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This description covers characteristics that may be relevant to fire ecology and is not meant for identification. Keys for identification are available (e.g., [5,16,23,25,26,31,32,44,45,72]).
Spiked muhly has slender, erect to suberect culms that reach 10 to 47 inches (25-120 cm) tall [5,16,22,25,26,31,34,43,44,58] and 0.8 to 2.5 mm thick [5]. Culms have a few erect branches at the base [31,32,43,44,64] or, rarely, are branched above the base [5,16,18,22,25,34,43,72]. The internodes are dull and minutely puberulent [5,22,26,31,43,44,58] or glabrous [58]. Spiked muhly leaf blades are flat [5,16,23,25,31,34,43] or loosely involute [26], ascending [31], 1 to 6 inches (2-15 cm) long, and 1.5 to 6 mm wide [5,16,22,23,25,26,31,43]. The inflorescence is a narrow, compact panicle, 0.6 to 6 inches (1.5-15 cm) long [5,22,25,26,31,43,44,58] and 3 to 18 mm wide [5,22,43,58], with spikelets 3 to 8 mm long [5,22,26,31,44,58]. Spiked muhly fruits are caryopses, 1 to 1.6 mm [5].
Spiked muhly is strongly rhizomatous [5,22,25,26,34,44]. Rhizomes are described as either slender [23] or stout [43], scaly [16,23,31,43], and abundant [55]. One author indicated that spiked muhly rhizomes were 1.5 to 2 mm in diameter [58]. In fens in Ontario, spiked muhly rhizomes were typically located in the top 1.2 to 1.6 inches (3-4 cm) of the moss layer [40].
Spiked muhly differs morphologically from green muhly in internode pubescence [33,43,55], ligule length [33,55], anther length, lemma pubescence [55], and location of branching [33]. Because some authors cited in this review may have lumped or misidentified these 2 species, some information in this review may pertain to green muhly.
According to the Plants database, spiked muhly occurred in the following states and provinces as of 2011 [71]:
Spiked muhly is the most northerly species in the Muhlenbergia subgenus. It usually occurs in small, isolated colonies in moist habitats and is most common in the southern portion of the glaciated region of southern Canada and the northeastern United States [49,55], ranging south in a scattered and disjunct pattern to North Carolina [73]. It also occurs in isolated locations in the Southern Appalachians and Northern Great Plains. These populations may represent relict colonies of a wider Pleistocene distribution [49,55]. Spiked muhly grows sporadically throughout western North America but is not known from Mexico [5].
Because some authors have lumped green muhly with spiked muhly (e.g., [32,33]), a distribution that reflects the combined distribution of both species is sometimes given (e.g., [33,74]). Hitchcock and others [32,33] suggest that spiked muhly is more common in the Pacific Northwest, and green muhly is more common from the Rocky Mountains eastward. Pohl [55] indicates that green muhly is adapted to much drier sites and regions than spiked muhly. According to Larson [43], spiked muhly is restricted to permanently wet habitats, whereas green muhly occurs in a variety of upland and lowland habitats. Because some authors cited in this review may have lumped or misidentified these 2 species, some information in this review may pertain to green muhly.
Fire management considerations likely vary among the plant communities in which spiked muhly occurs. However, insufficient information is available to make recommendations for managing spiked muhly with or without fire.
One study, in aspen parkland in east-central Alberta, suggests that seed production in spiked muhly may increase after fire [1], and one publication [51] recommends using prescribed fire to manage a plant community in which spiked muhly occurs: the pitch pine-white oak/prairie dropseed-big bluestem woodland in the Nantahala and Pisgah National Forests of North Carolina (see FIRE REGIMES). It is suggested that periodic fire may help maintain the graminoid-dominated understory, of which spiked muhly is a component [51]. Conversely, data from an Illinois fen [7] suggest that frequent fire may reduce abundance of spiked muhly in undisturbed fen communities.
It is unclear from the available literature (as of 2011) what type of fire regime spiked muhly is best adapted to. However, as a rhizomatous plant that typically occurs in open plant communities and microsites, it would likely tolerate relatively short fire-return intervals in some plant communities. For example, spiked muhly is a characteristic species in alvar communities in the Great Lakes region [10], where fires were common in presettlement and early settlement times [11].
Spiked muhly is among several species that occur in the rare ultramafic outcrop barren community and the pitch pine-white oak/prairie dropseed-big bluestem woodland in North Carolina; both of these communities seem to be shaped by periodic fires. The presettlement fire frequency of these communities is not known; however, the dry, grassy vegetation is flammable and the harsh environment may allow only slow recovery of woody plants after fire. The barren community may be more affected by fire than surrounding communities on more favorable sites [63]. The presettlement fire frequency for the pitch pine-white oak/prairie dropseed-big bluestem woodland is also unknown. However, the dry grassy vegetation is flammable, and it is suggested that periodic fire would help maintain the graminoid-dominated understory. In the absence of occasional fire, shrub density increases and herbaceous cover decreases. The overstory composition and structure are likely maintained, at least in part, by the harsh soil conditions, and recovery of woody species following a fire may be slow [51].
Spiked muhly occurs in boreal and sub-boreal graminoid fens, which are sometimes subject to severe fire. However, in wet peatlands the peat layer is seldom eliminated, and the original species assemblages may return within a decade (reveiw by [40]). While fire is an important modifier of boreal ecology in general (see FEIS review on ribbed bog moss for a summary of boreal peatland FIRE REGIMES), Kubien and Sage [40] suggest that it is unlikely that fire could occur frequently enough to have a prominent role in promoting the occurrence of spiked muhly in boreal fens. The effects of frequent fire on spiked muhly in an Illinois fen community were equivocal [7], and its response might depend on the history of disturbances at a given site.
See the Fire Regime Table for further information on FIRE REGIMES of vegetation communities in which spiked muhly may occur. Find further fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find FIRE REGIMES".
No information was available (as of 2011) regarding the importance or use of spiked muhly by wildlife and livestock. Spiked muhly occurs in some areas on sites disturbed by wildlife and livestock (see Successional Status), suggesting that it may be less palatable than associated species to grazing animals in these communities.
Spiked muhly was found in 3 of 25 Kirtland's warbler nests examined in jack pine (Pinus banksiana) savannas and burns in the Lower Peninsula of Michigan [67].
Palatability and nutritional value: No information is available on these topics.
Cover value: No information is available on this topic.
General site characteristics: Spiked muhly is the most hydrophilic species in the subgenus Muhlenbergia [55], and it usually occurs on moist to wet, open ground [18,21,31,52] on sites that are at least seasonally flooded (e.g., [29,61,70]). Typical habitats include open marshes, gravelly shores, peaty meadows, moist ditches, sphagnum (Sphagnum) bogs, alkaline fens, swamps, shorelines, streambanks, hot springs, and wet deciduous woods [5,22,45,49,55,64,65,76]. Soils may be Histosols (e.g., [29]), or have high organic matter content in the surface layers (e.g., [21,29,61,69]). Sites where spiked muhly occurs are often calcareous (e.g., [61,69]) and/or have circumneutral pH (e.g., [21,29,69]).
Spiked muhly sometimes grows on rock outcrops, where soils tend to be shallow (e.g., [54,61,70]) and seepage provides extra water. See the section on plant communities in the Southern Appalachians for more detailed examples.
Spiked muhly occasionally occurs in relatively dry sites such as upland forests [49,55], dry, sandy openings in the middle Ottawa Valley [8], aspen (Populus spp.) parkland in Alberta [1], and gravelly or rocky slopes [5].
Spiked muhly is a C4 plant. These tend to be rare in cool climates; however, spiked muhly often occurs in boreal fens and can occur at latitudes above 60° N (e.g., [40]). One might expect spiked muhly to occur in relatively warm, dry microsites in these fens, where C4 photosynthesis would be favored. However, a survey of 19 spiked muhly populations in boreal and sub-boreal fens across northern Ontario revealed that spiked muhly was restricted to wet microsites where woody plant cover was more sparse (P<0.0001), sedge (Cyperaceae) cover was greater (P≤0.0044), and dead moss depth more shallow (P≤0.0095) than on sites without spiked muhly. Woody plants covered less than 20% of the ground area in plots where spiked muhly was present but more than 50% in plots where it was absent. Spiked muhly was largely restricted to wet hollows, and its stem density decreased as the distance from standing water increased. In contrast to wet hollows, drier hummocks were dominated by woody plants, which were probably limited in hollows due to flooding. Shade from woody plants may have helped exclude spiked muhly from hummocks [40].
Spiked muhly occurs at elevations ranging from 98 to 7,550 feet (30-2,300 m) [5]. Elevations reported by area are as follows:
Area Elevation Aroostook River, Maine 460 feet [60] Riparian and wetland sites in Montana 2,200-8,320 feet [29] Nantahala and Pisgah National Forests, North Carolina 3,330 feet [51] Western North Carolina 4,100-5,600 feet [77] Uinta Mountains, Utah 7,360 feet [24] Shoshone National Forest, Wyoming 4,700-6,600 feet [34]Spiked muhly typically occurs in relatively undisturbed sites (e.g., [6,8,38,44,48,75]), but it is also noted in communities disturbed by fire (e.g., [13]) or grazing animals (e.g., [28,29,70]). See Successional Status for details. It has also been reported along roadsides and railways (e.g., [45,49,55]), and in "waste places" [45].
Plant communities: Spiked muhly typically occurs in herbaceous-dominated communities in wetlands and riparian areas. It is characteristic of open fens and alvar grasslands, where it typically has relatively low cover and is rarely a community dominant. Exceptions include the wiregrass sedge-tufted bulrush-needle beaksedge/bog rosemary (Carex lasiocarpa-Trichophorum cespitosum-Rhynchospora capillacea/Andromeda polifolia var. glaucophylla) herbaceous vegetation type that occurs in northern Minnesota, Manitoba, and northern Ontario, and Iowa fens where spiked muhly may be a community dominant. The vegetation is dominated by an open graminoid layer of sedge and rush species including spiked muhly [69]. Spiked muhly was a dominant species in 2 plant communities described from Iowa fens. One was the most commonly encoutered Iowa fen mat vegetation, which was dominated by purplestem aster (Symphyotrichum puniceum var. puniceum), American water horehound (Lycopus americanus), spiked muhly, northern bog violet (Viola nephrophylla), and fourflower yellow loosestrife (Lysimachia quadriflora). The other was dominated by species requiring both relatively high moisture levels and calcareous conditions such as spiked muhly, fen grass of Parnassus (Parnassia glauca), elliptic spikerush (Eleocharis elliptica), needle beaksedge, and Ontario lobelia (Lobelia kalmii) [52].
Plant communities and site characteristics by region:
Great Lakes: In the Great Lakes region, spiked muhly is most commonly described in fens [6,9,15,21,40,52,61], alvars [10,11,61], bogs [19,48], and wet prairies [38,39]. In Michigan, for example, spiked muhly is widespread in marshes, swamps, bogs (open mats and older tamarack (Larix laricina)), boggy meadows, calcareous shores, "springy places", and moist clearings in woods [72].
Spiked muhly is a common, widespread, and sometimes prevalent species in fens in Minnesota [21], Iowa [52], Wisconsin [9], Illinois [6,50], Ohio [15], New York [61], and Ontario [40]. In a study of the Lost River peatland in northern Minnesota, spiked muhly was referred to as an indicator of extremely rich fen. It occurred in spring-fen channels along with other rich-fen indicators including alpine bulrush (Trichophorum alpinum), smooth sawgrass (Cladium mariscoides), and marsh grass of Parnassus (P. palustris). Dominants included tufted bulrush (T. cespitosum), mud sedge (Carex limosa), smooth sawgrass, and woollyfruit sedge (C. lasiocarpa) [21]. In an ordination of 31 fens in Iowa, spiked muhly was present in all compositional groups and was dominant in 2: Iowa fen mats, and a group dominated by species requiring both relatively high moisture and calcareous conditions [52]. In the Bluff Spring Fen in northeastern Illinois, spiked muhly is most frequent in marl flats (44% frequency), followed by calcareous seep (27% frequency) and graminoid fen (9% frequency) communities [6]. At Betsch Fen, a remnant periglacial fen in south-central Ohio, spiked muhly occurred in the sedge meadow but not in the open marl, shrub meadow, or forest communities. The sedge meadow community was dominated by tussock sedge (C. stricta) and patches of other sedges (Carex spp.) [15]. Spiked muhly is a characteristic herb in rich sloping fen and rich graminoid fen communities in New York [61]. The structure of the rich sloping fen community is variable; usually there are scattered trees and shrubs and a nearly continuous groundlayer of herbs and bryophytes, and species diversity is very high. Rich graminoid fens are dominated by sedges, although grasses and rushes may be common [61]. Spiked muhly is often associated with bluejoint reedgrass (Calamagrostis canadensis) in Ontario fens [40].
Spiked muhly is a characteristic species in alvar communities in the Great Lakes region [10] and considered more frequent on successional alvar burns than in any other natural habitat in the Ottawa-Carleton region. In the Burnt Lands Alvar on an extensive limestone plateau in eastern Ontario, spiked muhly occurred at all stages of succession [12,13], but was most frequent in an area burned 37 years prior to sampling (see Successional Status for details). The sampled area was dominated by graminoids and shrubs but was forested before the fire and dominated by white spruce (Picea glauca), quaking aspen (Populus tremuloides), eastern white pine (Pinus strobus), northern whitecedar (Thuja occidentalis), and balsam fir (Abies balsamea) [11]. In New York, spiked muhly is a characteristic species in alvar grassland communities that may include 2 or 3 species assemblages that seem to be correlated with soil moisture and soil depth [61].
Spiked muhly has been noted in bog communities in Illinois [19] and Wisconsin [48]. It occurred in a well developed, shallow, sphagnum bog in northern Illinois [19]. Spiked muhly occurred in Cedarburg Bog with 1.2% average frequency and 2.3% average cover in 1991 and 4.2% frequency and 4.9% average cover in 2006. Cedarburg Bog is one of the largest intact, relatively undisturbed wetlands in southeastern Wisconsin, and the southernmost example of string bogs in North America, in which "strings" of stunted trees and ericaceous shrubs alternate with swales dominated by low-growing herbaceous plants, especially sedges. Carnivorous plants were common in the wetland, indicating low nutrient availability. Sphagunum was widespread. Tamarack and northern whitecedar covered most of the wetland [48].
Spiked muhly occurred in a large, relatively undisturbed wet prairie dominated by sedges (Carex spp.) and goldenrods (Solidago spp.) at Indian Bowl Wet Prairie in southern Michigan. This community is unique in Michigan due to its size and the presence of rare plant species [38,39].
Northeast: Little information was available regarding plant communities supporting spiked muhly in the Northeast, but it appears to occur in habitats similar to those in the Great Lakes region. Spiked muhly occurs in a northern bayberry-shrubby-cinquefoil/dioecious sedge-yellow sedge (Myrica pensylvanica-Dasiphora fruticosa subsp. floribunda/Carex sterilis-C. flava) marl fen association, which is restricted to New Jersey, Pennsylvania, and perhaps New York [54]. Spiked muhly was observed in this association at a single location at Delaware Water Gap National Recreation Area, Pennsylvania [53]. This association is characterized by herbaceous vegetation (usually about 40% herbaceous cover) and a typically sparse shrub layer (less than 25% cover) [54]. In Maine, spiked muhly occurred among prairie vegetation dominated by mat muhly (Muhlenbergia richardsonis) along a series of flood-scoured bedrock ledges along the Aroostook River [60].
Northern Great Plains: Spiked muhly is uncommon in the Northern Great Plains and is generally restricted to permanently wet habitats such as wet meadows, springs, fens, and boggy areas, from northern Nebraska and Wyoming to North Dakota [4,25,43], Alberta, and Saskatchewan [4]. Spiked muhly occurred in forests and meadows near the southern limit of its North American distribution at the Niobrara Valley Preserve in the sandhills of north-central Nebraska [30]. In the Saskatchewan prairie ecozone, spiked muhly occurred in the water birch (Betula occidentalis) community type on sites that were disturbed by livestock or wildlife. This is an incidental type at low elevations in southern Saskatchewan. Stands occupy alluvial terraces, streambanks, floodplains, moist areas around springs and seeps located along valley toe slopes, and pockets around seeps hanging on steep valley walls [70].
Southern Appalachians: Spiked muhly is very rare to infrequent in the Southern Appalachians [58,73,78], occurring in widely separated places in the mountains of Virginia and North Carolina [20,23,47,73]. Habitats include bogs [23,58], swamps [78], shores, meadows [23], fens [73], and seeps [57,73].
Some of the habitats supporting spiked muhly in the Southern Appalachians are unique in their geology, hydrology, and plant community compositions, such as high-elevation seeps over mafic (amphibolite) or ultramafic (olivine) rocks [57,73]. Amphibolite produces unusually rich soils with high elemental concentrations of calcium, magnesium, aluminum, and iron, typically circumneutral in pH, and supporting high levels of diversity and an abundance of rare plants. At Mount Jefferson State Natural Area, North Carolina, spiked muhly occurred in a small seep at the base of the high elevation mafic glade community, a critically imperiled community occurring on "gently sloping, high elevation amphibolite outcrops with patchy, shallow soils supporting a mosaic of grass and shrub vegetation alternating with bare rock". The community is dominated primarily by an array of forb and graminoid taxa that are confined to scattered soil pockets. Characteristic species include little bluestem, hoary frostweed (Crocanthemum bicknellii), flaxleaf whitetop aster (Ionactis linariifolius), greater tickseed (Coreopsis major), poverty oatgrass (Danthonia spicata), and lichens (Cladonia spp. and Cladina spp.) [57]. The montane mafic cliff community occurs on very steep to vertical, rocky slopes of mafic or basic igneous or metamorphic rocks in North Carolina. Soils are a heterogeneous mosaic ranging from bare rock to accumulations of organic or mineral matter in pockets and crevices, to thin and rocky soils. Dry microsites may be intermixed with wet seepage areas, such that xerophytic and mesophytic species occur in close proximity. Presence of base-loving flora distinguishes mafic cliffs from acidic cliffs [63].
Spiked muhly is a characteristic species of the pitch pine-oak (white oak (Quercus alba), post oak (Q. stellata) forest alliance in shallow, rocky soils over ultramafic rocks in the Southern Blue Ridge Mountains. This alliance includes open woodland vegetation over a dense herbaceous stratum with little shrub cover. The herbaceous stratum is dominated by big bluestem (Andropogon gerardii), prairie dropseed (Sporobolus heterolepis), and little bluestem (Schizachyrium scoparium) [2,51]. In this alliance spiked muhly occurs in the pitch pine-white oak/prairie dropseed-big bluestem woodland in the Nantahala and Pisgah National Forests of North Carolina. This community occurs on shallow, rocky soils associated with outcrops of serpentinized olivine at moderate elevations on gentle to steep slopes with a western or southwestern exposure. The open, grassy woodland structure of this community is probably determined by a combination of site conditions and periodic disturbances (see Successional Status and FIRE REGIMES). The overstory composition and structure are likely maintained, at least in part, by the harsh soil conditions [51]. Spiked muhly occurred in a pitch pine-savanna on an olivine-serpentine outcrop in the Buck Creek area of western North Carolina in what appears to be a stable, edaphic climax. The serpentine soils have a higher cation exchange capacity and percentage base saturation, a lower pH, and a lower ratio of calcium to magnesium than other soils in the area [46]. The very rare ultramafic outcrop barren occurs predominantly on southerly exposures or flats. Ultramafic rocks have been associated with unusual vegetation and plant species, and most sites have vegetation of unusually small stature and openness for the climate. The barrens in North Carolina do not appear to have endemic species, but the best developed one supports numerous plant species, such as spiked muhly, that are rare in the region or rare throughout their range. These communities tend to be dry or xeric, with an open stunted canopy of xerophytic trees such as pitch pine (Pinus rigida), Virginia pine (P. virginiana), post oak, and southern red oak (Q. falcata); and a dense grassy herb layer with little bluestem, big bluestem, and prairie dropseed [63].
Spiked muhly was listed as a "distinguishing" or "characteristic" species in the Southern Appalachian bog and Southern Appalachian fen communities, respectively. Vegetation in the Southern Appalachian bog is a mosaic of shrub thickets and herb-dominated areas, much of it underlain by sphagnum mats. Trees such as red maple (Acer rubrum), eastern white pine (Pinus strobus), eastern hemlock (Tsuga canadensis), pitch pine, and red spruce (Picea rubens) may be scattered throughout or may dominate on the edges. Vegetation in the Southern Appalachian fen community is a mosaic of herbaceous wetland vegetation that varies with hydrology and substrate [63].
Western North America: Populations of spiked muhly in the West are scattered and generally occur in moist areas including fens [14,66], bogs [24,32,34], marshes, meadows, streambanks, shores of ponds and lakes [16,17,26,34,36,44], springs, and floating mats [34].
Though not as common as in the Great Lakes, spiked muhly may occur in fens and bogs in the West. Spiked muhly occurred in both flarks (pools of water) and strings (raised ridges) in minerotrophically rich fen communities in western Alberta. Its greatest abundance (frequency and cover) was on strings characterized by a tomentypnum moss-bog birch-tamarack (Tomentypnum nitens-Betula pumila var. glandulifera-Larix laricina) community type [66]. Spiked muhly is one of several rare plant populations occurring at Sema Meadows in the Kaniksu National Forest, in northeastern Washington. Sema Meadows is composed of fen communities dominated by sedges and sphagnum mosses and probably also includes some paludified conifer swamps on the forested margins. Much of the upland forest within the drainage is mature to old-growth western redcedar-western hemlock (Thuja plicata-Tsuga heterophylla) forest [14]. Spiked muhly was reported in a sphagnum bog in the Uinta Basin, Utah [24].
Spiked muhly often occurs in communities dominated by spikerushes (Eleocharis) or sedges (Carex spp.) in the West. It was listed among the sensitive and threatened species occurring in wetland and riparian habitats in National Forests of Washington state, with one recorded occurrence in the fewflower spikerush (E. quinqueflora) plant association [37]. In central and southwestern Montana, spiked muhly sometimes occurs in disturbed or early to mid-seral stands of the fewflower spikerush habitat type in wet basins and adjacent to streams, rivers, and ponds [29]. Along streams, rivers, lake margins, and reservoirs throughout Montana, it sometimes occurs in disturbed or early- to midseral stands of the common spikerush (E. palustris) community on sites prone to seasonal flooding. Spiked muhly sometimes occurs in late-seral to climax stands of the sageleaf willow/swollen beaked sedge (Salix candida/C. rostrata) habitat type, an incidental type occurring in the mountains of central and southwestern Montana. This community is restricted to anchored organic mats along pond and lake margins and is characterized by scattered clumps of sageleaf willow over a dense stand of swollen beaked sedge or water sedge (C. aquatilis) [29].
Along streams in Idaho, spiked muhly sometimes occurs in early- to midseral stands of the red-osier dogwood (Cornus sericea) community type on sites that are disturbed by livestock or wildlife. It does not occur on undisturbed sites, which tend to form a closed canopy of red-osier dogwood [28].
Spiked muhly typically occurs in relatively undisturbed sites (e.g., [6,8,38,44,48,75]), but also occurs in disturbed or early- to midseral stands in some communities (e.g., [13,28,29,70]). According to Werner and Zedler [75], spiked muhly has a coefficient of conservatism of 8, which is indicative of species that occur in relatively unaltered communities. Spiked muhly occurred at only 1 site in their study of 3 wetlands in south-central Wisconsin that have a history of urban stormwater inputs and sediment accumulation. It had 0.5% average cover in the native sedge community but did not occur in communities dominated by stands of invasive canarygrass (Phalaris) or cattail (Typha) or in communities transitioning from native to invasive dominance [75]. Its absence from invasive-dominated communities may be due to shading from and competition for sunlight with the large-statured, dominant grasses (see Shade tolerance). According to Lavin and Seibert [44], spiked muhly occurs in undisturbed wet sites in western Montana, whereas green muhly occurs in disturbed areas in generally dried-out, previously wet sites in central and eastern Montana. However, in Montana and Idaho, Hansen and others [28,29] identified spiked muhly in late-seral to climax stands of the sageleaf willow/swollen beaked sedge habitat type, as well as in early to midseral stands in communities disturbed by livestock and wildlife (see Grazing). Spiked muhly is also noted in communities disturbed by fire (e.g., [12,13]), suggesting that it is an early- to midseral species in some communities.
Shade tolerance: Very few articles in the available literature (as of 2011) address shade tolerance in spiked muhly. It is reported to occur in partial shade to full sun in southern Wisconsin [3]. In boreal and sub-boreal fens across northern Ontario, it appears that shade from woody species prevented spiked muhly occurrence on hummocks; the minimum light intensity where spiked muhly was present was about 32% of full sunlight at 12 inches (30 cm) above the moss surface [40].
Postfire succession: Spiked muhly is a characteristic species in alvar communities in the Great Lakes region [10] and is thought to be more frequent on successional alvar burns than in any other natural habitat in the Ottawa-Carleton region [11]. In the Burnt Lands Alvar, on an extensive limestone plateau in eastern Ontario, spiked muhly occurred with low cover and frequency on unburned sites (no fire in 129 years) and in early postfire succession (100 days after severe fire) [12], but it increased in abundance 16 months after fire [13]. The highest frequency of spiked muhly in this series of studies occurred in a different area burned 37 years prior to sampling [11]. Both areas were forested before the fires. Dominant species included northern whitecedar, quaking aspen, balsam fir, white spruce, and eastern white pine [11,12]. Spiked muhly had intermediate cover and frequency on bulldozed plots 465 days after the bulldozing, which was done in connection with the fire control [13].
In North Carolina, spiked muhly occurs in communities that may be influenced by periodic fire, although the presettlement fire frequencies in these communities are not known. In the Nantahala and Pisgah National Forests, spiked muhly occurs in the pitch pine-white oak/prairie dropseed-big bluestem woodland. The open, grassy woodland structure of this community is probably determined by a combination of site conditions (e.g., harsh soil conditions) and periodic disturbances such as fire. The dry, grassy vegetation is flammable, and periodic fire is thought to maintain the grass-dominated understory. In the absence of occasional fire, shrub density increases and herbaceous cover decreases. In the last 30 years of the 20th century, the overstory in this community was significantly reduced by infestations of southern pine beetle [51]. In the rare ultramafic outcrop barren community in North Carolina, an open, stunted canopy of xerophytic trees such as pitch pine, Virginia pine, post oak, and southern red oak is underlain by a dry, flammable herb layer with little bluestem, big bluestem, and prairie dropseed. Periodic fires would likely maintain the open nature of this community, and the harsh environment may allow only slow recovery of woody plants after fire. The barren community may be more affected by fire than surrounding communities on more favorable sites [63].
Grazing: Spiked muhly seems to be an early- to midseral species in some communities disturbed by grazing animals. Hansen and others [28,29] identified spiked muhly in communities disturbed by livestock and wildlife; these included spikerush communities in Montana [29] and red-osier dogwood communities in Idaho [28]. In the Saskatchewan prairie ecozone, spiked muhly occurred in a water birch community type on sites disturbed by livestock or wildlife. Heavy grazing prevented successful water birch regeneration, reduced or eliminated other desirable shrubs, and allowed an increase of disturbance-related herbaceous species, including spiked muhly [70]. In calcareous fens in southern Wisconsin, spiked muhly cover was significantly greater on animal trails in one study, but it was not consistently associated with animal trails in another [9].
Spiked muhly occurs in the Southern Appalachian bog community where grazing has been nearly universal and there are few bogs in pristine condition. Most bogs are experiencing invasions or increases of woody species, which threaten to eliminate many of the herbaceous species. The tendency toward rapid succession suggests that some form of periodic or chronic natural disturbance, now disrupted, may have kept the bogs open. Potential disturbances include flooding by American beavers, grazing by herds of large mammals, fire, and clearing by American Indians. An alternative hypothesis is that the unfavorable environment and competition from established herbaceous vegetation originally limited tree and shrub establishment, but recent modifications such as heavy grazing, ground water pumping, and increased nutrient input have changed these conditions [63].
The scientific name of spiked muhly is Muhlenbergia glomerata (Willd.) Trin. (Poaceae) [5,16,23,25,31,32,35,45,58,64,74]. It is in the subgenus Muhlenbergia [55].
Pohl [55] reports that spiked muhly frequently hybridizes with Mexican muhly (M. mexicana). These species occur together in many habitats. Three instances of possible hybridization of spiked muhly with foxtail muhly (M. andina) have also been detected; 2 from Flathead Lake, Montana, and 1
from Lacombe, Alberta [55]. According to Gleason and Cronquist [22], spiked muhly hybridizes with green muhly; however Pohl's review [55] does not support this assertion.
Some authors have indicated that spiked muhly is not readily separable from green muhly
(M. racemosa) (e.g., [32,33,74]) and suggest that it is sufficient to lump them. However, cytological [55,56], morphological (see Botanical description), and ecological (see Site Characteristics and Plant Communities) differences exist between these 2 species, so they are treated separately in the Fire Effects Information System. For information from the literature pertaining to green muhly, see its FEIS review. Because some authors cited in these reviews may have
lumped or misidentified these 2 species, some information in this review may pertain to green muhly and vice versa.
Muhlenbergia glomerata is a species of grass known as spiked muhly and marsh muhly. It is native to North America, where it occurs across Canada and the northern half of the United States.[2][3]
This grass produces branching stems up to 1.2 meters tall from a network of rhizomes. The inflorescence is a narrow panicle of spikelets which are up to 8 millimeters long.[2][4]
This North American grass is found in moist areas in various habitat types. It grows in bogs, marshes, meadows, ditches, fens, swamps, riversides and lakeshores, hot springs, wet forests, alvars, and seasonally flooded land. It occurs in cooler, more moist places than many other C4 species. It occurs less often in dry places.[2]
Muhlenbergia glomerata is a species of grass known as spiked muhly and marsh muhly. It is native to North America, where it occurs across Canada and the northern half of the United States.
Agrostis festucoides é uma espécie de gramínea do gênero Agrostis, pertencente à família Poaceae.[1]
Muhlenbergia glomerata là một loài thực vật có hoa trong họ Hòa thảo. Loài này được (Willd.) Trin. mô tả khoa học đầu tiên năm 1824.[1]
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Muhlenbergia glomerata là một loài thực vật có hoa trong họ Hòa thảo. Loài này được (Willd.) Trin. mô tả khoa học đầu tiên năm 1824.
