BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Leymus ambiguus | Colorado Wildrye 



GENERAL BOTANICAL CHARACTERISTICS : 
Colorado wildrye is a native, cool-season, loosely caespitose, erect,
long-lived perennial bunchgrass that occasionally produces short
rhizomes [2].  Culms typically range from 24 to 44 inches (60-110 cm) in
height; spikes are usually 3.2 to 6.8 inches (8-17 cm) long and have two
spikelets at most nodes [1,2].  Leaves are lax, spreading, and commonly
extend up the entire culm.  Compared with the morphologically similar
Salina wildrye (Leymus salinus), Colorado wildrye tends to be more lush
in appearance due to its abundant vegetative growth and leafy culms.
Most plants are tetraploid (2N = 28), but naturally occurring
populations containing both tetraploid and octoploid (2N = 56)
individuals have been reported [2]].




RAUNKIAER LIFE FORM : 
   Hemicryptophyte


REGENERATION PROCESSES : 
Colorado wildrye reproduces both sexually and vegetatively.  Plants
expand vegetatively through tillering.  In more mesic situations plants
sometimes form short rhizomes [1].  Limited data indicate that this
species exhibits strong seed habits.  Initial seedling establishment is
generally high due to good germination and rapid seedling growth.  Final
establishment, however, is reportedly low, perhaps as a result of the
xeric nature of most sites [17].


SITE CHARACTERISTICS : 
Colorado wildrye is typically associated with dry, steep, rocky sites at
elevations ranging from 5,200 to 8,500 feet (1,585-2,591 m) along the
eastern slope of the Rocky Mountains.  Characteristic sites include
boulder strewn hillsides and canyon walls [1].  Plants occur on all
aspects but grow best on south-facing exposures.  Where this bunchgrass
grows with Rocky Mountian juniper (Juniperus scopulorum), soils are
usually coarse texured, shallow, and derived from colluvial and residual
gneissic and schistic rock; parent materials tend to be exposed at the
ground surface [11].  Other common plant associates include
true-mountain mahogany (Cercocarpus montanus), chokecherry (Prunus
virginiana), wax current (Ribes cereum), big sagebrush (Artemisia
tridentata), bitterbrush (Purshia tridentata), and mountain maple (Acer
glabrum).


SUCCESSIONAL STATUS : 
Self-perpetuating stands of Colorado wildrye are indicative of climax
conditions on rocky, xeric grassland sites along the Colorado Front
Range [13].


SEASONAL DEVELOPMENT : 
Information on the phenological development of Colorado wildrye is scant.
Cronquist and others [5] reported that plants in the Intermountain
region bloom between late May and July.  However, it is unknown to what
extent this data can be applied to the more restricted range of Colorado
wildrye as described by Barkworth and Atkins [2].

Related categories for Species: Leymus ambiguus | Colorado Wildrye