BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Artemisia cana ssp. viscidula | Mountain Silver Sagebrush 



GENERAL BOTANICAL CHARACTERISTICS : 
Mountain silver sagebrush is an erect, freely branching, native,
long-lived, aromatic, deciduous shrub reaching 3.3 feet (1 m) in height
[2].  This subspecies is not as silver in appearance as plains silver
sagebrush.  The leaves of mountain silver sagebrush are smaller, more
narrow, and darker green than those of plains silver sagebrush and are
often crowded in clusters [22].  Although leaf morphology is highly
variable, leaves are generally simple, entire, and tapered at both ends.
On sites where the two occur together, mountain silver sagebrush is
always darker green than mountain big sagebrush [22].  In the Pacific
Northwest, mountain silver sagebrush is morphologically quite similar to
Bolander silver sagebrush (A. cana ssp.  bolanderi), but can be
distingished by darker green leaves [39] and the absence of dense stem
tomentum [29].  Although allelopathy has been documented in plains
silver sagebrush [15], its occurrence in the mountain subspecies has not
been verified.


RAUNKIAER LIFE FORM : 
   Phanerophyte
   Geophyte


REGENERATION PROCESSES : 
Throughout its range, mountain silver sagebrush employs both sexual and
vegetative reproductive strategies.  Within the Artemisia genus, the
silver sagebrush complex is distinguished by its ability to resprout
following disturbance.  Vegetative regeneration is apparently the
primary mode of reproduction.  Mountain silver sagebrush plants are
capable of spreading through rhizomes and root sprouting; they also
readily layer [2,9].  Little regeneration information has been reported
for this subspecies; however, a number of studies have involved plains
silver sagebrush.  See Artemisia cana ssp. cana regeneration slot for
details.


SITE CHARACTERISTICS : 
As the common name implies, mountain silver sagebrush represents the
high elevation form within the silver sagebrush complex.  This
subspecies is typically associated with riparian zones within
nonforested, mountainous communities at elevations above 5,500 feet
(1,677 m) in the Rocky Mountains and above 6,900 feet (2,100 m) in the
Great Basin [15,21,24,39].  Sites include streamsides, meadow margins,
seeps, depressions, and wet mountain slopes.  Mountain silver sagebrush
sites are characterized by seasonally high soil moisture conditions and
are often associated with areas of heavy, lingering snowpack.  Although
generally well-drained, soils become saturated in the spring and early
summer [16], and standing water occassionally accumulates for short
intervals [9].  This subspecies usually occupies deep soils; surface
textures are highly variable.  Soils are often derived from limestone
[29].

Throughout much of its range, mountain silver sagebrush occurs as
stringers along the edges of stream courses, moist meadows, and ponds.
Although silver sagebrush is usually the only component of a low shrub
stratum, sites support an abundant herbaceous understory, and ground
cover is generally high on all but the most severely disturbed sites.
Sites in Oregon are reportedly capable of producing over 2,000 pounds
(909 kg) of dry weight herbage per acre [39].

Elevational ranges for several western states are presented below
[6,18,25,28,33,42]:

        from 7,872 to 9,840 feet (2,400 to 3,000 m) in CO
             6,000 to 8,400 feet (1,830 to 2,561 m) in ID
             greater than 6,000 feet (1,830 m) in MT
             6,500 to 9,000 feet (1,982 to 2,744 m) in WY


SUCCESSIONAL STATUS : 
Mature, self-perpetuating stands of mountain silver sagebrush are
indicative of climax conditions in nonforested communities.  Plants are
established during early seral situations and coexist with later
arriving species.


SEASONAL DEVELOPMENT : 
Detailed information has not been documented concerning the phenological
development of mountain silver sagebrush.  Preliminary data on water
relations in plains silver sagebrush indicate that as plant moisture
stress becomes greater, phenology advances [38].  The following
generalized sequence has been described by Beetle [2] for Wyoming:
        
      Growth initiation               late April to May
      Flowers blooming                August to September
      Seed matures                    October to November

Related categories for Species: Artemisia cana ssp. viscidula | Mountain Silver Sagebrush