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On 28 June 1977 a human-caused fire burned 121 acres (49 ha) of rough fescue (Festuca altaica)-Idaho
fescue-bluebunch wheatgrass dominated grasslands on Mount Sentinel in Missoula, Montana. At the time of the
fire, winds averaged 23 km/hr. with gust to 55 km/hr, relative humidity was 31%, and the air temperature
approximately 81 °F (27 °C) [118]. The site burned was ungrazed and had been fire-free for at least 32 years.
The fire consumed almost all aboveground vegetation and many bunchgrass clumps were burned to belowground level.
Samples taken on Mount Sentinel 4 months, 11 months, and 1 year postfire showed that the fire reduced threadleaf
sedge cover. By postfire year 3, cover of threadleaf sedge on burned sites was only 60% of that on unburned sites.
While the fire caused a reduction in cover, threadleaf sedge occurrence on and off the burn site is very low and
the authors do not discuss whether the difference is significant [4].
Burning Date
On the mixed-grass prairies of eastern Montana near Miles City, spring (3
April) and fall burning (2nd week of October) had different effects on the production (lbs./acre)
of threadleaf sedge. Sites burned on 3 April produced less threadleaf sedge than
unburned sites during 3 of the first 4 measurement dates. Until
approximately mid-June, production on fall-burned sites was significantly
(p<0.05) lower than on control and spring-burned sites. The following
table describes the production of threadleaf sedge on unburned, spring-burned,
and fall-burned plots on 7 dates during the 1979 growing season [189,190]:
Date
This description provides characteristics that may be relevant to fire ecology, and is not meant for identification. Keys for identification are available (e.g. [3,17,44,82,89,90,96,108,129,182]).
Threadleaf sedge is a cool-season, sod-forming, drought-resistant, low-growing, native perennial graminoid [2,32,71,72,107,107,160,164,170,173]. It is densely tufted, with numerous leaf-bearing sheaths at the base [44,90,96,108,116,129,182] and grows in bunches approximately 4 to 6 inches (10-15 cm) in width [38,179]. Threadleaf sedge culms are slender, stiff and wiry [44,90], often curved [96], and 2 to 15 inches (5-38 cm) tall [3,17,44,71,82,90,108,129,182]. Leaves are mostly basal, stiff, strongly folded, very slender [44,90,108], and 1 to 8 inches (3-20 cm) long and 0.25 to 0.5 mm wide [3,17,71,82,129,182]. Threadleaf sedge is one of the few Carex spp. to contain alkaloids [85].
Threadleaf sedge is monoecious [165,173]. The spikelets are 0.4 to 1 inch (1-3 cm) long [3,44,82,90,108,129,182], up to 6 mm wide [44,82,90], and 3- to 25-flowered [165]. The flowers of threadleaf sedge are unisexual [17,44,71,82,90,116,129,165,182]. Fruits are achenes, 2.25 to 3 mm long and weigh approximately 2.9 mg [3,165].
The roots of threadleaf sedge are tough, wiry, and 0.8 mm or less in diameter [40,164]. Roots occur in "enormous numbers" and seldom descend vertically, but run away from and under the plant to distances of 2 to 2.5 feet (0.6-0.8 m) [26,179].
Eight threadleaf sedge plants excavated from a Saskatchewan grassland were found to grow obliquely downward in all directions to form a dense mat in the upper 12 inches (30 cm) of soil. The dense mat spread out as much as 15 inches (38 cm) from the base of the plant. The roots were profusely branched, excluding those closest to the crown. The longest lateral roots measured were 2 inches (5 cm). Most of the roots terminated growth at 12 to 24 inches (30-60 cm) below ground surface, though some were found to penetrate 30 inches (75 cm) below soil surface. At the point of termination, threadleaf sedge roots are densely branched with brush-like ends. Plants excavated in Colorado and South Dakota have exhibited a rooting depth of 5.2 feet (1.6 m) and a lateral spread of 32 inches (80 cm) [40].
Fire adaptations: Threadleaf sedge establishes after fire by seed and/or by tillering from basal meristem tissue which is protected from fire by soil and/or damp litter [4,50,128,178,185,186,187,189,190]. Since establishing from seed is generally rare in this species [72,170], postfire seedling establishment may be uncommon.
FIRE REGIMES: Threadleaf sedge is found in the sagebrush (Artemisia spp.)-grasslands of the northern Great Basin, in the mixed-grass prairies of the northern Great Plains, and in the mixed forests of the Cascade, Sierra Nevada, and northern Rocky Mountains, which exhibit a wide range of historic fire frequencies.
Mixed forests: On the leeward slope of the southern Cascade Mountains in northeastern California, threadleaf sedge is a dominant species in meadows fringed by Pacific ponderosa pine (Pinus ponderosa var. ponderosa), Jeffrey pine (P. jeffreyi), Sierra lodgepole pine (P. contorta var. murrayana), and western juniper. Using fire scar and tree ring data in 8 meadow units, Norman and Taylor [132] constructed a fire history of the area for the years 1700 to 1849. During this period widespread fire burned 7 or more meadow units with a return interval of 7 to 49 years. Moderately widespread fires burned 4 or more units during this period 19 times with a return interval of 2 to 22 years. Fire burned in at least 1 meadow unit during this period in 93 of 150 years. Between 1785 and 1835, on 3 occasions there were periods of 2 to 6 years without fire [132].
Northern Great Plains: Historically fire has played an important role in the northern Great Plains. The large tracts of continuous mixed-grass prairie, which occur in hot, dry areas and accumulate much fine fuel, are susceptible to frequent lightning fires. Higgins [88] estimates that 6 lightning fires consuming 4,000 miles² (10,000 km²) of grasslands occurred a year in eastern North Dakota, and 25 lightning fires consuming 4,000 miles² (10,000 km²) of grasslands occurred a year in western North Dakota. Early records kept by explorers, trappers, and settlers note a high occurrence of fires, both natural and anthropogenic, with fires occurring at intervals of 5 to 10 years [46,135,153,156,192]. Since the early 1900s, fire has been excluded, allowing nonnative species such as Japanese brome, smooth brome (Bromus inermis), Kentucky bluegrass (Poa pratensis), crested wheatgrass (Agropyron cristatum), and Canada thistle (Cirsium arvense) to take a strong hold in the area [46].
Sagebrush-grasslands: Fire in the sagebrush-grasslands of the northern Great Basin where threadleaf sedge grows likely occurred with a frequency of 20 to 70 years [135]. Wright and others [192] hypothesize that fires likely occurred about every 50 years. Changes in land use and management practices, such as the invasion of cheatgrass, have altered the fire return interval to less than 10 years in some areas [133,135].
Shrub-steppe: Threadleaf sedge is found across the Columbia Plateau of Oregon, Washington, and Idaho. The fire return interval for this habitat is approximately 25 years [43].
The following table provides fire return intervals for plant communities and ecosystems where threadleaf sedge is important. Find 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".
Community or ecosystem Dominant species Fire return interval range (years) bluestem prairie Andropogon gerardii var. gerardii-Schizachyrium scoparium 105,135] Nebraska sandhills prairie Andropogon gerardii var. paucipilus-Schizachyrium scoparium 135] silver sagebrush steppe Artemisia cana 5-45 [87,140,192] sagebrush steppe Artemisia tridentata/Pseudoroegneria spicata 20-70 [135] basin big sagebrush Artemisia tridentata var. tridentata 12-43 [150] mountain big sagebrush Artemisia tridentata var. vaseyana 15-40 [7,24,124] Wyoming big sagebrush Artemisia tridentata var. wyomingensis 10-70 (µ=40) [176,197] desert grasslands Bouteloua eriopoda and/or Pleuraphis mutica 10 to <100 [121,135] plains grasslands Bouteloua spp. 135,192] blue grama-needle-and-thread grass-western wheatgrass Bouteloua gracilis-Hesperostipa comata-Pascopyrum smithii 135,149,192] blue grama-buffalo grass Bouteloua gracilis-Buchloe dactyloides 135,192] cheatgrass Bromus tectorum 138,183] western juniper Juniperus occidentalis 20-70 Rocky Mountain juniper Juniperus scopulorum <35 [135] wheatgrass plains grasslands Pascopyrum smithii <5-47+ [135,140,192] Engelmann spruce-subalpine fir Picea engelmannii-Abies lasiocarpa 35 to >200 [6] pinyon-juniper Pinus-Juniperus spp. <35 [135] Rocky Mountain lodgepole pine* Pinus contorta var. latifolia 25-340 [10,11,168] Sierra lodgepole pine* Pinus contorta var. murrayana 35-200 [6] Colorado pinyon Pinus edulis 10-400+ [60,70,103,135] Jeffrey pine Pinus jeffreyi 5-30 Pacific ponderosa pine* Pinus ponderosa var. ponderosa 1-47 [6] interior ponderosa pine* Pinus ponderosa var. scopulorum 2-30 [6,9,112] quaking aspen (west of the Great Plains) Populus tremuloides 7-120 [6,73,122] mountain grasslands Pseudoroegneria spicata 3-40 (µ=10) [5,6] Rocky Mountain Douglas-fir* Pseudotsuga menziesii var. glauca 25-100 [6,7,8] California mixed evergreen Pseudotsuga menziesii var. menziesii-Lithocarpus densiflorus-Arbutus menziesii <35 [6] little bluestem-grama prairie Schizachyrium scoparium-Bouteloua spp. <35 [135] *fire return interval varies widely; trends in variation are noted in the species reviewThe research described above suggests that prescription burning may or may not favor threadleaf sedge. If fire is used to manage threadleaf sedge land managers should use caution and follow the guidelines addressed below.
Grazing: Burned rangelands containing threadleaf sedge should be protected from grazing during postfire year 1 to allow for uninterrupted growth of herbaceous vegetation [15,21,189].
Invasive species: Improper fire management may convert desirable shrub and perennial grass stands to annual grass and invasive shrub stands [184,193]. Wright and others [193] suggest that if fires occur in big sagebrush (A. tridentata)-grasslands at a frequency of less than every 50 years, the communities may become dominated by rubber rabbitbrush (Chrysothamnusnauseosus) and gray horsebrush (Tetradymia canescens), sprouting species that respond vigorously to fire. Cheatgrass may also expand after fire and severely reduce native plant coverage [137,184,193].
Precipitation: Two authors suggest that it is harmful to burn threadleaf sedge during drought years [186,189].
Sagebrush-grassland communities: Threadleaf sedge occurs in sagebrush-grasslands with species that can be harmed by fire [184]. June or July fires can be especially harmful to Idaho fescue and needle-and-thread grass [15,192]. Big sagebrush is slow to recover from extensive fires [15].
Threadleaf sedge is generally found on warm, dry, well-drained, upper south-facing slopes [16,25,125,145]. Literature on threadleaf sedge describes it occurring on dry ridges [96,173], dry open places and dry meadows [44,90], dry rocky slopes and flats [100,129], dry plains and valleys [17,116,180,181], dry grasslands [108,180,181], and upland prairies [71,114]. Threadleaf sedge also grows on the tundra-steppe of Alaska on sites with favorable southern exposures [56,130].
Climate: Threadleaf sedge thrives under a continental climate regime in which 80% of precipitation falls during the growing season (April-September) [1,14,145]. Threadleaf sedge requires a minimum of 90 frost-free days and favors from 8 to 24 inches (200-610 mm) of average annual precipitation [174]. On the mixed-grass prairies of North Dakota where threadleaf sedge is often dominant, temperature extremes range from 109 °F (43 °C) in the summer to Â47 °F (Â44 °C) in winter [59].
During the 1934 growing season, grasslands around Miles City, Montana, experienced a historic drought. Rainfall during the 1934 growing season was 3.53 inches (89.7 mm), down from a 57-year average of 9.32 inches (237 mm). Consequentially, threadleaf sedge plants were markedly shorter than in normal precipitation years and production was down 17% [57]. Near Mildred, Montana, the drought caused a significant (p<0.05) decrease in threadleaf sedge. Production of threadleaf sedge was reduced by 12% to 55% on silty and sandy sites [188].
Near Virginia City, Montana, cool July soil temperatures correlated (r = Â0.77) with increased production of threadleaf sedge. The soil temperature was measured as electrical resistance, thus a negative coefficient meant a positive relationship with soil temperature. However, windy May conditions correlated (r = Â0.83) with decreased growth in threadleaf sedge [127].
Elevation: Elevational ranges for threadleaf sedge are presented below:
State/Province Elevation Alaska Up to 5,000 feet [56,96] Arizona Up to 6,500 feet [102] California Up to 11,000 feet [55,125] Colorado 5,000 to 7,500 feet [82] Montana 1,900 to 9,200 feet [1,45,63,126,127] Nevada 5,000 to 8,500 feet [100] New Mexico 5,000 to 7,000 feet [116] North Dakota 1,000 to 2,600 feet [48,81] Oregon Up to 4,500 feet [66] South Dakota 900 to 7,200 feet [65,83,104] Utah 5,000 to 7,300 feet [69,182] Wyoming 5,400 to 9,200 feet [42,119] Alberta 800 to 4,000 feet Manitoba 800 to 4,000 feet Saskatchewan 800 to 4,000 feet [38] Yukon Territory 3,000 to 6,300 feet [91]
Soil: Threadleaf sedge is often found on well-drained, silty clay loam [45,49] and fine sandy loam soil [25,81]. On the Canadian mixed-grass prairie, threadleaf sedge grows on clay loam, loam, and light loam soils. Approximately 65% of threadleaf sedge growth occurs on light loam soils [38,95]. Threadleaf sedge can tolerate saline soils. On the Central Plains Experimental Range, Colorado, it occurs in saltgrass meadows in limited quantities on soils with a pH as high as 9.2 [120].
A month-by-month soil chemical analysis of a threadleaf sedge-dominated community in the Badlands of North Dakota is presented by Fairaizl [59].
A detailed review on soil constituents of a threadleaf sedge/western wheatgrass and a threadleaf sedge/blue grama/needle-and-thread grass community in western North Dakota is presented by Hanson and Whitman [81].
Threadleaf sedge is one of the most important grass-like forage species on the northern Great Plains [92,164]. It is particularly important due to its early growth and high palatability in the spring [35,42,146,151,164]. Threadleaf sedge is eaten readily by cattle and domestic sheep when it is young, but is avoided as it ages and becomes tough [109,136,151].
From the end of November to the end of April on rangelands north of Nunn, Colorado, threadleaf sedge and needleleaf sedge constitute 18% of cattle diets on sandy plains and overflow sites and 22% on loamy plain sites. From the 1st of June to the middle of October, the 2 sedges constitute 6% of diets on sandy plains and overflow sites and 12% on loamy plain sites [155]. Threadleaf sedge is preferentially grazed in the early spring by feral horses in south-central Wyoming. In spring 1991, threadleaf sedge composed 62% of their early spring diet [42].
Small mammals/birds: The seeds, leaves, and roots of threadleaf sedge are eaten by fur and game mammals, small mammals, and birds [115]. Threadleaf sedge is an important food source for black-tailed prairie dogs in western South Dakota. Research collected on their food habits in 1973 found that threadleaf sedge constitutes from 9% to 19% of black-tailed prairie dog diets [166]. In eastern Montana, threadleaf sedge-western wheatgrass-blue grama communities provide the most important habitat for sharp-tailed grouse [167].
Ungulates: Threadleaf sedge is utilized by ungulates [115]. It is the most important forage graminoid for bighorn sheep in the Badlands of North Dakota during the spring. Threadleaf sedge constitutes 28.8% of bighorn sheep diets in the spring, yet it is only 1.8%, 0.0%, and 0.1% of their diet during the winter, summer, and fall, respectively [59]. Threadleaf sedge is an important forage species for pronghorn and American bison in the Wind Cave National Park, South Dakota, [196] and Dall sheep in the Sheep Mountains, Yukon Territory [91]. Elk in the southern unit of the Theodore Roosevelt National Park, North Dakota, utilize threadleaf sedge as a forage species [172]. Threadleaf sedge is an important winter and spring forage species for elk in Wind Cave National Park, South Dakota. During the winter and spring, threadleaf sedge constitutes 12.6% and 38.6%, respectively, of elk diets. It is of marginal use during the fall (4.2%) and of no use during the summer [195,196].
Palatability/nutritional value: The palatability of threadleaf sedge early in the growing season is high, but as it becomes dry and tough by the middle of summer its palatability is very low [93,113,175].
The palatability of threadleaf sedge in the National Forests of Region 1, which cover more than 23,000,000 acres (9,308,000 ha) in South Dakota, Montana, Idaho, and Washington, is rated as 60 on a scale of 0 to 100 [63]. Palatability of threadleaf sedge on the northern Great Plains is rated as 70 [151].
The palatability of threadleaf sedge for livestock and wildlife is rated as follows [47]:
Species Colorado Montana North Dakota Utah Wyoming cattle fair good good fair fair domestic sheep good good good fair good horses good good good fair fair elk --- fair --- fair good mule deer --- poor good fair fair white-tailed deer fair good --- --- --- pronghorn --- poor good fair fair upland game birds --- --- --- fair --- waterfowl --- fair --- poor --- small nongame birds --- --- --- fair --- small mammals --- --- --- fair good
Threadleaf sedge is one of the highest protein grass and/or grass-like species in the northern Great Plains [170]. The crude protein value of threadleaf sedge decreases from a high of 12.38% in early June to a low of 5.6% in August [93]. Cows nursing calves require a total protein level of 9.2%. Threadleaf sedge meets this requirement on the Great Plains from the resumption of spring growth until approximately 20 June. Dry pregnant mature cows require 5.9% total protein in their diets and threadleaf sedge meets this requirement throughout the year [164].
The nutritive content of threadleaf sedge at the Cottonwood Range Field Station in southwestern South Dakota during the growing season is presented below [32]:
Date Protein (%) Holocellulose (%) Hemicellulose (%) Cellulose (%) Fiber (%) Lignin (%) 17 June 11.4 58.3 38.9 24.4 29.4 3.2 28 June 9.6 55.9 39.8 24.4 29.3 3.2 17 July 7.8 57.4 35.4 25.4 31.7 4.0 16 August 6.0 61.0 37.6 27.6 35.6 3.8 13 September 4.3 69.2 41.2 31.8 41.9 4.8
The chemical composition of threadleaf sedge given as a range during the 1976 growing season at 3 sites (Sidehill, Flat Top Ridge, and Creek Bottom) in the Badlands of North Dakota is given below. For a more detailed analysis see the review by Fairaizl [59].
Month Ca (%) Mg (%) K (%) April 0.66-0.74 0.15-0.23 0.58-0.99 May 0.58-0.88 0.14-0.23 0.63-0.32 June 0.73-1.11 0.17-0.29 0.89-1.11 July 0.89-1.05 0.20-0.32 0.80-0.89 August 0.90-1.05 0.14-0.27 0.71-1.05 September 0.76-0.91 0.13-0.18 0.29-0.35
The nutritive content of threadleaf sedge during bloom stage near Sundance, Wyoming, is presented in the table below [77]:
Ash (%) Crude protein (%) Ether extract (%) Crude fiber (%) N-free extract (%) Gross energy (Kcal/g) 8.94 12.57 2.42 29.56 46.51 4.31
Cover value: Threadleaf sedge is a low-growing species and therefore has limited cover value [2,32,71,72,107,107,160,164,170,173].
Small mammals/birds: Threadleaf sedge provides principal cover for mountain plover nesting sites in southeastern Campbell County, northern Converse County, and a small portion of southwestern Weston County, Wyoming [134]. It provides cover for a large number of bird species in the Columbia Basin of Washington [51] and on the mixed-grass prairies of the Scott's Bluff National Monument, Nebraska [41].
Threadleaf sedge provides cover for black-tailed prairie dogs on the grasslands of the Black Hills, South Dakota [104] and in Billings County, North Dakota [163]. The Oregon ground squirrel builds its burrows in northeastern California in threadleaf sedge stands on sandy sites [173].
Threadleaf sedge is listed as a dominant species in the following vegetation
classifications:
United States
CA:
Yosemite National Park meadows (monotypic community) [33,55]
CO:
Central Plains Experimental Range (codominant with saltgrass (Distichlis spicata),
alkali sacaton (Sporobolus airoides), blue grama (Bouteloua gracilis), and
western wheatgrass (Pascopyrum smithii)) [120]
Pawnee National Grasslands (codominant with broom snakeweed (Gutierrezia sarothrae),
blue grama, and scarlet globemallow (Sphaeralcea coccinea)) [123]
ID:
Upper Snake River Plains (codominant with Idaho fescue (Festuca idahoensis)) [128]
KS:
Northern mixed-prairie (codominant with blue grama and needle-and-thread grass (Hesperostipa
comata)) [111]
MT:
Fort Keogh Livestock and Range Research Laboratory (codominant with needle-and-thread grass,
blue grama, Sandberg bluegrass (Poa secunda), sand dropseed (Sporobolus cryptandrus),
and Japanese brome (Bromus japonicus)) [45,74,75,76]
Havre (codominant with blue grama and needle-and-thread grass) [86]
Glendive mixed-grass prairie (codominant with western wheatgrass and blue grama) [167]
Square Butte (codominant with blue grama and bluebunch wheatgrass (Pseudoroegneria spicata))
[194]
Custer National Forest (codominant with needle-and-thread grass, western wheatgrass, little bluestem,
bluebunch wheatgrass, and fragrant sumac (Rhus aromatica)) [78]
Bull Mountains, Gravelly Range, and Pioneer Mountains (codominant with Idaho fescue) [126]
ND:
Dickinson Research Center mixed-grass prairie (codominant with western wheatgrass, prairie Junegrass
(Koeleria macrantha), needle-and-thread grass, green needlegrass (Nassella viridula),
and sun sedge (Carex heliophila)) [14]
Billings County mixed-grass prairie (codominant with blue grama and needle-and-thread grass) [18]
Little Missouri Badlands mixed-grass prairie (codominant with western wheatgrass, needle-and-thread grass,
and blue grama) [20,49]
Nelson County (codominant with needle-and-thread grass, blue grama, and western
wheatgrass) [48]
Sentinel Butte (codominant with blue grama, western wheatgrass, and needle-and-thread grass) [81]
Theodore Roosevelt National Memorial Park (codominant with blue grama, western wheatgrass, green
needlegrass, and needle-and-thread grass) [79,84]
Ranger (codominant with interior ponderosa pine (Pinus ponderosa var. scopulorum),
western wheatgrass, blue grama, and needle-and-thread grass) [139]
Northern Great Plains Field Station (codominant with blue grama, western wheatgrass, and needle-and-thread
grass) [144]
NE:
Scotts Bluff National Monument grasslands (codominant with needle-and-thread grass, western wheatgrass,
cheatgrass (B. tectorum), sideoats grama (Bouteloua curtipendula), and prairie sandreed
(Calamovilfa longifolia)) [41]
Cherry County (codominant with needle-and-thread grass) [171]
Cedar Point Biological Station (codominant with blue grama) [101]
OR:
Horse Ridge (codominant with western juniper (Juniperus occidentalis) and mountain big sagebrush
(Artemisia tridentata ssp. vaseyana)) [62,66]
SD:
Black Hills (codominant with needle-and-thread grass, western wheatgrass, prairie Junegrass, blue grama,
buffalo grass (Buchloe dactyloides), needleleaf sedge (Carex duriuscula), and bluebunch
wheatgrass) [83]
Pine Ridge Indian Reservation (codominant with blue grama, western wheatgrass, needle-and-thread grass,
and needleleaf sedge) [110]
Wind Cave National Park (codominant with big bluestem (Andropogon gerardii var. gerardii)
and little bluestem (Schizachyrium scoparium)) [196]
Badlands National Park (codominant with little bluestem, blue grama, and skunkbush sumac (R. trilobata))
[46]
Custer National Forest (codominant with needle-and-thread grass, western wheatgrass, little bluestem,
bluebunch wheatgrass, and fragrant sumac) [78]
WY:
Shirley Basin (codominant with blue grama, western wheatgrass, needle-and-thread grass, bluebunch wheatgrass,
Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis), and fringed sagebrush
(A. frigida)) [94]
Knife River Indian Villages National Historic Site (codominant with needle-and-thread grass, blue grama,
prairie Junegrass, and western wheatgrass) [30]
Cheyenne (codominant with bluebunch wheatgrass and blue grama) [34]
Powder Rim (codominant with needle-and-thread grass) [131]
Cheyenne River Basin (codominant with blue grama) [169]
Regions:
Interior Columbia Basin (codominant with Idaho fescue) [23]
Northern Great Plains (codominant with blue grama and needle-and-thread grass) [39]
Great Plains shrubland (codominant with Wyoming big sagebrush) [152]
Canada
AB:
Southern provincial short-grass prairie (codominant with blue grama and Sandberg
bluegrass) [31]
Agriculture Canada Research Substation (codominant with needle-and-thread grass,
western wheatgrass, blue grama, Sandberg's bluegrass, and prairie Junegrass) [159]
SK:
Southwestern provincial short-grass prairie (codominants include blue grama and
Sandberg bluegrass) [31]
YK:
Aishihik-Sekulmun lakes area grasslands (codominant with fringed sagebrush) [177]
Disturbance:
Soil disturbance may have long-lasting negative effects of threadleaf sedge. In 1976 the
basal cover (%) and mean aboveground production (g/m²) of threadleaf sedge was investigated
on 4 plowed (P) and unplowed (U) sites on the mixed-grass prairie of southwestern North Dakota.
The plowed sites were formerly farmland which had been abandoned and unworked for 40 years.
Threadleaf sedge basal cover and mean aboveground production was greater on unplowed than plowed
sites [19].
Forage production:
Threadleaf sedge production is 2nd only to bluebunch wheatgrass, which has a forage production
value of 341.8 lbs./acre, on the Palouse Prairie of eastern Washington [117]. On the northern
Great Plains, the average forage yield of threadleaf sedge is approximately 40 lbs./acre [39].
Threadleaf sedge has a forage production of 308.3 lbs./acre on silty loam soil outside of Davenport,
Washington. On grasslands southwest of Virginia City, Montana, the herbage production of threadleaf
sedge for the 10-year period 1964 to 1973 ranged from 27 to 51 lbs./acre on southwest exposure sites
and 1 to 12 lbs./acre on northeast exposure sites [127].
Across its range, threadleaf sedge generally flowers from April to May [22,69,90,125,165]. In dry grasslands, threadleaf sedge is considered an "early bird" species in a phenological sense because it flowers early and reaches annual maximum growth before other associated forage species [91,151,171]. On the northern Great Plains, threadleaf sedge begins growing in middle to late March. On 15 May the average leaf height is 4.2 inches (10.7 cm) and achieves a maximum leaf height of 5.0 inches (13 cm) by 10 June [92].On the mixed-grass prairies of Alberta, Saskatchewan, and Manitoba, threadleaf sedge begins growth during the 1st week of April and the heads appear by the end of the month. Flowering occurs by mid-May, with seeds shedding by the 1st of July [38].
From 1946 to 1954 flowering data were collected on threadleaf sedge at the Experimental Farm, Swift Current, Saskatchewan. On average, threadleaf sedge begins flowering on 7 May, with the earliest and latest flowering dates occurring on 25 April and 25 May, respectively. The latest threadleaf sedge was observed in flower was 19 June and the mean flowering period was 30 days [22].
At the Dickinson Experimental Station in western North Dakota, threadleaf sedge mean leaf and stalk heights from April through June were measured and averaged for an 8-year period (1955-1962) and are presented in the table below [67]:
April May June 8 15 22 29 1 8 15 22 29 1 8 15 22 Mean leaf height (cm) 1.5 3.0 3.0 5.5 6.3 7.0 8.2 8.9 10.1 10.3 10.4 10.4 10.6 Mean stalk height (cm) ---* --- --- 2.5 4.0 6.5 8.8 11.7 11.8 12.2 13.0 13.4 14.4 *No data
The phenological development of threadleaf sedge at the Cottonwood Range Field Station in southwestern South Dakota is presented below [32]:
Date Phenological stage June 17 Early vegetative June 28 Vegetative July 17 Seed ripe August 16 Shattered September 13 Dormant
The phenological of development of threadleaf sedge was investigated at 5 elevations on Sheep Mountain, Yukon Territory. Plants developed faster at an elevation of 3,280 feet (1,000 m) than plants at 3,068 feet (935 m). The author suggests that the threadleaf sedge plants grew slower at 3,068 feet (935 m) than at 3,280 feet (1,000 m) due to shadows cast by surrounding trees. The following table shows the date threadleaf sedge plants achieved maximum height at 5 different elevations [91]:
Date Elevation 30 June 935 m 18 June 1,000 m 26 June 1,330 m 5 July 1,590 m 15 July 1,910 m
Threadleaf sedge recovers from fire by tillering and/or establishing from seed [4,50,128,178,185,186, 187,189,190]. Threadleaf sedge seed dispersal onto burned sites is likely affected by wind. While threadleaf sedge may utilize a seed bank [29], as of this study (2006), there is a lack of information on seed tolerance to fire.
Several authors list threadleaf sedge as a plant severely damaged by fire [21,137,142,142,157,191, 193]. However, this is based on 1 review by Blaisdell [15] of a prescribed fire on the upper Snake River Plains of Idaho in which he did not differentiate between sedge species. The research presented below provides mixed results on the effects of fire on threadleaf sedge and disputes the generalization that it is severely damaged by fire. In an unpublished report, Whisenant and Uresk [185] state that it takes threadleaf sedge plants approximately 2.5 years to reach reproductive maturity after fire.
Threadleaf sedge generally reproduces vegetatively via tillers, but does produce some viable seeds [72,93,165].
Pollination: Threadleaf sedge is wind pollinated [28].
Breeding system: Threadleaf sedge is monoecious [165,173].
Seed production: Threadleaf sedge produces very few viable seeds each year [72,170]. In the northern Great Plains, threadleaf sedge generally produces a poor seed crop since it flowers early and is susceptible to frost damage [151]. A threadleaf sedge plant collected in North Dakota contained a total of 232 seeds (viability not discussed) [161].
Seed dispersal: The seeds of threadleaf sedge are likely dispersed by wind.
Seed banking: Threadleaf sedge utilizes a soil seed bank [29].
Germination: In the field, threadleaf sedge seeds have a low rate of germination [72,170]. In a controlled study, stratified threadleaf sedge seeds did not germinate significantly (p<0.05) better than control seeds (33.3%). Scarification of threadleaf sedge seeds caused a significantly lower rate of germination than control seeds. Seeds that were cold-moist stratified at 41ºF (5 ºC) had germination rate of 25.3% to 40.1%, while seeds frozen-moist stratified at 19 ºF (− 7 ºC) had a germination rate 28.1% to 38.2%. Threadleaf sedge scarified with a razor germinated at a rate of 22.6% [72]. Threadleaf sedge seed viability does not decrease for at least 14 to 17 months when dry stored at room temperature [170].
Seedling establishment/growth: Threadleaf sedge seedlings in nature are rare [72,170]. On the northern Great Plains, seedlings of threadleaf sedge establish by the middle of March and grow to maturity by the 1st to middle of June [93]. To evaluate the establishment of seedlings, Griffin [72] planted threadleaf sedge plugs on the grasslands of Scotts Bluff National Monument, Nebraska. Griffin planted sod plugs in fall (28 September to 3 October), late winter (6 March), and spring (26 to 27 May). At the end of 2 years of observations, the average rate of survival by seedlings was only 0.94%.
Asexual regeneration: Threadleaf sedge reproduces asexually from tillers [93,165].
Threadleaf sedge can survive on disturbed sites, such as burns [61], is shade intolerant [91,174], and is most commonly found on late-seral sites. Forty years following the abandonment of plowed farmland in northeastern Colorado, threadleaf sedge appeared as a minor constituent of a mixed-grass prairie association. The mixed-grass prairie was preceded by a threeawn (Aristida spp.) stage which occurred 20 years after abandonment [36]. Threadleaf sedge is described as a "climax" species on Solonetz soils in western North Dakota [80], in the Theodore Roosevelt National Memorial Park in North Dakota [84], and in the Black Hills of South Dakota [83]. Outside of Davenport, Washington, threadleaf sedge is described as a near "climax" species on mixed grasslands [117]. Threadleaf sedge occurs on "climax" grasslands of the Canadian [37] and Nebraska [171] mixed-grass prairie and on sandy, silty, and limey range sites, and eastern and western sedimentary plains in Montana [148].
In Kimball County, Nebraska, decades of grazing and periodic drought have replaced such mid-grasses as western wheatgrass and needle-and-thread grass with a short-grass disturbance "climax" of buffalo grass, blue grama, and threadleaf sedge [98]
In a remote area of the Little Missouri River Badlands in western North Dakota, 2 mesas which have never been grazed were analyzed. Threadleaf sedge, with a relative cover of 2.34%, is part of the "climax" community on the 2 mesas [140].
In a mixed-grass community in southwestern North Dakota, threadleaf sedge is a dominant species on secondary successional sites. Prior to 1950, threadleaf sedge was a subdominant species on grazed sites, but exclusion of cattle on a portion of the site led to the dominance of threadleaf sedge. The following table illustrates the increase in cover of threadleaf sedge on the secondary successional ungrazed site [18,19]:
Basal cover (%) 1950 1951 1952 1959 1976 1977 Grazed 6.6 11.2 11.9 3.4 9.0 12.8 Ungrazed 23.4 38.5 40.8 33.8 52.0 58.4
Threadleaf sedge forms a dense and tough sod which binds and holds the soil against wind and water erosion [72,147,151,173,175,179]. The roots of threadleaf sedge are able to bind soil years after aboveground vegetation has died [170].
In Yosemite National Park, California, plugs of threadleaf sedge were collected and used to rehabilitate a 4,200 foot (1,280 m) section of denuded trail with partial success. The plugs were collected in the fall of 1991 and planted during the 1992 growing season. In 1995, threadleaf sedge cover was 8% on the rehabilitated site and 24% on surrounding undisturbed control sites [55].
Carex filifolia (lat. Carex filifolia) - cilkimilər fəsiləsinin cil cinsinə aid bitki növü.
Birləpəlilər ilə əlaqədar bu məqalə qaralama halındadır. Məqaləni redaktə edərək Vikipediyanı zənginləşdirin. 
Cil cinsinə aid növlər C. arenaria * C. brevicollis * C. lanceolata * C. michelii * C. klamathensis * C. abrupta * C. acuta * C. acutiformis * C. albida * C. albonigra * C. alma * C. amplifolia * C. angustata * C. appropinquata * C. aquatilis * C. arcta * C. atherodes * C. athrostachya * C. aurea * C. azuayae * C. barbarae * C. buxbaumii * C. canescens * C. capitata * C. cespitosa * C. chordorrhiza * C. comosa * C. concinnoides * C. cusickii * C. depauperata * C. diandra * C. disperma * C. disticha * C. douglasii * C. echinata * C. emoryi * C. ericetorum * C. festucacea * C. filifolia * C. flacca * C. fracta * C. geyeri * C. globularis * C. hassei * C. haydeniana * C. helleri * C. heteroneura * C. hoodii * C. hystericina * C. illota * C. interior * C. intumescens * C. jamesii * C. japonica * C. jonesii * C. lasiocarpa * C. lenticularis * C. lepida * C. leporinella * C. leptalea * C. limosa * C. luzulina * C. lyngbyei * C. mariposana * C. mertensii * C. microptera * C. molesta * C. multicaulis * C. multicostata * C. nebrascensis * C. nervina * C. neurophora * C. nigra * C. nigricans * C. nudata * C. obnupta * C. occidentalis * C. ovalis * C. pachystachya * C. paleacea * C. pansa * C. pauciflora * C. paupercula * C. pellita * C. pendula * C. pensylvanica * C. petasata * C. phaeocephala * C. praeceptorum * C. praegracilis * C. praticola * C. preussii * C. proposita * C. raynoldsii * C. rossii * C. rostrata * C. scoparia * C. secta * C. serotina * C. sheldonii * C. siderosticta * C. siderosticha * C. simulata * C. sodiroi * C. sparganioides * C. specifica * C. spectabilis * C. spissa * C. straminiformis * C. stricta * C. subnigricans * C. tessellata * C. thouarsii * C. toreadora * C. tumulicola * C. umbrosa * C. utriculata * C. vallicola * C. vernacula * C. vesicaria * C. vulpinoidea * C. williamsii Carex filifolia (lat. Carex filifolia) - cilkimilər fəsiləsinin cil cinsinə aid bitki növü.
Carex filifolia is a species of sedge known by the common name threadleaf sedge. It is native to western North America and grows on slopes, eroded areas, gravel, and dry habitats.[1]
Carex filifolia produces clumps of stems which are rounded or triangular, wiry, and angled or curved, reaching up to about 35 centimeters long. The root network is extensive and it forms sod.[2] The leaves are narrow and rolled tightly, appearing quill-like.
The inflorescence is up to 3 centimeters long and has flowers coated with reddish scales. The fruit is covered in a sac called a perigynium which is somewhat hairy. The plant produces some seeds, but mainly reproduces vegetatively.
This sedge is native to much of western North America, from Alaska to California and Manitoba to New Mexico, where it grows in moist and dry habitat.
Carex filifolia is a species of sedge known by the common name threadleaf sedge. It is native to western North America and grows on slopes, eroded areas, gravel, and dry habitats.
Carex filifolia Nutt. es una especie de planta herbácea de la familia de las ciperáceas.
Es nativa de gran parte del oeste de América del Norte, desde Alaska a California y desde Manitoba a Nuevo México, donde crece en hábitat húmedo y seco.
Esta juncia produce racimos de tallos que son redondeados o triangulares, nerviosos, recios, secos, y en ángulo o con curvas, hasta llegar a unos 35 centímetros de largo. La raíz en forma de red es extensa y forma césped.[1] Las hojas son estrechas y figura como una pluma. La inflorescencia es de hasta 3 centímetros de largo y se ha recubierto con flores de color rojizo con escalas. El fruto está cubierto en un saco llamado perigynium que es un poco peludo. La planta se produce por las semillas, pero sobre todo se reproduce vegetativamente.
Carex filifolia fue descrita por Thomas Nuttall y publicado en The Genera of North American Plants 2: 204. 1818.[2]
Carex: nombre genérico que podría derivar del griego kairo, que significa "lastimar", relacionado con las hojas cortantes que poseen estas plantas.[3]
filifolia; epíteto latino que significa "enhebrada como hojas".[4]
Carex filifolia Nutt. es una especie de planta herbácea de la familia de las ciperáceas.
Carex filifolia adalah spesies tumbuhan seperti rumput yang tergolong ke dalam famili Cyperaceae. Spesies ini juga merupakan bagian dari ordo Poales. Spesies Carex filifolia sendiri merupakan bagian dari genus Carex.[1] Nama ilmiah dari spesies ini pertama kali diterbitkan oleh Nutt..
Carex filifolia adalah spesies tumbuhan seperti rumput yang tergolong ke dalam famili Cyperaceae. Spesies ini juga merupakan bagian dari ordo Poales. Spesies Carex filifolia sendiri merupakan bagian dari genus Carex. Nama ilmiah dari spesies ini pertama kali diterbitkan oleh Nutt..
Carex filifolia là một loài thực vật có hoa trong họ Cói. Loài này được Nutt. mô tả khoa học đầu tiên năm 1818.[1]
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Bài viết liên quan đến phân họ cói Cyperoideae này vẫn còn sơ khai. Bạn có thể giúp Wikipedia bằng cách mở rộng nội dung để bài được hoàn chỉnh hơn. Carex filifolia là một loài thực vật có hoa trong họ Cói. Loài này được Nutt. mô tả khoa học đầu tiên năm 1818.
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