Introductory
SPECIES: Tetradymia nuttallii | Nuttall Horsebrush 



ABBREVIATION : 
TETNUT

SYNONYMS : 
NO-ENTRY


SCS PLANT CODE : 
   TENU2


COMMON NAMES : 
   Nuttall horsebrush


TAXONOMY : 
Strother's 1974 revision of the genus Tetradymia recognizes Nuttall
horsebrush as Tetradymia nuttallii Torr. & Gray.  Strother put in
synonymy with T. glabrata the two entities, T. spinosa Nutt. and X T.
permizta Payson [9].


LIFE FORM : 
Shrub

FEDERAL LEGAL STATUS : 
No special status

OTHER STATUS : 
NO-ENTRY


COMPILED BY AND DATE : 
Kathy Ahlenslager, May 1986



LAST REVISED BY AND DATE : 
Kathleen E. Ahlenslager  December 1987



AUTHORSHIP AND CITATION : 
Ahlenslager, Kathleen E. 1987. Tetradymia nuttallii. In: Remainder of Citation

DISTRIBUTION AND OCCURRENCE
SPECIES: Tetradymia nuttallii | Nuttall Horsebrush 



GENERAL DISTRIBUTION : 
Nuttall horsebrush grows in the badlands of southwestern Wyoming, as
well as in dry barren hills and plains of northeastern Nevada, northern
Utah, and northwestern Colorado.


ECOSYSTEMS : 
   FRES29  Sagebrush
   FRES30  Desert shrub
   FRES35  Pinyon - juniper
   FRES36  Mountain grasslands
   FRES40  Desert grasslands


STATES : 
     CO  NV  UT  WY


ADMINISTRATIVE UNITS : 
     DINO


BLM PHYSIOGRAPHIC REGIONS : 
    3  Southern Pacific Border
    4  Sierra Mountains
    5  Columbia Plateau
    6  Upper Basin and Range
    7  Lower Basin and Range
    8  Northern Rocky Mountains
    9  Middle Rocky Mountains
   10  Wyoming Basin
   11  Southern Rocky Mountains
   12  Colorado Plateau
   16  Upper Missouri Basin and Broken Lands


KUCHLER PLANT ASSOCIATIONS : 
   K23  Juniper - pinyon woodland
   K38  Great Basin sagebrush
   K40  Saltbrush - greasewood
   K51  Wheatgrass - bluegrass
   K53  Grama - galleta steppe
   K55  Sagebrush steppe
   K63  Foothills prairie


SAF COVER TYPES : 
   239  Pinyon - juniper


SRM (RANGELAND) COVER TYPES : 
NO-ENTRY


HABITAT TYPES AND PLANT COMMUNITIES : 
Because Nuttall horsebrush is a seral species, it is not found as a
dominant, codominant, or indicator species in any habitat types.  It is
usually associated with sagebrush and shadscale vegetation types [7].

VALUE AND USE
SPECIES: Tetradymia nuttallii | Nuttall Horsebrush 



WOOD PRODUCTS VALUE : 
NO-ENTRY


IMPORTANCE TO LIVESTOCK AND WILDLIFE : 
Nuttall horsebrush is browsed in winter and early spring on desert
ranges and overgrazed areas.  It provides needed ground cover on dry
desert ranges [7].


PALATABILITY : 
Nuttall horsebrush is low in palatability.  Palatability ratings for
different livestock and wildlife species in Utah are as follows [4]:

Cattle                Poor
Sheep                 Poor
Horses                Poor
Pronghorn             Poor
Elk                   Poor
Mule deer             Poor
Small mammals         Fair
Small nongame birds   Poor
Upland game birds     Poor
Waterfowl             Poor


NUTRITIONAL VALUE : 
Nuttall horsebrush is rated poor in energy and protein value [4].


COVER VALUE : 
The degree to which Nuttall horsebrush provides environmental protection
during one or more seasons for wildlife species in Utah is as follows
[4]:

Pronghorn               Poor
Elk                     Poor
Mule deer               Poor
Small mammals           Fair
Small nongame birds     Fair
Upland game birds       Fair
Waterfowl               Poor


VALUE FOR REHABILITATION OF DISTURBED SITES : 



OTHER USES AND VALUES : 
NO-ENTRY


MANAGEMENT CONSIDERATIONS : 
NO-ENTRY

BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Tetradymia nuttallii | Nuttall Horsebrush 



GENERAL BOTANICAL CHARACTERISTICS : 
Nuttall horsebrush is a native, perennial, rigidly branched shrub that
grows up to 4 feet (12 dm) tall [8,10].


RAUNKIAER LIFE FORM : 
   Phanerophyte


REGENERATION PROCESSES : 
Nuttall horsebrush regenerates vegetatively through root crown
sprouting, as well as sexually via wind-dispersed seeds.  Although
flowers are highly fertile, seedlings are rarely observed in nature.
This is probably due to the harsh environment in which this species
occurs [9]. 


SITE CHARACTERISTICS : 
Nuttall horsebrush plants occur in sagebrush and shadscale communities
on badlands, and dry barren hills and plains from 4,300 to 6,900 feet
(1,300-2,100 m) [9].  Elevational ranges vary as follows [4]:

     from 5,600 to 6,500 feet (1,707-1,982 m) in CO
          4,500 to 6,000 feet (1,372-1,829 m) in UT
          6,200 to 6,200 feet (1,890-1,890 m) in WY


SUCCESSIONAL STATUS : 
Nuttall horsebrush is a seral species and has the ability to increase in
abundance during secondary succession through vigorously sprouting root crowns.
Although flowers are highly fertile, seedlings are rarely observed in nature. 
This is probably due to the harsh environment in which this species occurs [4].


SEASONAL DEVELOPMENT : 
Nuttall horsebrush plants generally bloom from late May to early July
[10].  Flowering dates are as follows [4]:

State   Earliest date oberved    Latest date observed
CO            July                     July
UT           June                     June
WY           June                     August

As typical with many xerophytes, the occurrence of flowering is
correlated with distribution and rainfall.  In very dry years some
individuals or entire colonies do not bloom at all, or bloom but fail to
mature fruits, probably due to decreases in water availability [9].

One way xerophytic species cope with a short growing season is by
maturing flowers simultaneously.  Often whole colonies of plants will
bloom at once, and most horsebrush plants within a colony will flower
within a few days of each other [9].

FIRE ECOLOGY
SPECIES: Tetradymia nuttallii | Nuttall Horsebrush 



FIRE ECOLOGY OR ADAPTATIONS : 
Plants of Nuttall horsebrush stand dormant throughout most of the year
on the dry ranges where they occur.  During a fire these much-branched
shrubs burn rapidly, with little heat transferred downward into the root
crowns.  Fire stimulates the root crowns to sprout [10].


POSTFIRE REGENERATION STRATEGY : 
   Small shrub, adventitious-bud root crown
   Ground residual colonizer (on-site, initial community)

FIRE EFFECTS
SPECIES: Tetradymia nuttallii | Nuttall Horsebrush 



IMMEDIATE FIRE EFFECT ON PLANT : 
The effect of fire on shrubs is more damaging than that on forbs and
grasses.  Fire not only destroys herbage, but destroys the stored
reserves of shrubs [3].  Nuttall horsebrush is considered a
fire-resistant species, as there is a 65 percent or greater chance that
at least 50 percent of a population will survive or reestablish after a
fire [10,11].


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
Nuttall horsebrush, which is capable of resprouting and rapid regrowth
after a fire, is favored over other plants that reestablish only by seed
[2].  Postfire regeneration response is considered rapid with 2 to 5
years required to approximate preburn frequency or cover [10].  Plants
quickly regain and surpass their original size.  The amount of sprouting
is affected by season and soil moisture, as these are factors which
contribute to burning intensity [3].

After a fire, crown-sprouting Nuttall horsebrush may initially dominate
sagebrush ranges.  In addition to the vigorous postburn production of
root crown sprouts, there is dynamic seedling establishment [12].


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
NO-ENTRY


FIRE MANAGEMENT CONSIDERATIONS : 
NO-ENTRY

REFERENCES
SPECIES: Tetradymia nuttallii | Nuttall Horsebrush 



REFERENCES : 

 .  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]

 .  Blaisdell, James P. 1953. Ecological effects of planned burning of
       sagebrush-grass range on the upper Snake River Plains. Tech. Bull. 1975.
       Washington, DC: U.S. Department of Agriculture. 39 p.  [462]

 .  Blaisdell, James P.; Murray, Robert B.; McArthur, E. Durant. 1982.
       Managing Intermountain rangelands--sagebrush-grass ranges. Gen. Tech.
       Rep. INT-134. Ogden, UT: U.S. Department of Agriculture, Forest Service,
       Intermountain Forest and Range Experiment Station. 41 p.  [467]

 .  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]

 .  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]

 .  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]

 .  McArthur, E. Durant; Blauer, A. Clyde; Plummer, A. Perry; Stevens,
       Richard. 1979. Characteristics and hybridization of important
       Intermountain shrubs. III. Sunflower family. Res. Pap. INT-220. Ogden,
       UT: U.S. Department of Agriculture, Forest Service, Intermountain Forest
       and Range Experiment Station. 82 p.  [1571]

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

 .  Strother, John L. 1974. Taxonomy of Tetradymia (Compositae:
       Senecioneae). Brittonia. 26: 177-202.  [2268]

.  Volland, Leonard A.; Dell, John D. 1981. Fire effects on Pacific
       Northwest forest and range vegetation. Portland, OR: U.S. Department of
       Agriculture, Forest Service, Pacific Northwest Region, Range Management
       and Aviation and Fire Management. 23 p.  [2434]

.  Wright, Henry A. 1972. Shrub response to fire. In: McKell, Cyrus M.;
       Blaisdell, James P.; Goodin, Joe R., eds. Wildland shrubs--their biology
       and utilization: Proceedings of a symposium; 1971 July; Logan, UT. Gen.
       Tech. Rep. INT-1. Ogden, UT: U.S. Department of Agriculture, Forest
       Service, Intermountain Forest and Range Experiment Station: 204-217. 
       [2611]

.  Young, Richard P. 1983. Fire as a vegetation management tool in
       rangelands of the Intermountain Region. In: Monsen, Stephen B.; Shaw,
       Nancy, compilers. Managing Intermountain rangelands--improvement of
       range and wildlife habitats: Proceedings; 1981 September 15-17; Twin
       Falls, ID; 1982 June 22-24; Elko, NV. Gen. Tech. Rep. INT-157. Ogden,
       UT: U.S. Department of Agriculture, Forest Service, Intermountain Forest
       and Range Experiment Station: 18-31.  [2681]

Related categories for Species: Tetradymia nuttallii | Nuttall Horsebrush