low | null | Low to high |
Regional variation | null | Unknown | By subspecies |
Fire Characteristics
Fluvial processes rather than fire primarily disturb the alliance, but the indicator species of this alliance have a strong ability to regenerate after disturbance.
Fire return interval | — |
Seasonality | — |
Size/extent | — |
Complexity | — |
Intensity | — |
Severity | — |
Type | — |
Regional knowledge | — |
Regional Status
The ranges of Carex douglasii and Muhlenbergia richardsonis include montane and subalpine areas throughout the state’s mountains, whereby more sampling is warranted to fully document the alliance.
- Modoc Plateau (M261Ga-p). Stands of Poa secunda ssp. juncifolia mix in a matrix with Juniperus occidentalis woodlands, Artemisia arbuscula shrublands, meadows, and seeps. Hickson et al. (2007) suggested that mesic areas contained Juncus occidentalis, Triteleia hyacinthina, and other facultative wetland species. The range of Carex douglasii includes montane and subalpine areas throughout the state’s mountains. S. Smith (1998b) described a Carex douglasii community type for a meadow on Modoc Plateau. S. Smith (1998b) described two surveys in which Muhlenbergia richardsonis was dominant in moist meadow edges and floodplains of the Modoc Plateau.
- Mono (341Dd-f, Dh-l). Stands of Poa secunda appear at meadow edges adjacent to Juncus arcticus and Artemisia cana stands throughout much of the section, including Fish Slough (VegCAMP 2014b). The range of Carex douglasii includes montane and subalpine areas with small stands occuring in the Mono area along Buckeye Creek and on flats on the northwest side of Mono Lake, as well as near Mammoth Lakes and near Crooked Creek in the White Mountains (Reyes et al. 2020a).
- Sierra Nevada (M261Ej, En, Et-u). Stands of Poa secunda in mesic meadows in the Carson Range have P. secunda ssp. juncifolia mixing with Hordeum brachyantherum, Juncus arcticus, and Poa pratensis (Manning and Padgett 1995). Major and Taylor (1977) described a Muhlenbergia richardsonis-Achnatherum pinetorum association as dry-site alpine type, which is present (Pemble 1970) in the Sierra Nevada. Ratliff (1985) recognized a Muhlenbergia richardsonis association in xeric meadows in the Sierra Nevada, and Benedict (1983) documented this same association as a drier meadow type related to Carex filifolia alliance.
- Southeastern Great Basin (341Fc). Carex douglasii stands have been sampled in the Cottonwood Mountains of Death Valley National Park (Evens et al. 2014).
- Southern California Mountains and Valleys (M262Bi). The range of Carex douglasii includes montane and subalpine areas with small stands occuring along moist arroyos in southern California, as observed in the Little San Bernardino Mountains during the reconnaissance work in Joshua Tree National Park (Keeler-Wolf et al. 2005).
- Southern Cascades (M261Da-m). S. Smith (1998b) described two surveys in which Muhlenbergia richardsonis was dominant in moist meadow edges and floodplains of the Southern Cascades.
Management Considerations
Both Carex douglasii and Muhlenbergia richardsonis tolerate grazing disturbance, and they can support a diversity of other graminoids and forbs. Ratliff (1985) and Smith (1998) noted that the abundance of these graminoids can increase at the expense of other natives in over-grazed meadows.
Poa secunda also is tolerant of disturbances, which include not only fire but also grazing, frost heaving, and invasion by non-native plants. In the Great Basin, P. secunda is one of few native grasses that can compete successfully with the invasive non-native Bromus tectorum by maintaining more positive and stable growth rates at all temperatures than B. tectorum (Monaco et al. 2005).
Bioturbation and relatively high water tables in meadows of the Great Basin facilitate the establishment and persistence of ssp. juncifolia. Saturated rooting zones during the spring and early summer prevent the establishment and persistence of Artemisia tridentata and other shrubs (Ganskopp 1986). Wright and Chambers (2002) studied meadows in a mosaic with sagebrush scrub in the Great Basin, where past grazing and road construction had lowered water tables and enabled the encroachment of shrubs into meadows. Their research showed that perennial grass cover and density increased following burning and removal of A. tridentata; thus, burning is an effective tool in restoring meadows with formerly higher water tables.
Associations
- Carex douglasii [2], [3], [5]
- Muhlenbergia richardsonis [1], [4], [5], [6]
- Muhlenbergia richardsonis - Achnatherum pinetorum [8], [12]
- Poa secunda Moist [14], [16]
- Poa secunda ssp. secunda [13]
References
- [1] Benedict, N.B. 1982
- [2] Evens, J.M.;Sikes, K.;Hastings, D.;Ratchford,J.S. 2014
- [3] Boul, R.;Keeler-Wolf, T.;Ratchford, J.;Haynes, T.;Hickson, D.;Yacoub, R.;Harbert, B.;Evens, J. 2021b
- [4] Ratliff, R.D. 1985
- [5] Smith, S. 1998b
- [6] Brown, D.E.;Lowe, C.H.;Pase, C.P. 1980
- [8] Major, J.;Taylor, D.W. 1977
- [12] Pemble, R.H. 1970
- [13] Manning, M.E.;Padgett, W.G. 1995
- [14] Weixelman, D.A.;Zamudio, D.C.;Zamudio, K.A. 1999
- [16] VegCAMP (CDFW Vegetation Classification and Mapping Program), 2014b
- Aleksoff, K.C. 1999c
- Benedict, N.B. 1983
- Hickson, D.;Boul, R.;Keeler-Wolf, T. 2008
- Manning, M. 1988
- NatureServe, 2014+
- Padgett, W.G.;Manning, M.E. 1988