BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Oxalis montana | Common Woodsorrel 



GENERAL BOTANICAL CHARACTERISTICS : 
Common woodsorrel is a native woodland perennial with well-developed
clonal growth [1].  It is a small evergreen plant (less than 4 inches
[10 cm] high) that has scaley rhizomes [23].  Common woodsorrel does not
have a main stem.  Leaves, with three cloverlike leaflets, are basal.
The fruit is a round capsule [10,32].


RAUNKIAER LIFE FORM : 
   Geophyte


REGENERATION PROCESSES : 
Reproduction usually involves episodes of seedling recruitment as a
result of disturbance, such as fire and logging, followed by long
periods of vegetative clonal growth [1].  Common woodsorrel forms
extensive colonies in boreal spruce-fir forests; however, its colonies
rarely exceed several feet in diameter in the northern hardwood forests
[35].

Common woodsorrel reproduces both sexually and asexually.  Asexual
flowers (cleistogamous) produce greater amounts of seed compared to
sexual flowers [14].  Total fruit set per plant is low because there is
only one flower per stalk, with a recorded maximum of 34 flowers per
plant [1].  Mature capsules dehisce seeds forcefully, flinging them
outward from the plant [14].


SITE CHARACTERISTICS : 
Common woodsorrel has wide ecologic amplitude and occurs commonly
throughout the northern hardwood and spruce-fir (Picea rubens-Abies
basalmea) forests of the Appalachian Mountains [35].  Some authors have
stated that common woodsorrel occurrence is not correlated with any
particular suite of site features [27,35].

Common woodsorrel is on the glaciated uplands of the Canadian shield
[24].  The shallow soils are sandy loams to loamy tills [20].  Saturated
soils may be poor to moderately well-drained [6,7].  However, soils are
generally poorly developed and often consist only of an organic mat on
top of bedrock [27,31].  Soil pH is strongly to moderately acidic
[15,34,38].  Common woodsorrel occurs on level to steep slopes and any
aspect [5].  Plants occur at 500 feet (152 m) in Maine coastal forests
to 5,000 feet (1,524 m) in the Smoky Mountains of Tennessee [24,34,37].

The growing season throughout its range is from 110 to 140 days and is
cool with ample moisture [8].  Snowpack in the subalpine zones can
extend from November to May [31].  The average annual temperatures are
less than 60 degrees Fahrenheit (16 deg C) [41].  Average annual
precipitation is 90 to 140 inches (2,286-3,556 mm) per year [5].  The
moisture regime is perhumid to humid [31].  Rainfall is equitable in all
summer months.  Fog drip from evergreen needles increases precipitation
amounts [34].

Moss coverage can be low to high, and very high fern coverage reduces
common woodsorrel populations [5].  Associated understory species
include lowbush blueberry (Vaccinium angustifolium), witherod (Viburnum
cassinoides), hobblebush (Viburnum alnifolium), and bunchberry (Cornus
canadensis) [5,8,15].  Overstory species also include white ash
(Fraxinus americana) and paper birch (Betula papyrifera) [31].


SUCCESSIONAL STATUS : 
Obligate Climax Species

Common woodsorrel is a climax understory species.  It is a tolerant
species under mature fir canopy [38,39].  Common woodsorrel is present
in, although not characteristic of, early or mid- seral stages in New
England's northern hardwood or spruce-fir boreal forests [35].
Disturbance occurs as severe winds, hurricanes, and fire [31].


SEASONAL DEVELOPMENT : 
Plant growth mainly occurs before flowers are out [14].  Sexual flowers
on common woodsorrel bloom from late May to August throughout its range
[10,23].  In a population, the flowering period lasts approximately 30
days with individual flowers open for about five days [14].  Fruits
mature in about 12 days, requiring warm days before dehiscence [14].
Seed is shed from June to September throughout its range [14].

Related categories for Species: Oxalis montana | Common Woodsorrel