This description provides characteristics that may be relevant to fire ecology, and is not meant for identification. Keys for identification are available (e.g., [29,30,43,45,49,51]).
Ross'ss sedge is a long-lived, cespitose perennial with dense, medium-sized clumps [20,23,36,39,43,45,47,49,51,62,74]. Where dominant in grassland associations, Ross's sedge can form mats 0.3 to 3 feet (0.1-1 m) across [79]. Culms grow 2 to 15 inches (5-40 cm) tall [36,39,43,45,47,51,62,74,93] with high, slender, erect stems [51,62]. Ross's sedge has several basal leaves, 1 to 4 mm wide and as long as or longer than stems [23,47,49,62,74].
Ross's sedge bears a terminal inflorescence of 1 to 4 apical staminate spikes [47,49,74] 3 to 15 mm long [23,36,93]. Borne near the staminate spikes are 1 to 5 shorter, lateral, few-flowered pistillate spikes 3 to 4.5 mm long [23,36,43,47,49,74,111]. Some plants have shorter culms (0.4-2 inches (1-5 cm)) bearing mostly pistillate spikes, while others have taller culms (2-12 inches (5-30 cm)) bearing both staminate and pistillate spikes [29,30]. Fruit is a 3-sided achene 2 to 5 mm long [47,74].
Ross's sedge is a shallow-rooted (top 2 inches (5 cm) of soil) [35] hemicryptophyte [20]. Most authors agree that Ross's sedge has short, horizontal or ascending stolons or rhizomes [36,39,47,51,74,93]. Others describe Ross's sedge as occurring with and without rhizomes [23,111] or as non-rhizomatous [57,95].
Ross's sedge occurs from Alaska east to Nunavut and south through the western United States to California, Arizona, and New Mexico [23,30,39,41,43,45,47,49,51,52,53,74,84,93,110,111]. It is also common in the Dakotas and Minnesota [29,36,48,52] and occurs rarely in Ontario, Michigan, and Nebraska [36,40,41,52,109].
Flora of North America provides a distributional map of Ross's sedge.
Fire adaptations: Ross's sedge is a residual colonizer after fire [99] and has been described as fire-resistant [47,74,77,108], defined as having a greater than 65% chance that at least half of the population will survive or reestablish after fire [108]. It often increases after fires that do not consume the litter and duff layer or cause excessive soil heating [77,91,96]. Ross's sedge regenerates after fire from surviving rhizomes [15,16,32,77,91,96], approaching preburn coverage within 1 to 2 years [47,74]. Ross's sedge also reestablishes from seed stored in the duff and soil [77,91,96] that is stimulated by soil heating [15,16,32,50,63,91]. Even when Ross's sedge is not present in prefire vegetation, viable seed can remain stored in the soil until fire creates conditions favorable for germination [10].
FIRE REGIMES: Ross's sedge is present in many different plant communities across a large portion of the United States. As a widespread understory species, it is subject to a wide range of FIRE REGIMES, and it is neither eliminated by fire nor dependent on fire. Frequent fires may increase frequency and cover of Ross's sedge due to increased vigor, rhizome extension, and seedling establishment following fire [10,61,108], and by creating openings and reducing shade.
The following table provides fire regime information that may be relevant to Ross's sedge. 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".
Fire regime information on vegetation communities in which Ross's sedge may occur. For each community, fire regime characteristics are taken from the LANDFIRE Rapid Assessment Vegetation Models [59]. These vegetation models were developed by local experts using available literature, local data, and/or expert opinion as documented in the PDF file linked from each Potential Natural Vegetation Group listed below. Cells are blank where information is not available in the Rapid Assessment Vegetation Model. Pacific Northwest California Southwest Great Basin Northern Rockies Northern Great Plains Great Lakes Pacific Northwest Vegetation Community (Potential Natural Vegetation Group) Fire severity* Fire regime characteristics Percent of fires Mean intervalRoss's sedge has high winter hardiness [39] and is found in boreal, temperate, cool semi-arid, and cool mesothermal climates. The occurrence of Ross's sedge increases with increasing continentality and decreases with increasing precipitation [54]. With "very high" drought tolerance [39], Ross's sedge prefers dry sites [39,54,116] and may be considered characteristic of moisture deficient sites [54]. In the Pacific Northwest, Ross's sedge also grows on moist slopes [45,92].
Ross's sedge is common in moist to dry forests [5,43,45,82,110,111], open woods [29,30,41], grasslands [62,79,80], and meadows [14,27,29,30,41,43,45,82,111] in the western portion of its range. It is often found on rocky slopes, unstable screes, and steep banks [39,49,82]. Ross's sedge is common in open woodlands of the northern plains [36], while in Michigan, it grows on sandy or rocky bluffs and windswept crests [40,109].
Ross's sedge prefers well-drained [39,82], moderately dry to very dry, nitrogen-medium soils [54]. Soil textures range from sandy loam to clay loam. Ross's sedge can tolerate excessive soil compaction as well as unstable slopes. Ross's sedge will tolerate mildly saline soils and mildly alkaline to moderately acidic soils [39].
Ross's sedge grows on gentle to steep slopes [22]. The elevational occurrence of Ross's sedge ranges from near sea level to near timberline in the Pacific Northwest [45], and from submontane to subalpine and alpine sites in the Rocky Mountains [54,62,79,80,82,110,111].
Examples of elevation ranges for Ross's sedge by state State Elevation California up to 12,500 feetThe occurrence of Ross's sedge may decrease at higher elevations where snow persists longer into the growing season. A study in a Wyoming subalpine forest (elevation 10,000 feet (3,050 m)) found little or no Ross's sedge on sites where snow persisted past June 27 [55].
Ross's sedge is important summer elk forage, particularly in the first half of the growing season [14,56,65]. Grizzly bears also eat Ross's sedge [25] , and sedges (Carex spp.) are often important winter forage for mountain goats [1].
Palatability/nutritional value: Ross's sedge may be a poor to good forage plant depending on the site [39,62]. Palatability of Ross's sedge has been rated "fair" for domestic sheep, horses, cattle, and small mammals. It has been rated "good" for elk and "poor" for mule deer, white-tailed deer, and pronghorn [28].
In a study of seasonal nutrition trends in Oregon, grasses such as Thurber needlegrass (Achnatherum thurberianum), bottlebrush squirreltail (Elymus elymoides), Sandberg bluegrass (Poa secunda), Idaho fescue (Festuca idahoensis), and prairie Junegrass (Koeleria macrantha) exceed Ross's sedge in protein, phosphorus, calcium, crude fat, and apparent digestibility in early spring. Crude fiber is high in March for Ross's sedge. As the growing season progresses through summer and into fall, Ross's sedge nutritional value increases to surpass the grasses in protein, calcium, crude fat, and apparent digestibility [44]. A Wenatchee National Forest, Washington study found oven-dry crude protein production of Ross's sedge ranged from 0 to 3.9 pounds per acre (4.4 kg/ha). This study also found that crude protein production of Ross's sedge on burned sites was more than double the production on unburned sites [14].
Cover value: Dittberner and Olson [28] rate Ross's sedge cover as poor for large game and fair for nongame birds and small mammals.
Ross's sedge forms dry grassland associations [79] and is a common
aspen parkland [39] and forest understory sedge [47].
Where Ross's sedge dominates the understory, total understory cover may be sparse [3,42].
In north-central Colorado, cover of Ross's sedge is 7% to 16% in ponderosa pine
(Pinus ponderosa)/Ross's sedge habitat types and 4% to 5% in Douglas-fir
(Pseudotsuga menziesii)/Ross's sedge habitat types [42]. Peet [75]
also described limber pine (Pinus flexilis) forests and Rocky Mountain
lodgepole pine (Pinus contorta var. latifolia) forests where
Ross's
sedge is common in the understory, but understory vegetation has little cover.
Vegetation classifications describing plant communities where Ross's sedge is
a dominant species follow:
Ross's sedge productivity increases when ponderosa pine stands are thinned [12].
A study of clearcutting in a Colorado subalpine forest found Ross's sedge present
on sites both before and after logging operations. Data were presented
for sedges in general, and on some sites sedge cover significantly (P=0.05)
increased in the 5 years after logging [24].
Ross's sedge often invades
sites or increases in coverage following mechanical scarification [9,66,77].
However, Ross's sedge may also be susceptible to damage during logging operations
because rhizomes can be displaced by log skidding [35].
Cole's [20] study of trampling and vegetation response
found that Ross's sedge was resistant to trampling, primarily
due to its cespitose growth form. The low matting habit and extensive
root system may allow Ross's sedge to withstand
moderate to severe grazing pressure [39].
Ross's sedge regenerates from seed and rhizomes [39,108].
Pollination: No information is available on this topic.
Breeding system: Ross's sedge is monoecious [23,36,43,47,49,74,111].
Seed production: No information is available on this topic.
Seed dispersal: Ross's sedge has heavy seed [108] with no long-distance seed dispersal [57].
Seed banking: Ross's sedge has soil-stored seed with long-term viability [63,64,95,97,98]. A study of seed banks in Yellowstone National Park found Ross's sedge present in densities greater than 100 seeds/m² [18]. Seed banks studied in central Idaho found Ross's sedge seed stored in soil of 38 out of 48 forested plots. Seeds were found at depths of 0 to 25 inches (0-10 cm) with overall seed viability of 51% [57].
Germination: No information is available on this topic.
Seedling establishment/growth: No information is available on this topic.
Vegetative regeneration: Ross's sedge regenerates from short horizontal or ascending rhizomes following disturbance [39,108]. According to Garrison and Rummell [35], however, the rhizomes are regenerative only when attached to a living plant; once severed they die. According to Steele and Geier-Hayes [95], Ross's sedge is nonrhizomatous, and "sprouts readily following scarification but responds poorly to burning" [95].
Ross's sedge is generally considered an early-seral species on disturbed sites [6,31,57,66,69,79,90,96,114] and has been described as an "aggressive pioneer" [39]. However, Ross's sedge is also found in developed or climax forest communities [2,4,19]. For example, Turner and others [106] described Ross's sedge in a 130 year-old lodgepole pine stand in Yellowstone National Park. A recent study of understory plant species composition in Wyoming found higher cover of Ross's sedge in 30- to 50-year-old clearcut stands than in adjacent mature (>100 years) coniferous forest established after wildfire, supporting descriptions that it is an early to mid-seral species [88].
Ross's sedge is present on sites during the first 10 years following severe fire [97]. It has been described as common following stand-replacing fire in Wyoming lodgepole pine [69] and was found on Douglas-fir and subalpine fir habitat types in Yellowstone in the first 5 years after fire [6]. Its presence in early successional vegetation after fire is due to regeneration from surviving rhizomes and soil-stored seed [15,16,32,77,91,96]. For more information, see Fire Adaptations. Ross's sedge often dominates the forb layer of early-successional forest vegetation [57] and is found in open forest stands [39,62]. Though Ross's sedge may occasionally occur on forest sites with moderate to heavy shade, it is generally shade intolerant [54,57], becoming less important and eventually eliminated as it is overtopped by taller plants [57]. Ross's sedge forms a dry grassland association in clearcuts or burned areas of montane and subalpine coniferous forests in Colorado. These early-seral communities eventually give way to reestablished canopy species (e.g., limber pine, lodgepole pine). Shade from the closing canopy reduces Ross's sedge abundance. If the forest is slow to develop, however, Ross's sedge grasslands may persist for decades or centuries [79].
Ross's sedge has been rated as "highly persistent" when used for reclamation. The extensive root system and ability to establish and persist on unstable as well as compacted soils make Ross's sedge an excellent soil builder with good erosion control capability [39]. Ross's sedge may establish from either transplants or seed. An Oregon study of campsite rehabilitation found that Ross's sedge had 100% transplant survival over 7 years, and transplants increased substantially in both height and area [21]. Following a road-building project, Ross's sedge dominated unseeded disturbed areas [64].
A greenhouse study found a greater number of Ross's sedge seedlings emerged from heated soil samples than from unheated soil samples [100].
Carex rossii, commonly known as Ross's sedge, is a hardy species of sedge that is often a pioneer species in areas with little or no established vegetation, or in places where disturbance has occurred. Ross's sedge grows in a variety of habitats throughout much of western North America, from Alaska to Ontario, south to New Mexico and California. It flowers in May and June.[3][4][5]
Carex rossii was first described by Francis Boott in Hooker's Flora Boreali-Americana (1839). The type locality was listed as "Hab. N. W. Coast. Douglas. Rocky Mountains. Drummond" (sic)".[6]
Carex rossii produces a dense clump, or solid mat of slender stems up to about 40 centimetres (16 in) from a shallow network of rhizomes. The pale to dark green leaves are usually longer than the stems. The inflorescences contain one or more staminate flower spikes above more rounded pistillate spikes. The fruit is three-sided, and covered in a greenish or brownish perigynium.[3][4]
Carex rossii is native to, and sometimes abundant in, Alaska and subarctic Canada (Nunavut, Northwest Territories, and Yukon Territory); western Canada (Alberta, British Columbia, Manitoba, and Saskatchewan); and the contiguous U.S. (Arizona, California, Colorado, the Dakotas, Idaho, Minnesota, Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming.) It is found only sporadically in Ontario, Michigan, and Nebraska.[2][3][7]
It grows in many habitat types, including wet and dry areas in forest, sagebrush, prairie, and alpine meadows.[3][4][8]
Carex rossii, commonly known as Ross's sedge, is a hardy species of sedge that is often a pioneer species in areas with little or no established vegetation, or in places where disturbance has occurred. Ross's sedge grows in a variety of habitats throughout much of western North America, from Alaska to Ontario, south to New Mexico and California. It flowers in May and June.
