BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Rumex acetosella | Sheep Sorrel 



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]

Related categories for Species: Rumex acetosella | Sheep Sorrel