BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Elymus trachycaulus | Slender Wheatgrass 



GENERAL BOTANICAL CHARACTERISTICS : 
Slender wheatgrass is a perennial, cool-season, short-lived, coarse,
tufted bunchgrass.  Leaves are from 3 to 13 inches (8-33 cm) long and
0.25 to 0.5 inch (0.6-1.3 cm) wide, with basal leaves longer than upper
leaves.  The culms are erect, ranging from 6 to 48 inches (8-120 cm) in
height, and bear terminal, erect spikes [37,55].  The root system is
dense, consisting of coarse and fine fibrous roots which extend beyond
12 inches (30 cm) in depth.  One author has reported this species as
having short rhizomes [23].  The dense root system makes this species
moderately drought tolerant [44].


RAUNKIAER LIFE FORM : 
   Chamaephyte


REGENERATION PROCESSES : 
Sexual:  Slender wheatgrass is a self-pollinated or wind-pollinated
species with heavy seed production [5,20,23].  Seed is disseminated by
transport on animal hides.  The seed, stored in seed banks, remains
viable for 3 to 6 years, with a germination capacity of 80 to 90
percent.  This species requires 1- to 2-month short night/long day
stratification prior to germination.  The temperature and light regime
required for optimal germination fluctuates from a daily minimum of 59
degrees Fahrenheit (15 deg C) for 16 hours without light to a maximum of
77 degrees (25 deg C) for 8 hours with light [20,42].  Slender
wheatgrass requires a moderately moist bare mineral or lightly mulched
seedbed.  It is a good competitor on disturbed sites for the first 2 to
3 years.  Seedling establishment is often poor in older communities
because seedlings to not grow well in thatch or other heavy litter [40].
Generally, seed dispersal and seedling establishment is the primary
method of reproduction in this species [23].  Considerable variation,
however, has been noted among northern ecotypes in both seed production
and vegetative reproduction.

Vegetative:  Slender wheatgrass reproduces asexually by tillering [23].


SITE CHARACTERISTICS : 
Widely distributed, slender wheatgrass has numerous ecotypes that occur
in widely differing climates.  Slender wheatgrass is found on semiarid
ranges, in temperate and boreal forests, and in subalpine, alpine, and
subarctic habitats [8,23].  More detailed site characteristics are as
follows:

Soil:  Slender wheatgrass grows in dry to moist, medium-textured soil.
It tolerates silt and clay but does best on sandy loam.  This species
has a high salt tolerance.  Soil pH usually ranges from moderately acid
to moderately alkaline, although it has been reported growing in soils
with a pH as high as 8.8 [20,23].

Precipitation:  Slender wheatgrass requires from 10 to 20 inches (25 -
50 cm) of annual precipitation [20].

Elevation:  The following ranges in elevation have been reported for
slender wheatgrass in several western states [24,25,38]:

AZ: 5,000-12,000 ft (1,370-3,660 m)
CA: below 11,000 ft (3,330 m)
CO: 4,500-12,000 ft (1,370-3,600 m)
UT: 4,500-12,200 ft (1,370-3,660 m)


SUCCESSIONAL STATUS : 
Obligate Initial Community Species

Slender wheatgrass is a pioneer in primary and secondary succession.  It
is among the first grasses to establish in gravelly pockets of soil on
talus slopes of the Wasatch Plateau, Utah, and has colonized abandoned
coal mine spoils in Alberta, Canada [17,46].  Slender wheatgrass is
often dominant in early seral grassland communities due to its high seed
production, and is also a dominant or codominant understory species in
early seral forest and woodland communities [10,23].  Populations
decrease in all three community types at later stages.  Slender
wheatgrass planted with crested wheatgrass (Agropyron cristatum) on a
disturbed grassland range in Alberta declined from 69.5 percent of total
herbage production in the first year to 2.6 percent after 4 years [23].
Litter buildup in older communities reduces flowering and seedling
establishment in this species [41,43].  It is somewhat shade tolerant
and persists in the community as a minor plant associate through the
climax stage [23].


SEASONAL DEVELOPMENT : 
Development varies depending upon latitude, elevation, and time of
snowmelt.  Generally, slender wheatgrass develops as follows [17,20,55]:

                       Northern Range         Southern Range
growth starts          following snowmelt     early spring
flowers                July-Aug               May-Oct
seeds ripe             Aug-Sept               June-Nov
seeds disseminated     Sept-Oct               Sept-Nov      

Related categories for Species: Elymus trachycaulus | Slender Wheatgrass