Index of Species Information

SPECIES:  Hesperostipa spartea


SPECIES: Hesperostipa spartea
AUTHORSHIP AND CITATION : Walkup, Crystal J. 1991. Hesperostipa spartea. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: [].

ABBREVIATION : HESSPA SYNONYMS : Stipa spartea Trin.[22,23] Stipa robusta Nutt. ex Trin. SCS PLANT CODE : STSP2 COMMON NAMES : porcupine grass big needlegrass short-awn porcupine grass western porcupine grass TAXONOMY : The currently accepted scientific name for porcupine grass is Hesperostipa spartea (Trin.) Barkworth (Poaceae)[54]. LIFE FORM : Graminoid FEDERAL LEGAL STATUS : No special status OTHER STATUS : Porcupine grass is considered rare in Ontario.


SPECIES: Hesperostipa spartea
GENERAL DISTRIBUTION : Porcupine grass is found from British Columbia to Ontario, south through Montana, Wyoming, Colorado, and New Mexico, and east through most of the central states to Pennsylvania. Western porcupine grass (S. s. var. curtiseta) is found in Manitoba, Alberta, Montana, South Dakota, and Wyoming. ECOSYSTEMS : FRES15 Oak - hickory FRES21 Ponderosa pine FRES29 Sagebrush FRES36 Mountain meadows FRES38 Plains grasslands FRES39 Prairie STATES : AZ CO IL IN IA KS MN MO MT MI MN NM OH OK PA SD TX WI WY AB BC MB NB ON SK BLM PHYSIOGRAPHIC REGIONS : 10 Wyoming Basin 12 Colorado Plateau 13 Rocky Mountain Piedmont 14 Great Plains 15 Black Hills Uplift 16 Upper Missouri Basin and Broken Lands KUCHLER PLANT ASSOCIATIONS : K016 Eastern ponderosa forest K056 Wheatgrass - needlegrass shrubsteppe K063 Foothills prairie K064 Grama - needlegrass - wheatgrass K066 Wheatgrass - needlegrass K067 Wheatgrass - bluestem - needlegrass K068 Wheatgrass - grama - buffalograss K069 Bluestem - grama prairie K074 Bluestem prairie K081 Oak savanna SAF COVER TYPES : 14 Northern pin oak 42 Bur oak 110 Black oak 236 Bur oak 237 Interior ponderosa pine SRM (RANGELAND) COVER TYPES : NO-ENTRY HABITAT TYPES AND PLANT COMMUNITIES : Western porcupine grass is codominant with rough fescue in an upland grassland in central Alberta [3]. In Indiana, porcupine grass and little bluestem (Schizachyrium scoparium) are major components in dry sand prairies and black oak (Quercus velutinus) savannahs [6]. In Wisconsin, South Dakota, and Nebraska, it is codominant with little bluestem [8,28,45]. Porcupine grass occurs as a dominant or subdominant in the following community type (cts) classifications: Area Classification Authority sw ND grassland cts Whitman 1979 sc ND: Central Grasslands grassland cts Lura and others 1988 Research Station ND: Woodworth Station general veg. cts Meyer 1985 Alberta: Peace - Athabasca general veg. cts Dirschl and others Delta 1974


SPECIES: Hesperostipa spartea
IMPORTANCE TO LIVESTOCK AND WILDLIFE : Porcupine grass is an important early season forage of good but not choice palatability for all classes of livestock. As the species matures the leaves become somewhat tough for sheep but are still grazed to some extent. The value of porcupine grass as forage is relatively higher in the fall than in midsummer because it remains green after most grasses have dried [24]. PALATABILITY : Palatability varies with phenological development. Palatability is highest in the spring and early summer when plants are young and succulent. Porcupine grass remains moderately palatable until the seedheads mature, at which time long, sharp awns may injure grazing livestock and render the plant less palatable [18,40]. The relish and degree of use shown by livestock and wildlife species for porcupine grass in Montana and North Dakota has been rated as follows [12]: MT ND Cattle Fair Fair Sheep Fair Poor Horses Fair Fair Pronghorn ---- Poor Mule deer ---- Poor White-tailed deer ---- Poor Small nongame birds ---- Poor Upland game birds ---- Good NUTRITIONAL VALUE : The nutritional value of porcupine grass during five major stages of growth are [26] (values are percentage of dry weight with the exception of carotene which is in mg/kg): Leaf Stage Heading Seed-ripe Cured Weathered Dry Matter 94.0 92.0 92.0 94.0 94.0 Protein 9.1 6.2 7.3 4.3 4.5 Crude Fat 3.4 3.2 4.2 4.3 3.5 Crude Fiber 28.0 34.0 29.0 31.0 32.0 Ash 7.0 5.6 6.6 8.2 8.0 Calcium 0.3 0.3 0.3 0.4 0.4 Phosphorus 0.1 0.1 0.1 0.1 0.1 Carotene 20.0 24.0 67.0 6.9 2.9 COVER VALUE : The degree to which porcupine grass provides environmental protection during one or more seasons for wildlife species has been rated as follows [12]: ND Pronghorn Good Mule deer Good White-tailed deer Fair Small nongame birds Good Upland game birds Good Waterfowl Fair VALUE FOR REHABILITATION OF DISTURBED SITES : Trail restoration was conducted in Saskatoon, Saskatchewan, on old trails found on a steep (2:1), sandy, south-facing slope. Seeds found in prairie hay mulch (primarily needle-and-thread grass (Hesperostipa comata) and porcupine grass) held down by jute mesh blankets successfully germinated and established new growth [10]. Porcupine grass is difficult to establish by seed. Germination varies from 0 to 12 percent [21], and seeds are extremely difficult to clean, which reduces purity. Transplanting has been fairly successful but is very costly [37,41]. Porcupine grass mulch seems to be the best choice for successful, low-cost establishment. OTHER USES AND VALUES : Native Americans of the Missouri River Region used the stiff awns to make hair brushes [17]. OTHER MANAGEMENT CONSIDERATIONS : Porcupine grass decreases with overgrazing. Moderate to severe grazing pressure greatly reduces later growth and seed production [14,49]. Slight to light use removes standing litter, increasing growth of porcupine grass [44]. Frequent early mowing (June or July) results in a decrease in cover of porcupine grass, whereas delaying mowing until August may increase its cover [8,9]. Porcupine grass does poorly under drought conditions but is able to recover once conditions have returned to normal. Seedling survival during simulated drought conditions ranged from 0 to 54 percent [36]. Porcupine grass was listed among species which had high mortality during the 30's drought. Mortality was thought to result from the relatively shorter roots on these grasses. However, once drought conditions ended, porcupine grass regained its original territory and spread widely [48].


SPECIES: Hesperostipa spartea
GENERAL BOTANICAL CHARACTERISTICS : Porcupine grass is a native, perennial, cool-season bunchgrass. It is often confused with needle-and-thread grass, but its leaves are longer, generally less rolled, lighter in color, and considerably wider [18]. It may grow to a height of 4 feet (1.2 m) but generally reaches 1.5 to 3 feet (0.45-0.9 m). Flower stalks grow from 2 to 4 feet (0.6-1.2 m). Root systems of mature plants usually reach depths of about 4.5 feet (1.35 m), but occasionally extend to 6 feet (1.8 m). Numerous, profusely branched, smaller roots occupy the top 8 to 18 inches (20-46 cm) of soil, spreading horizontally or diagonally downward. The longer roots give rise to many laterals which divide into fine branches in deeper soil [47]. RAUNKIAER LIFE FORM : Undisturbed State: Cryptophyte (geophyte) Burned or Clipped State: Cryptophyte (geophyte) REGENERATION PROCESSES : Porcupine grass reproduces sexually [12]. The seeds have a unique method of planting themselves. As the twisted awns expand and contract with variations in temperature and moisture, the seeds are drilled into the soil. Strong winds may transport seeds a considerable distance, especially when awns are twisted together in clumps [42]. Animals also carry seeds as the awns become trapped in their coats. SITE CHARACTERISTICS : Porcupine grass is found in prairies, foothills, and canyons at lower elevations, often dominating dry, well-drained sites [14,45]. In Colorado it is found from 5,300 to 7,500 feet (1,615 to 2,286 m) in dry to moist habitats [12]. In Minnesota it is dominant on a sandy level upland. It also occurs on well-drained gentle slopes but is not dominant [13]. In Nebraska it is found on high prairie, low prairie, and disturbed areas, but is typically an upland species, generally dominant on south and east slopes [8,42]. It mainly occurs on poorer soil types throughout the northern Great Plains [40]. SUCCESSIONAL STATUS : Porcupine grass is a climax dominant on several sites in the Great Plains [8,28,45]. It also occurs as a pioneer species, often establishing on small disturbed or denuded areas, such as gopher mounds [42]. SEASONAL DEVELOPMENT : Leaf growth of porcupine grass begins in late March to early April in western North Dakota [18]. Flowering occurs earliest in the eastern and southern, and latest in the northern and western portion of its range [33]. In Wyoming, North Dakota, and Nebraska flowering occurs from May to June [12,42], and in Montana from June to August [12]. A study in western North Dakota recorded an 8-year average of the significant phenological stages of porcupine grass [18]. Initiation of Head Seed Seed Leaves Fruiting Stalk Emergence Anthesis Maturity Shatter 50-75% Dry June 2 June 14 June 28 June 27 July 9 August 28


SPECIES: Hesperostipa spartea
FIRE ECOLOGY OR ADAPTATIONS : Porcupine grass survives low to moderate severity fires due to carbohydrate reserves stored in an underground root crown. It lacks rhizomes, and the root system is relatively shallow. Severe fires can kill the root crown, but such fires are rare on grasslands [48]. Fire was an important ecological factor on prairies containing porcupine grass. In the absence of fire, tree encroachment was common, and the plant community often changed to forest within 30 years [3,50]. FIRE REGIMES : 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". POSTFIRE REGENERATION STRATEGY : survivor species; on-site surviving root crown off-site colonizer; seed carried by animals or wind; postfire yr 1&2


SPECIES: Hesperostipa spartea
IMMEDIATE FIRE EFFECT ON PLANT : All aboveground portions of porcupine grass are destroyed by fire. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY PLANT RESPONSE TO FIRE : Kruse and Higgins [29] reported porcupine grass both increasing and decreasing following spring burns. Four studies reported favorable responses after spring burns which occurred from April 30 to May 26 [3,7,27,38], while four reported neutral or negative responses after burning between April 9 and May 8 [2,20,25,52]. Positive effects include increased seed production and flowering [3,38], an increase in total biomass [7], and an increase in cover [27]. Negative effects include a decrease in cover [2,25] and a reduction in culm production [20]. Porcupine grass was listed as actively growing in one study [25], and growing season precipitation was lower than normal in another study [20], which may account for the negative responses. The majority of the studies provided insufficient information for direct comparison of the effects of burning in different seasons. A general statement about cool-season grasses is that they are harmed by late spring burns when actively growing. The four studies which gave results contradicting this did not report the phenological stage of porcupine grass prior to burning. DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : Twenty-five years of annual burning decreased cover of western porcupine grass in east-central Alberta. No season or intensity of fire was given [1]. Annual spring burns (late April to early May) in two Minnesota studies favored porcupine grass [43,50]. Burning was conducted to return the area to pre-settlement oak savannah woodlands [50], and to determine the effects of fire on an aspen-prairie ecotone [43]. Fall burning (October 3) reduced canopy coverage and seed production. The growth stage was not determined prior to the fire [3]. The Research Project Summary Seasonal fires in Saskatchewan rough fescue prairie provides information on prescribed fire use and postfire response of plains grassland community species, including porcupine grass, that was not available when this species review was originally written. FIRE MANAGEMENT CONSIDERATIONS : Due to the varied results under similar burning conditions, it is difficult to make accurate management recommendations.

References for species: Hesperostipa spartea

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