BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Salix boothii | Booth Willow 



GENERAL BOTANICAL CHARACTERISTICS : 
Booth willow is a native, multibranched, rounded shrub typically between
9 and 18 feet (3 and 6 m) tall [1,34].  On well-drained soils in Oregon,
Booth willow is broadly rounded and has many stems, but in bogs it is
dwarfed and has few stems [20].  At 10 years of age, Booth willow
reaches a height of approximately 8 feet (2.5 m).  Stems reach
senescence between the ages of 15 and 20 years [20].  Male and female
flowers occur on separate plants in 0.5- to 1.5-inch-long (1-1.5 cm),
erect catkins [12].
  


RAUNKIAER LIFE FORM : 
   Phanerophyte


REGENERATION PROCESSES : 
Sexual reproduction:  Booth willow is dioecious.  The fruit is contained
in a dehiscent capsule that releases many seeds.  Seeds are dispersed by
wind or water.  Optimum seed production occurs between 2 and 10 years
[1,14].  The seeds of Booth willow are short-lived and require newly
deposited or recently scoured sand or gravel bars for germination [16].
Germination is inhibited on sites with a continuous cover of tree litter
or those with indirect sunlight [3,14].  Seed germination occurs over a
broad temperature range, 41 to 77 degrees Fahrenheit (5-25 deg C).  This
appears to be a compensatory mechanism because of the short seed life
[3].

Vegetative reproduction:  Booth willow sprouts readily from the root
crown or basal stem.  Booth willow will sprout vigorously following
cutting regardless of cutting season, but vigor is more pronounced if
cutting occurs during the dormant season [3,14].  Booth willow is highly
tolerant of frost and flooding.  One adaptation under these conditions
is the formation of a soft, spongy tissue called aerenchyma.  This
tissue enlarges the lenticels in the stems and permits more efficient
gas exchange and regeneration of roots.  Growth is severely limited when
water levels are maintained at or above the root crown.  Adventitious
rooting will occur above the flooded soil [20].


SITE CHARACTERISTICS : 
High moisture requirements limit Booth willow to riparian and lacustrine
areas, and in bottomlands with a high water table, such as wet meadows,
fens, bogs, and swamps [1].  Booth willow is best represented in
riparian communities within the Douglas-fir (Pseudotsuga menziesii) zone
and sagebrush/grass valley habitats.  It is also found in Engelmann
spruce (Picea engelmanii) dominated streambottoms in the upper
Douglas-fir zone [1,34].  Booth willow is a transitional species between
low-middle and middle elevations and between middle and middle-high
elevations [1]. It can be found intermittently in the lower subalpine
zone [24,33].  Booth willow is shade intolerant and grows best in full
sunlight [1,14].

Elevational range:  The elevational range for Booth willow in several
states is as follows [1,24,34]:  

           Utah:  5,300 to 10,300 feet (1,615-3,140 m)
           Idaho:  7,400 to 8,800 feet (2,255-2,685 m)
           Wyoming:  5,900 to 7,800 feet (1,800-2,380 m)
           Nevada:  5,800 to 8,300 feet (1,770-2,532 m)

Soils:  Booth willow is usually found on moist sandy or gravelly soils
but is adapted to a wide variety of soil textures [12,24].  The general
soil pH range for willows is 5.5 to 7.5.  Booth willow will tolerate
moderately alkaline soils but does poorly in strongly acidic or alkaline
conditions [14].  Growth of Booth willow is severely reduced when water
levels are maintained at or above the root crown for extended periods.

Plant associates:  Booth willow is commonly associated with the
following species:  Geyer willow, Drummond willow (Salix drummondiana),
thinleaf alder (Alnus tenuifolia), redosier dogwood (Cornus
stolonifera), water birch (Betula occidentalis), beaked sedge (Carex
rostrata), water sedge (C. aquatilis), bluejoint reedgrass
(Calamagrostis canadensis), mountain big sagebrush (Artemesia tridentata
ssp. vaseyana), bearberry honeysuckle (Lonicera involucrata), wood's
rose (Rosa woodsii), false-Solomons-seal (Smilacina stellata), field
horsetail (Equisetum arvense), bluegrass (Poa spp.), and sweet scented
bedstraw (Gallium triflorum) [1,2,12,24,34].


SUCCESSIONAL STATUS : 
Obligate Initial Community Species

Booth willow is found in early to mid seral plant communities.  It is a
pioneer species on recent alluvial deposits and on recently disturbed
sites [34].  In Montana, the successional trend on former beaver ponds
or stream channels is from open water to beaked sedge or water sedge
communities to eventual codominance by Booth willow and other willow
species.  If the stand dries out, Booth willow will be replaced by
species better adapted to more xeric conditions [12].  Booth willow has
low shade tolerance and therefore loses dominance on sites that are
heavily forested or succeeded by more shade-tolerant species [14].


SEASONAL DEVELOPMENT : 
Booth willow flowers in late spring or midsummer, from May to June.  The
fruit ripens soon after plant flowering, followed by seed dispersal in
late July and early August [14,35].
 

Related categories for Species: Salix boothii | Booth Willow