Vegetation Classification and Mapping Project Report - USGS

Appendix C: Global and local plant community descriptions
Vegetation hierarchy:
Physiognomic class III Shrubland
Physiognomic subclass III.A. Evergreen.shrubland
Physiognomic group III.A.4. Microphyllous.evergreen.shrubland
Physiognomic subgroup III.A.4.N. Natural/Semi-natural.microphyllous.evergreen.shrubland
Formation name III.A.4.N.a. Lowland.microphyllous.evergreen.shrubland
Alliance name
Ecological systems placement:
Artemisia filifolia.Shrubland.Alliance.(A.816),.
Sandsagebrush.Shrubland.Alliance
Ecological system unique ID
CES304.775
CES304.793
Ecological system name
Inter-Mountain.Basins.Active.and.Stabilized.Dune
Southern.Colorado.Plateau.Sand.Shrubland
NatureServe conservation status:
Global rank. GNR (14-Aug-2001).
Distribution:
Globally. This sand sagebrush shrubland association is widespread on sandy sites in the Colorado
Plateau of Utah, Colorado, Arizona and New Mexico.
Petrified Forest National Park. Artemisia filifolia Colorado Plateau Shrubland was identified
from seven relevés within Petrified Forest National Park. All of these relevés occurred on
sandy surfaces or sand dunes. They were sampled throughout the monument and included the
northern wilderness area southeast of Pintado Point and west of Lithodendron Wash, west of
Dry Wash and west of Crystal Forest, near The Flattops extending to the southern wilderness
area, and south of Jim Camp Wash.
Environmental summary:
Globally. This sand sagebrush shrubland association is widespread on sandy sites in the
Colorado Plateau of Utah, Colorado, Arizona, and New Mexico. This common shrubland association
occurs on sandy sites on valley floors, valley sides, stream terraces, stabilized dunes
and sandsheets, benches, floodplains, and alluvial fans. Most sites are level to gently sloping,
with a few on moderate slopes (up to 21%), and may be oriented to any aspect, although there
is a slight tendency to occur on warmer southerly aspects. Elevations range from 1122 to 1769
m (3680-5803 ft). Sand or bare soil covers most of the unvegetated ground surface, although
cryptobiological soil crusts may have up to 40% cover. Soils are sandy and derived from local
sandstones, alluvium, or eolian deposits.
Petrified Forest National Park. This association occurred between 1622 and 1730 m (5525-
5700 ft) elevation. Slope ranged from none to moderate (0-18%, average 7%). Only one relevé
had any surface rocks—a mixture of basalt and sandstone.
USFWS wetland system: Not applicable.
Vegetation description:
Globally. Total vegetation cover ranges broadly, from sparsely vegetated disturbed and alluvial
terrace sites with less than 5% total cover to stable, well-developed communities with more
than 50% cover. Regardless of cover, the vegetation is characterized by an open shrub canopy
of Artemisia filifolia, usually mixed with other shrubs, especially Atriplex canescens, Ericameria
nauseosa, and Opuntia spp. Less commonly, the shrub layer will include Vanclevea stylosa,
Eriogonum leptocladon, or Sarcobatus vermiculatus. Coleogyne ramosissima, Ephedra viridis,
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