Vegetation Classification and Mapping Project Report - USGS

Appendix C: Global and local plant community descriptions
herbaceous species, such as Achnatherum hymenoides, Chaenactis stevioides, Cryptantha sp.,
Cymopterus newberryi, Bouteloua gracilis, Ipomopsis gunnisonii (= Gilia gunnisonii), Lappula
occidentalis, Muhlenbergia porteri, Muhlenbergia pungens, Muhlenbergia torreyi, Pascopyrum
smithii, Plantago patagonica, Scleropogon brevifolius, Sphaeralcea coccinea, and Sporobolus
cryptandrus, may be present with low cover (Francis 1986, Muldavin et al. 2000b). Biological
soil crusts may be extensive in undisturbed examples of this association.
Petrified Forest National Park. Four relevés were classified as Pleuraphis jamesii - Sporobolus
airoides Herbaceous Vegetation. The total vegetation cover of these stands ranged from 13 to
18% (average 15%) and consisted of a shrub stratum with 1 to 6% cover (average 3%) and an
herbaceous stratum with 10-15% cover (average 12%). The species diversity ranged from 17
to 33 species (average 25 species). The vegetation was codominated in the herbaceous layer
by Pleuraphis jamesii with 2-4% cover (average 3%) and Sporobolus airoides with 2-8% cover
(average 4%).
Most abundant species:
Stratum Global species PEFO species
Herb.(field) Pleuraphis jamesii, Sporobolus Pleuraphis jamesii, Sporobolus
airoides
airoides
Other noteworthy species:
Global species
Data are not available.
PEFO species
Data are not available.
References:
Bourgeron and Engelking 1994, CONHP unpubl. data 2003, Driscoll et al. 1984, Francis 1986, Hansen
et al. 2004b, Muldavin et al. 1998b, Muldavin et al. 2000b, West et al. 1972, Western Ecology Working
Group n.d.
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