Index of Species Information

SPECIES:  Rumex acetosella


SPECIES: Rumex acetosella
AUTHORSHIP AND CITATION : Esser, Lora L. 1995. Rumex acetosella. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: [].

ABBREVIATION : RUMACE SYNONYMS : NO-ENTRY SCS PLANT CODE : RUAC3 COMMON NAMES : sheep sorrel common sheep sorrel red sorrel TAXONOMY : The currently accepted scientific name of sheep sorrel is Rumex acetosella L. [29,34,51,95]. It is in the family Polygonaceae. There are no recognized infrataxa [34,44]. LIFE FORM : Forb FEDERAL LEGAL STATUS : No special status OTHER STATUS : NO-ENTRY


SPECIES: Rumex acetosella
GENERAL DISTRIBUTION : Sheep sorrel is a forb of Eurasian origin that has naturalized throughout temperate North America with the possible exceptions of Louisiana, Mississippi, and Alabama, and the northern Canadian provinces [46,75,95]. ECOSYSTEMS :    Sheep sorrel is found in nearly all FRES ecosystems. STATES :      AK  AZ  AR  CA  CO  CT  DE  FL  GA  HI      ID  IL  IN  IA  KS  KY  ME  MD  MA  MI      MN  MO  MT  NE  NV  NH  NJ  NM  NY  NC      ND  OH  OK  OR  PA  RI  SC  SD  TN  TX      UT  VT  VA  WA  WV  WI  WY  AB  BC  MB      NB  NS  ON  PQ  SK BLM PHYSIOGRAPHIC REGIONS :     1  Northern Pacific Border     2  Cascade Mountains     3  Southern Pacific Border     4  Sierra Mountains     5  Columbia Plateau     6  Upper Basin and Range     8  Northern Rocky Mountains     9  Middle Rocky Mountains    10  Wyoming Basin    11  Southern Rocky Mountains    12  Colorado Plateau    13  Rocky Mountain Piedmont    14  Great Plains    15  Black Hills Uplift    16  Upper Missouri Basin and Broken Lands KUCHLER PLANT ASSOCIATIONS : NO-ENTRY SAF COVER TYPES :    Sheep sorrel is found in nearly all SAF Cover Types.  SRM (RANGELAND) COVER TYPES :    101  Bluebunch wheatgrass    102  Idaho fescue    103  Green fescue    108  Alpine Idaho fescue    110  Ponderosa pine-grassland    201  Blue oak woodland    203  Riparian woodland    204  North coastal shrub    215  Valley grassland    216  Montane meadows    304  Idaho fescue-bluebunch wheatgrass    409  Tall forb    411  Aspen woodland    601  Bluestem prairie    804  Tall fescue    809  Mixed hardwood and pine HABITAT TYPES AND PLANT COMMUNITIES : Sheep sorrel occurs mainly in grassland, mixed-grass prairie, and montane meadow communities of western North America, but is also common in forested communities throughout temperate North America.  Sheep sorrel is common in floodplain and riparian habitats.  In western Washington sheep sorrel is found on gravel bars and floodplains dominated by Scouler willow (Salix scouleriana).  Other associates include Virginia strawberry (Fragaria virginiana), velvetgrass (Holcus lanatus), white clover (Trifolium repens), curly dock (Rumex crispus), and bog rush (Juncus effusus) [20].  In Oregon sheep sorrel occurs in a riparian mountain meadow community dominated by cheatgrass (Bromus tectorum) [45].  In California sheep sorrel occurs in a freshwater marsh community dominated by tall fescue (Festuca arundinacea), sedge (Carex spp.), and narrow-leaved cattail (Typha angustifolia) [18]. Sheep sorrel is commonly found in old fields, annual grassland, and montane meadow communities.  In Connecticut sheep sorrel occurs in a postagricultural little bluestem (Schizachyrium scoparium) grassland. Associates include redtop (Agrostis alba) and yellow sedge (Carex pensylvanica) [69].  In New Jersey sheep sorrel is a member of an old-field plant community dominated by Canada goldenrod (Solidago canadensis) [9].  Sheep sorrel is commonly found in southern Appalachian grassy bald communities dominated by mountain oatgrass (Danthonia compressa).  Other associates include thornless blackberry (Rubus canadensis), hillside blueberry (Vaccinium pallidum), and violet (Viola spp.) [56,60].  In Indiana sheep sorrel occurs in a little bluestem community with hackberry (Celtis occidentalis) and smooth horsetail (Equisetum laevigatum) [81].  In Montana sheep sorrel occurs in mixed-grass prairie communities [86]. In California sheep sorrel is common in annual grassland, montane meadow, and perennial bunchgrass communities.  Associates include ripgut brome (Bromus rigidus), soft chess (B. hordeaceus), silver hairgrass (Aira caryophyllea), Kentucky bluegrass (Poa pratense), Sandberg bluegrass (P. nevadensis), Italian thistle (Carduus pycnocephalus), wild oat (Avena fatua), and Italian ryegrass (Lolium multiflorum) [8,12,18,61].  At Point Reyes National Seashore, California, sheep sorrel occurs in a coastal grassland community with coast rock cress (Arabis blepharophylla), poison-oak (Toxicodendron diversiloba), California barberry (Berberis pinnata), and the endangered Sonoma spineflower (Chorizanthe valida) [11,12]. Sheep sorrel is a common understory species in forested habitats throughout North America.  In Pennsylvania sheep sorrel occurs in eastern white pine (Pinus strobus)-poverty oatgrass (D. spicata) communities; associates include Canada goldenrod, fireweed (Epilobium angustifolium), whorled yellow loosestrife (Lysimachia quadrifolia), Virginia springbeauty (Claytonia virginica), trout lily (Erythronium americanum), mountain wood sorrel (Oxalis montana), and violet [3,49,93].  In Alberta sheep sorrel is a member of an 80-year-old white spruce (Picea glauca)-jack pine (Pinus banksiana)-feathermoss (Pleurozium spp.)  community [21].  In Idaho sheep sorrel occurs in grand fir (Abies grandis)/wild ginger (Asarum caudatum), grand fir/pachistima (Pachistima myrsinites), and grand fir/ninebark (Physocarpus malvaceus) habitat types [30,53,54,99].  In California sheep sorrel occurs in redwood (Sequoia sempervirens), Douglas-fir (Pseudotsuga menziesii), and Oregon white oak (Quercus garryana) habitats [22,50,83]. In Montana and Wyoming, sheep sorrel is found in alpine tundra environments [94]. 


SPECIES: Rumex acetosella
IMPORTANCE TO LIVESTOCK AND WILDLIFE : In Arizona sheep sorrel is grazed by cattle and sheep, but has little forage value [39].  Sheep sorrel contains oxalic acid which can be poisonous [46,100]. In California and Ohio sheep sorrel is grazed by mule deer [50,70].  In Idaho, Montana, and Wisconsin sharp-tailed grouse and ruffed grouse eat sheep sorrel seed [40,41,76,86].  PALATABILITY : In Utah palatability ratings for sheep sorrel are fair for cattle and poor for sheep and horses [100].  NUTRITIONAL VALUE : Sheep sorrel nutritional levels are adequate to meet the requirements of mule deer [50].  Energy and protein content ratings of sheep sorrel are poor.  Nutritional values are rated as poor for waterfowl and fair for elk, mule deer, upland game birds, small nongame birds, and small mammals [100]. COVER VALUE : In Utah sheep sorrel cover values are rated as fair for small mammals and small nongame birds and poor for upland game birds and waterfowl [100].  VALUE FOR REHABILITATION OF DISTURBED SITES : Sheep sorrel colonizes disturbed sites such as clearcuts, streambanks, and surface mined lands.  It has been used for revegetation of disturbed lands, although it is rated low for erosion control, and short- and long-term revegetation potential [100].  In a mining and smelting region of Sudbury, Ontario, sheep sorrel established when a thin sprinkling of limestone was applied to the soil [97]. In east-central Texas revegetation of eight unreclaimed mine sites occurred naturally.  These sites and an adjacent unmined site were sampled to determine vegetational changes over time.  The percent frequency of sheep sorrel was as follows [79]:     3m*    6m    5y    10y    15y    20y    30y    50y    control         0     11     4      6      4      3      0      0       0 *m=months since first sampling, y=years since first sampling In Pennsylvania an attempt was made to transplant rootstocks of sheep sorrel on black waste sites created by anthracite mining.  All emergent vegetation was subsequently heat killed [77]. OTHER USES AND VALUES : Sheep sorrel leaves are used in salads [4,51].  The Nuxalk Indians of British Columbia eat sheep sorrel [55].  OTHER MANAGEMENT CONSIDERATIONS : Sheep sorrel is classified as a noxious weed in 23 states [67].  It is a serious weed in pastures and rangelands.  Control is difficult because of its perennial, creeping rhizomes [4,52].  Sheep sorrel is a common weed in West Virginia, except in limestone regions; liming the soil may help eradicate sheep sorrel [82].  Sheep sorrel presence and abundance are indicative of poor and "sour" soils [82,87].  It reaches peak abundance at low soil nitrogen levels [87].  Sheep sorrel is potentially poisonous to livestock because of the presence of soluble oxalates [19]; however, it is grazed by sheep and cattle [39].  In Idaho sheep sorrel is an increaser species under heavy grazing regimes, and a decreaser species under light grazing regimes [54].  In Oregon percent frequency of sheep sorrel was not affected by late season cattle grazing in a riparian mountain meadow [45]. In Novia Scotia sheep sorrel is one of the most common weed species in lowbush blueberry fields.  Control with hexazinone was attempted but after the activity of the herbicide decreased, sheep sorrel grew and produced a large number of seeds [62].  In Pennsylvania in a goldenrod (Solidago spp.)-aster (Aster spp.) community, sheep sorrel was dominant in 1- and 3-year-old plowed, disked, prometone-treated plots [64].  Control Methods:  Repeat cultivation during dry weather gradually weakens rootstalks of sheep sorrel [19].  According to Fitzsimmons [19] several herbicides can selectively control sheep sorrel.  


SPECIES: Rumex acetosella
GENERAL BOTANICAL CHARACTERISTICS : Sheep sorrel is an introduced rhizomatous perennial herb that sometimes forms dense colonies by adventitious shoots from widely spreading roots and rhizomes [19,29,35,52,92].  Stems are erect, slender, and 4 to 24 inches (10-60 cm) tall [33,72,95].  Leaves are 0.8 to 4 inches (2-10 cm) long and 0.4 to 0.8 inch (1-2 cm) wide [33,34,72].  The fruit is an achene [25,29,38,72,95].  Roots are slender, almost fibrous and penetrate to a depth of 5 feet (1.5 m) [48]. RAUNKIAER LIFE FORM :    Hemicryptophyte    Geophyte REGENERATION PROCESSES : Sexual:  Sheep sorrel reproduces by seed.  It is wind pollinated and seed is dispersed by wind and insects [37,91].  Sheep sorrel regularly colonizes from buried seed following disturbance [14,21,26].  In Massachusetts sheep sorrel was not present in the ground cover of most eastern white pine and red pine (Pinus resinosa) stands, but seeds were contained in soil samples from 1-to 80-year-old stands.  In the laboratory soil-stored seeds from all stands germinated [57]. Vegetative:  Sheep sorrel reproduces from creeping roots and rhizomes [2,16,48,77].  Shoots develop from stem buds that arise adventitiously at irregular intervals on horizontal roots.  Adventitious buds are usually found in the top 8 inches (20 cm) of soil [48].  SITE CHARACTERISTICS : Sheep sorrel is common in fields, pastures, meadows, waste places, and along roadsides [4,29,39,46,72,95].  In Olympic National Park, Washington, sheep sorrel is commonly found on lower terraces and gravel bars of the riparian zone [1,13,63].  Sheep sorrel is generally found in open, unshaded areas on disturbed sites [29,92,95].  It thrives on acidic soils with low fertility, but is adapted to a variety of soil types [19,29,96].  Sheep sorrel is commonly found on sandy loam, fine sandy, silty, and gravelly soils [6,7,14,58,99].  Elevations for sheep sorrel are as follows:                     feet            meters           Arizona          5,500-8,000     1,650-2,400     [46] California           0-9,900         0-3,000     [34] Colorado        4,000-11,200     1,200-3,360     [33,100] Connecticut      1,020-1,050         310-320     [14] Idaho            2,800-6,000       853-1,830     [65,99] Montana          3,300-6,200       990-1,860     [100] New York           900-1,700         270-510     [85] Oregon                <4,000          <1,200     [66] Utah             4,500-9,100     1,350-2,730     [95,100] Washington            <4,000          <1,200     [66] Wyoming          6,000-9,000     1,800-2,700     [100] SUCCESSIONAL STATUS : Sheep sorrel invades disturbed sites and may move onto undisturbed sites when growing conditions are ideal [1,16,52,77].  It is commonly found on clearcut, burned, and flood-disturbed riparian sites [1,13,27,94].  It colonizes rapidly by seed and may persist for 15 to 20 years through vegetative growth and propagation [16].  Competition from other species on good soils may reduce its abundance [19]. In South Carolina sheep sorrel is found in the early seral stages of a disturbed old-field broomsedge bluestem (Andropogon virginicus) community [101].  In the Pacific Northwest sheep sorrel seed generally remains viable in the soil long enough to provide a source of new infestations when the soil is disturbed [19].  In Massachusetts buried sheep sorrel seed germinated from soil samples from eastern white pine and red pine stands 1 to 80 years old [57].  Sheep sorrel is moderately shade tolerant.  In the foothills of the Sierra Nevada and Coast Ranges, California, sheep sorrel was more abundant under dead blue oak (Quercus douglasii) trees (5.7%) than in open grassland (5.2%) or live blue oak stands (<0.1%) [36]. SEASONAL DEVELOPMENT : Sheep sorrel flowering dates are as follows: California         Mar-Aug      [68] Idaho              May-Sept     [19] Georgia            Mar-Jun      [98] Kansas             Apr-July     [4] Montana            May-Aug      [100] North Carolina     Mar-July     [72,98] North Dakota       May-Jun      [100] Oregon             May-Sept     [19] South Carolina     Mar-July     [72,98] Tennessee          Mar-Jun      [98] Virginia           Mar-Jun      [98] Washington         May-Sept     [19] West Virginia      May-Sept     [82] Great Plains       Apr-Aug      [29]


SPECIES: Rumex acetosella
FIRE ECOLOGY OR ADAPTATIONS : Sheep sorrel probably survives fire by sprouting from rhizomes and roots [47,72].  It probably regenerates from on-site buried seed.  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 :    Rhizomatous herb, rhizome in soil    Ground residual colonizer (on-site, initial community)    Secondary colonizer - off-site seed


SPECIES: Rumex acetosella
IMMEDIATE FIRE EFFECT ON PLANT : Sheep sorrel is probably top-killed by fire. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY PLANT RESPONSE TO FIRE : Sheep sorrel probably sprouts from rhizomes following fire and establishes from on-site seed [14,21,26].  Several studies describe establishment or increase of sheep sorrel after fire.  Very severe fire may kill sheep sorrel. In New Brunswick a woodlot was clearcut in the fall of 1949 and prescribed burned in April 1951.  The number of stems of sheep sorrel per area present in June 1949, 1950, 1951, and 1952 were 0, 0, 18, and 28, respectively [31].  In New Brunswick understory layers of 11 mixed hardwood stands representing an age sequence of 7 to 57 postfire years were examined.  Sampling occurred in July and August 1973 and 1974. Sheep sorrel was found in stands 7, 10, 13, 17, and 25 years old.  It did not occur in some 7-year-old stands, or in stands 18, 20, 29, and 37 years old [58]. In Idaho seral brushfields in a grand fir/pachistima habitat type were prescribed burned on May 14, 1975, and a portion was seeded on May 15, 1975.  Sheep sorrel was present on the burn-only area, but did not occur on the burn-and-seed site.  Frequency (out of 10 possible plots) of sheep sorrel was as follows [53]:                     Prefire          Postfire year                     July 3, 1974        1    2    4 control                1              2    3    3 burn only              0              0    5    4 burn and seed          0              0    0    0   In Idaho a wildfire burned a ponderosa pine (Pinus ponderosa) forest and adjacent montane grassland on August 10, 1973 for 43 days.  Fourteen sites were examined in June 1974 and June 1976.  Percent cover and frequency of sheep sorrel on burned and unburned sites were as follows [65]:                             1974                     1976                      burned     unburned      burned      unburned cover +/- SD        t* +/- 1    t +/- t      2 +/- 3      1 +/- 2 frequency +/- SD    1  +/- t    t +/- 1      2 +/- 4      1 +/- 2 *t = trace In Washington on the Mount Adams huckleberry (Vaccinium spp.)  fields, an experimental area was prescribed burned from October 3-7, 1972. Average understory cover (%) of sheep sorrel from 1972 to 1977 was as follows [66]:                1972 (before treatment)    1973    1974    1975    1977 unburned, uncut      0.2                   0.2     0.3     0.3     0.2 thin, underburn      0.2                   0.6     0.9     1.2     1.5 clearcut and burn    0.2                   0.9     1.9     1.0     1.6 In Great Britain severe fires in late summer 1976 killed all surface vegetation.  Sheep sorrel first appeared in burned areas in October 1985, postfire year 9 [59].  DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : Some research describes no change in cover or frequency in sheep sorrel after fire.  In California the effects of a late fall burn on a mountain meadow in Grover Hot Springs State Park were evaluated.  Both wet and dry meadow plots were prescribed burned by a low- to moderate-intensity fire in mid-November 1987.  Sheep sorrel was found only on dry plots before burning and did not increase following fire [8]. In Connecticut experimental tracts were set up in a little bluestem grassland in 1967.  Tract A was prescribed burned annually from 1968-1976, and in 1978, 1980, 1983, and 1985.  Tract B was prescribed burned annually from 1968-1975, and in 1978, 1980, 1983, and 1985. Sheep sorrel percent cover and frequency in two burns and 2 control plots on each tract were as follows [69]:                      Tract A                        Tract B                1967           1985            1967           1985             cover  freq    cover  freq     cover  freq    cover   freq treatment Burn         <1     9        2     6        <1     29      <1      5    Control      <1     22       0     0         1     65      <1      27      The following Research Project Summaries provide information on prescribed fire use and postfire response of plant community species, including sheep sorrel, that was not available when this review was originally written: FIRE MANAGEMENT CONSIDERATIONS : NO-ENTRY


SPECIES: Rumex acetosella
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