BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Artemisia frigida | Fringed Sagebrush 



GENERAL BOTANICAL CHARACTERISTICS : 
Fringed sagebrush is a low, mat-forming suffrutescent perennial subshrub
with physiological characteristics typically found in both cool and warm
season plants [4,14,34].  It typically reaches 4 to 16 inches (10-40 cm)
in height and rarely exceeds 24 inches (60 cm) [34,74].  A woody base
gives rise to semiherbaceous annual stems [74].  Leaves are finely
dissected and numerous [21].  Flowers are yellow and discoid [78].  The
gray to brown achenes are flattened with rounded edges [78].

Fringed sagebrush is noted for its relatively deep and extensive root
system.  The composition of the root system is highly variable, which
enables this species to survive on many types of sites.  Well-developed
taproots are produced where deep moisture penetration occurs, but where
surface moisture is greater or where water penetration is prevented by
runoff, no well-developed tap root is formed [19].  A fine network of
fibrous roots, which arises adventitiously from the horizontal stem, is
frequently concentrated near the soil surface [19].  Rooting depths vary
considerably depending on soil type, associated vegetation, and water
availability.  Ecotypic variation may also occur.  Rooting depths of 18
to 65 inches (45-165 cm) have been reported [19].  Rooting is generally
deep and extensive throughout much of the Great Plains, enabling fringed
sagebrush to survive drought periods which commonly occur there [19].
In mountainous regions, the root system tends to be fibrous and
relatively shallow [19].  Even in the same geographic location,
topographic factors may influence rooting depths.  Average maximum
rooting depths within the same soil zones in Saskatchewan ranged from 16
inches (46 cm) on upper slopes to 50 inches (127 cm) on lower slopes
[19].


RAUNKIAER LIFE FORM : 
   Phanerophyte
   Chamaephyte


REGENERATION PROCESSES : 
Fringed sagebrush has tremendous reproductive potential which enables it
to spread, reseed, and invade new sites.  Seeds average over 3,875,000
per pound (8,545/g) and are produced in abundance [46].  Germination of
fresh seed tends to be rather poor, but viability of seed increases with
age up to several years [74].  Large numbers of seeds remain viable in
in the soil for many years until conditions become favorable for
germination [14].

In laboratory tests 50 percent of fringed sagebrush seed germinated
within 5 to 12 days, with most of the remainder germinating slowly
within 30 days [77].  Optimum germination of seed collected in New
Mexico occurred at a constant temperature of 63 degreees Fahrenreit (17
deg C), or for 8-hour periods alternating with 16-hour periods at 56 to
63 degrees Fahrenreit (13.5-17 deg C) [64].  Mean germination time under
these two regimes were 5.4 and 5.3 days respectively [64].  Seed
collected in Montana germinated best at 50 degrees Fahrenreit (10 deg C)
[77].  Temperatures above 93 degrees Fahrenriet (34 deg C) generally
cause a decline in gemination [64].  Germination rates are not
significantly affected by light but are drastically reduced by moisture
stress [64].  Natural spread by seed is described as "good" [58].

Annual seed production appears to be somewhat eratic.  In the prairies
of Saskatchewan and Alberta, fringed sagebrush produces no seed at all
in dry years [17].  Typically less than 50 percent of the plants form
seed even in favorable years.  The light seeds are readily dispersed by
wind.  Dispersal distance of fringed sagebrush seed is reportedly
greater than for many other species of sagebrush [32].

Fringed sagebrush can regenerate vegetatively through rootstock
spreading or stump sprouting [1,13,74].  Adventitous rooting commonly
occurs where stems contact the soil surface [46].  Natural spread
through vegetative means is described as "moderate" [58].  Cuttings
collected from February through May can be propagated vegetatively when
treated with 0.1 percent IBA powder [38].


SITE CHARACTERISTICS : 
Fringed sagebrush is widely distributed over a range of habitats.  It is
common on the high plains along the east slope of the Rocky Mountains,
and in the low semidesert valleys, mesas, foothills, and mountainsides
of the Rocky Mountain and Intermountain regions [74].
 
Fringed sagebrush is best adapted to dry, rocky sites in full sunlight
on porous, coarse, gravelly, sandy, or shallow loam soils [14,74].
Soils may be deep or relatively shallow [38].  Fringed sagebrush is
tolerant of weakly acidic to moderately basic, and weakly saline soils
[77].  Fringed sagebrush favors open, exposed, disturbed sites but is
fairly tolerant of shade and grows in partially shaded woodlands [77].
Elevational ranges are as follows:

        from:  7,500 to 10,000 ft (2,286-3,048 m) in CO
               2,400 to 7,500 ft (731-2,286 m) in MT 
               5,000 to 10,000 ft (1,524-3,048 m) in UT
               3,600 to 10,000 ft (1,097-3,048 m) in WY

Fringed sagebrush grows in a variety of topographic positions including
summit, backslope, footslope, rolling uplands, ridges, upper slopes,
breaks, benches, and bottoms [10,60].  In parts of Alberta and
Saskatchewan, fringed sagebrush appears to grow best on warmer dry,
upper, south-facing slopes [7,20].  Average annual precipitation ranges
from 8 to 12 inches (20-30 cm) or more [38].


SUCCESSIONAL STATUS : 
Fringed sagebrush is well represented in both seral and climax
communities.  In many portions of the Northern Great Plains, it is
subdominant in climax grassland communities [17,72,82].  Francis [28]
reported that it forms topographic climax communities with bluebunch
wheatgrass in portions of the Southwest.  Researchers in British
Columbia noted that fringed sagebrush occurred in both seral and climax
vegetation [56].  Cawker [13] reported that in portions of southern
British Columbia, seral fringed sagebrush communities may be favored by
frequent fire, whereas climax big sagebrush communities are favored by
the absence of fire.

Fringed sagebrush is often described as a pioneer or early seral species
on disturbed sites [39,63,68].  Fringed sagebrush is successionally
"transitional" in the sandhills of southern North Dakota, occurring
after the initial community has established.  Initial community memebers
on the harsh, sandy sites include sand bluestem (Andropogon gerardii
var. paucipilis), prairie dropseed (Sporobolus heterolepis), blowout
grass (Redfieldia flexuosa), sandbur (Cenchrus longispinus), hairy
prairie clover (Petalostemum villosum), sand sunflower (Helianthus
petiolaris), grooved flax (Linum sulcatum), and bugseed (Corispermum
villosum).  These species are extremely tolerant of fluctuating, adverse
environmental conditions.  The transitional fringed sagebrush community
replaces this earliest successional stage.  Vegetation in the
transitional community includes fringed sagebrush, prairie junegrass,
sand dropseed (Sporobolus cryptandrus), Canada wildrye (Elymus
canadensis), heath aster (Aster ericoides), spiderwort (Tradescantia
occidentalis), white sweetclover (Melilotus alba), daisy fleabane
(Erigeron strigosus), and little bluestem.  These plants are
sufficiently tolerant of drought and other environmental extremes to
reproduce under harsh conditions.  Major climax species on these
sandhill sites include big bluestem, prairie sandreed, Leiberg's
panicgrass (Panicum leibergii), and Kentucky bluegrass [9].


SEASONAL DEVELOPMENT : 
In cold-temperate climates fringed sagebrush begins its annual growth in
late winter or early spring [77].  Flowering generally occurs from
summer to late fall [24]:

     beginning of flowering     end of flowering

            June                     October          CO
            July                     October          MT
            July                     September        ND
            July                     September        UT
            May                      September        WY
 
The time of flowering may be influenced by elevation and precipitation
[22,47].  McArthur and Stevens [47] reported flowering in July at higher
elevation sites and as late as November at lower elevations.  Flowering
is typically delayed by dry weather [22].  Seed shatter may occur from
early August [11] through November [49] or December [47].  During a
4-year study in Saskatchewan, fringed sagebrush first flowered from July
23 to August 22, with a mean flowering date of August 8 and latest
flowering date of September 30 [8].  The mean period of flowering was 36
days [8].  Goetz [30] reported average earliest bloom on August 27.

Quiescence generally begins in late October to November or December
[11,49].  A period of fall regrowth may occur during August or September
[49].  However, most annual growth is attained by July or August [30].

Annual phenological variation according to precipitation and temperature
has been widely observed as has general variation by geographic
location.  Listed below are average dates of phenological development
for fringed sagebrush at various locations in Colorado and Canada:

        - northern Colorado [73]

             Quiescence                 November 5-20
             Early growth               April 15-20
             Rapid growth               June 1-10
             Near maturity              August 1-15
        
       - northeastern Colorado [22]

 first visible growth                                      April 1
 first floral buds                                         July
 mature floral buds                                        August
 floral buds and open flowers                              September
 floral buds, open flowers, and ripening fruit             September
 buds, flowers, green and ripe fruit                       October
 buds, flowers, green and ripe fruit and dispersing seed   late October
 green and ripe fruit and dispersing seed                  November
 dispersing seeds and senescence                           November

        Canada - Saskatchewan/Alberta [17]

             renews growth                mid-April
             flower stalks                end of June
             flower buds                  1st week of August
             full bloom                   3rd week of August
             seed ripens, foliage drys 
             soon after                   mid-September

Related categories for Species: Artemisia frigida | Fringed Sagebrush