Introductory
SPECIES: Leymus ambiguus | Colorado Wildrye 



ABBREVIATION : 
LEYAMB

SYNONYMS : 
   Elymus ambiguus
   Leymus innovatus ssp. ambiguus


SCS PLANT CODE : 
   ELAM2


COMMON NAMES : 
   Colorado wildrye


TAXONOMY : 
The fully documented scientific name of Colorado wildrye is Leymus
ambiguus (Vasey & Scribner) D.R. Dewey. [2,3]. 


LIFE FORM : 
Graminoid

FEDERAL LEGAL STATUS : 
No special status

OTHER STATUS : 
NO-ENTRY


COMPILED BY AND DATE : 
N. McMurray/ September 1987


LAST REVISED BY AND DATE : 
NO-ENTRY


AUTHORSHIP AND CITATION : 
McMurray, Nancy E. 1987. Leymus ambiguus. In: Remainder of Citation

DISTRIBUTION AND OCCURRENCE
SPECIES: Leymus ambiguus | Colorado Wildrye 



GENERAL DISTRIBUTION : 
Colorado wildrye has a limited distribution along the east slope of the
Rocky Mountains in Colorado and New Mexico [2].  It occurs scattered
along the Colorado Front Range extending from Rocky Mountain National
Park southward to La Veta Pass in Herfano County.  Seemingly disjunct
populations also occur in the Magdalena and Manzano mountains of New
Mexicxo.  Although no specimens were found during field studies, Atkins
and others [1] speculated that plants occur in the intervening mountain
ranges.

Colorado wildrye as classified by Barkworth and Atkins [2] has a much
more restricted distribution than that described in other taxonomies.


ECOSYSTEMS : 
   FRES20  Douglas-fir
   FRES21  Ponderosa pine
   FRES23  Fir - spruce
   FRES29  Sagebrush
   FRES34  Chaparral - mountain shrub
   FRES35  Pinyon - juniper
   FRES36  Mountain grasslands


STATES : 
     CO  NM


ADMINISTRATIVE UNITS : 
     ROMO


BLM PHYSIOGRAPHIC REGIONS : 
    7  Lower Basin and Range
   11  Southern Rocky Mountains
   12  Colorado Plateau


KUCHLER PLANT ASSOCIATIONS : 
   K011  Western ponderosa forest
   K012  Douglas-fir forest
   K015  Western spruce - fir forest
   K037  Mountain-mahogany - oak scrub
   K055  Sagebrush steppe


SAF COVER TYPES : 
   206  Engelmann spruce - subalpine fir
   210  Interior Douglas-fir
   220  Rocky Mountain juniper
   237  Interior ponderosa pine


SRM (RANGELAND) COVER TYPES : 
NO-ENTRY


HABITAT TYPES AND PLANT COMMUNITIES : 
Colorado wildrye has been used as a climax indicator on montane
grassland communities in Colorado.  A classification listing Colorado
wildrye as an indicator or dominant species is:

Plant associations of Region Two: Potential plant communities of
   Wyoming, South Dakota, Nebraska, Colorado, and Kansas [13].

VALUE AND USE
SPECIES: Leymus ambiguus | Colorado Wildrye 



WOOD PRODUCTS VALUE : 
NO-ENTRY


IMPORTANCE TO LIVESTOCK AND WILDLIFE : 
Colorado wildrye has a low tolerance to grazing and generally rates low
in palatability, except perhaps in the early spring [17].


PALATABILITY : 
NO-ENTRY


NUTRITIONAL VALUE : 
NO-ENTRY


COVER VALUE : 
NO-ENTRY


VALUE FOR REHABILITATION OF DISTURBED SITES : 
Limited information indicates that Colorado wildrye exhibits strong seed
habits.  Good seed germination and rapid seedling growth contribute to
high initial establishment.  However, plants do not persist, and
long-term establishment is reportedly low, possibly due to the droughty
nature of sites characteristically occupied by this cool-season
bunchgrass [17].  Colorado wildrye is adapted for seeding in
pinyon-juniper, big sagebrush, and shadscale communities [17].


OTHER USES AND VALUES : 
NO-ENTRY


MANAGEMENT CONSIDERATIONS : 
NO-ENTRY

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].

FIRE ECOLOGY
SPECIES: Leymus ambiguus | Colorado Wildrye 



FIRE ECOLOGY OR ADAPTATIONS : 
Review of the available literature yielded no information pertaining
specifically to the fire ecology of Colorado wildrye.  Basin wildrye
(Leymus cinereus) is a morhpologicaly similar species characteristically
occupying saline and/or alkaline lowland and upland sites throughout the
Great Basin and northern Rocky Mountains [15].  General fire adaptations
for basin wildrye are summarized in the FEIS write-up for Leymus
cinereus.  The extent this information can be applied to Colorado
wildrye is currently unknown.


POSTFIRE REGENERATION STRATEGY : 
   Tussock graminoid
   Rhizomatous herb, rhizome in soil
   Initial-offsite colonizer (off-site, initial community)

FIRE EFFECTS
SPECIES: Leymus ambiguus | Colorado Wildrye 



IMMEDIATE FIRE EFFECT ON PLANT : 
Colorado wildrye typically forms small, loosely caespitose bunches that
grow in close aggreagation [1,12].  Such attributes suggest that this
bunchgrass burns rather quickly, with little heat transferred downward
into the crown [20].  As a result, basal buds located at or just below
the surface of the ground are not subjected to prolonged heating and
probably survive and resprout.  The rhizomatous nature of plants
occupying more mesic situations also suggests that this species is
somewhat resistant to fire mortality.  [For fire effects information on
a morphologically similar bunchgrass see Leymus cinereus write-up].


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
The steep, xeric nature of many of the sites characterized by this
perennial bunchgrass [1,11].  However, since plants typically occupy
rocky hillsides that may have burned less frequently but perhaps more
severely than surrounding areas, postburn reestablishment and response
may be somewhat different than that of basin wildrye (Leymus cinereus),
a morphologically similar bunchgrass adapted to saline and/or alkaline
lowland and upland sites in the Great Basin.  Fire response information
for basin wildrye is summarized in the FEIS write-up for Lyemus
cinereus.  The degree to which this information can be applied to
Colordo wildrye is not known at this time.


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
NO-ENTRY


FIRE MANAGEMENT CONSIDERATIONS : 
NO-ENTRY

REFERENCES
SPECIES: Leymus ambiguus | Colorado Wildrye 



REFERENCES : 

 .  Atkins, Riley J.; Barkworth, Mary E.; Dewey, Douglas R. 1984. A
       taxonomic study of Leymus ambiguus and L. salinus (Poaceae:Triticeae).
       Systematic Botany. 9(3): 279-294.  [2851]

 .  Barkworth, Mary E.; Atkins, Riley J. 1984. Leymus hochst.
       (Gramineae:Triticeae) in North America: taxonomy and distribution.
       American Journal of Botany. 71(5): 609-625.  [2889]

 .  Barkworth, Mary E.; Dewey, Douglas R. 1985. Genomically based genera in
       the perennial Triticeae of North America: identification and membership.
       American Journal of Botany. 72(5): 767-776.  [393]

 .  Bernard, Stephen R.; Brown, Kenneth F. 1977. Distribution of mammals,
       reptiles, and amphibians by BLM physiographic regions and A.W. Kuchler's
       associations for the eleven western states. Tech. Note 301. Denver, CO:
       U.S. Department of the Interior, Bureau of Land Management. 169 p. 
       [434]

 .  Cronquist, Arthur; Holmgren, Arthur H.; Holmgren, Noel H.; [and others].
       1977. Intermountain flora: Vascular plants of the Intermountain West,
       U.S.A. Vol. 6. The Monocotyledons. New York: Columbia University Press.
       584 p.  [719]

 .  Dittberner, Phillip L.; Olson, Michael R. 1983. The plant information
       network (PIN) data base: Colorado, Montana, North Dakota, Utah, and
       Wyoming. FWS/OBS-83/86. Washington, DC: U.S. Department of the Interior,
       Fish and Wildlife Service. 786 p.  [806]

 .  Dewey, Douglas R. 1983. Historical and current taxonomic perspectives of
       Agropyron, Elymus, and related genera. Crop Science. 23: 637-642.  [793]

 .  Dewey, Douglas R. 1983. New nomenclatural combinations in the North
       American perennial Triticeae (Gramineae). Brittonia. 35(1): 30-33. 
       [794]

 .  Eyre, F. H., ed. 1980. Forest cover types of the United States and
       Canada. Washington, DC: Society of American Foresters. 148 p.  [905]

.  Garrison, George A.; Bjugstad, Ardell J.; Duncan, Don A.; [and others].
       1977. Vegetation and environmental features of forest and range
       ecosystems. Agric. Handb. 475. Washington, DC: U.S. Department of
       Agriculture, Forest Service. 68 p.  [998]

.  Hess, Karl; Alexander, Robert R. 1986. Forest vegetation of the Arapaho
       and Roosevelt National Forests in central Colorado: a habitat type
       classification. Res. Pap. RM-266. Fort Collins, CO: U.S. Department of
       Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment
       Station. 48 p.  [1141]

.  Hitchcock, C. Leo; Cronquist, Arthur; Ownbey, Marion. 1969. Vascular
       plants of the Pacific Northwest. Part 1: Vascular cryptograms,
       gymnosperms, and monocotyledons. Seattle, WA: University of Washington
       Press. 914 p.  [1169]

.  Johnston, Barry C. 1987. Plant associations of Region Two: Potential
       plant communities of Wyoming, South Dakota, Nebraska, Colorado, and
       Kansas. 4th ed. R2-ECOL-87-2. Lakewood, CO: U.S. Department of
       Agriculture, Forest Service, Rocky Mountain Region. 429 p.  [3519]

.  Kuchler, A. W. 1964. Manual to accompany the map of potential vegetation
       of the conterminous United States. Special Publication No. 36. New York:
       American Geographical Society. 77 p.  [1384]

.  Lesperance, A. L.; Young, James A.; Eckert, Richard E., Jr.; Evans,
       Raymond A. 1978. Great Basin wildrye. Rangeman's Journal. 5(4): 125-127.
       [3829]

.  Lyon, L. Jack; Stickney, Peter F. 1976. Early vegetal succession
       following large northern Rocky Mountain wildfires. In: Proceedings, Tall
       Timbers fire ecology conference and Intermountain Fire Research Council
       fire and land management symposium; 1974 October 8-10; Missoula, MT. No.
       14. Tallahassee, FL: Tall Timbers Research Station: 355-373.  [1496]

.  Plummer, A. Perry; Christensen, Donald R.; Monsen, Stephen B. 1968.
       Restoring big-game range in Utah. Publ. No. 68-3. Ephraim, UT: Utah
       Division of Fish and Game. 183 p.  [4554]

.  Raunkiaer, C. 1934. The life forms of plants and statistical plant
       geography. Oxford: Clarendon Press. 632 p.  [2843]

.  Welsh, Stanley L.; Atwood, N. Duane; Goodrich, Sherel; Higgins, Larry
       C., eds. 1987. A Utah flora. Great Basin Naturalist Memoir No. 9. Provo,
       UT: Brigham Young University. 894 p.  [2944]

.  Wright, Henry A.; Bailey, Arthur W. 1982. Fire ecology: United States
       and southern Canada. New York: John Wiley & Sons. 501 p.  [2620]

.  Stickney, Peter F. 1989. Seral origin of species originating in northern
       Rocky Mountain forests. Unpublished draft on file at: U.S. Department of
       Agriculture, Forest Service, Intermountain Research Station, Fire
       Sciences Laboratory, Missoula, MT; RWU 4403 files. 7 p.  [20090]

.  U.S. Department of Agriculture, Soil Conservation Service. 1982.
       National list of scientific plant names. Vol. 1. List of plant names.
       SCS-TP-159. Washington, DC. 416 p.  [11573]

Related categories for Species: Leymus ambiguus | Colorado Wildrye