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].

Related categories for Species: Tetradymia nuttallii | Nuttall Horsebrush