VALUE AND USE
SPECIES: Tortula ruralis | Twisted Moss 



WOOD PRODUCTS VALUE : 
NO-ENTRY


IMPORTANCE TO LIVESTOCK AND WILDLIFE : 
NO-ENTRY


PALATABILITY : 
NO-ENTRY


NUTRITIONAL VALUE : 
NO-ENTRY


COVER VALUE : 
NO-ENTRY


VALUE FOR REHABILITATION OF DISTURBED SITES : 
NO-ENTRY


OTHER USES AND VALUES : 
NO-ENTRY


MANAGEMENT CONSIDERATIONS : 
Cryptogamic soil crusts, including crusts formed by T. ruralis, are an
important component of many arid rangeland ecosystems in the western
United States.  They are important in the reduction of soil erosion, and
facilitate vascular plant seedling establishment by improving water
penetration and reducing runoff [22,23].  Soils with high electrical
conductivity, high phosphorous, and high salt contents facilitate the
formation of cryptogam crusts [1].  Heavy grazing, especially during
seasons of low precipitation, high temperature, and persistent winds can
seriously damage or destroy crusts formed by T. ruralis and other
cryptogams.  During these seasons, T. ruralis is most likely dormant and
brittle, and very susceptible to trampling by livestock [2].  In Navaho
National Monument, Arizona, T. ruralis was reduced from 6.3 percent
cover in ungrazed areas to 1.0 percent cover in heavily grazed areas
[6].

In semiarid and arid grasslands of Canyonlands National Park, Utah,
cryptogams, including T. ruralis, are instrumental in the build-up of
organic matter and soil nutrients.  Cryptogam cover stabilizes soils
eroded by heavy winds and torrential rains, especially in undisturbed
areas [27].  Relative abundance of T. ruralis was "significantly
reduced" in formerly grazed areas, but was high in undisturbed climax
grasslands.  The ungrazed areas of the park had an average of six
cryptogam species per site, with a total cryptogram coverage of 38
percent.  The formerly grazed areas had an average of two cryptogam
species per site, with a total coverage of 5 percent.  This difference
suggests that cryptogam species such as T. ruralis may play a more
important role in the stability of desert grasslands than previously
recognized.  The surface soils of formerly grazed areas had less organic
matter, less available phosphorous, and higher calcium content due to
slow sheet erosion caused by a lack of protection from an established
cryptogam cover [26].

In sagebrush types in Idaho and Oregon, T. ruralis litter and cover may
exclude or retard the growth of perennial grasses such as bluebunch
wheatgrass, Thurber needlegrass, and bottlebrush squirreltail [37,41].
However, this may be because T. ruralis occurs on sites that tend to
have less organic matter accumulation, decreased cation exchange
capacity, and decreased total nitrogen compared to sites that support
the perennial grass species [41].

Drought and dessication tolerance of T. ruralis has been studied
extensively in order to determine if similar physiological mechanisms
will improve drought resistance of commercial crops [13,21,34].  T.
ruralis can be dried to less than 20 percent of its original fresh
weight and will immediately resume protein synthesis upon rehydration
[13].  Metabolic activities will resume even after 70 years of
dessication [34].

Related categories for Species: Tortula ruralis | Twisted Moss