Vegetation Classification and Mapping Project Report - USGS

Introduction
bentonite soils (Chronic 1986). High
erosion rates in the Painted Desert also
make it diffcult for plants to become
established. From the Painted Desert rim,
the land slopes down to the southeast
through a series of wide erosional basins
to the Puerco River. The middle section of
the park is a relatively narrow strip of land
across this valley. In the southern third of
the park, the land has eroded into small
groups of buttes and mesas separated by
the wide expanses of Dry Wash and its
tributaries (Thomas et al. 2006).
1.5.7 Wildlife
Petrified Forest National Park provides
habitat for a diverse assemblage of
mammals, avifauna, and herpetofauna.
Mammals
The badlands and grasslands of the park
support 59 species of mammals. Coyotes
(Canis latrans) are found throughout the
park. Pronghorn antelope (Antilocapra
americana) occur in grasslands and
also occasionally in the badlands of
the park. Smaller mammals include
Gunnison’s prairie dog (Cynomys
gunnisoni), white-tailed antelope squirrel
(Ammospermophilus leucurus), Ord’s
kangaroo rat (Dipodomys ordii), and deer
mice (Peromyscus maniculatus).
Avifauna
Birds are the most speciose group of the
vertebrates, with 231 species known for
the park. The common raven (Corvus
corax) is one of the most conspicuous
bird species, often seen at parking lots
looking for handouts, as well as flying
overhead throughout the park. Golden
eagles (Aquila chrysaetos), various
hawks, and turkey vultures (Cathartes
aura) are also seen throughout the park.
Mockingbirds (Mimus polyglottos) and
thrashers are found in shrublands and
grasslands. Horned larks (Eremophila
alpestris) and meadow larks (Sturnella
neglecta) are common in the grasslands.
American robins (Turdus migratorius),
western bluebirds (Sialia mexicana),
and Townsends’s solitaires (Myadestes
townsendi) are found in areas with trees
(Thomas et al. 2006, http://www.nps.gov/
pefo).
Reptiles and Amphibians
Current records indicate that PEFO
supports seven species of amphibians,
including tiger salamanders (Ambystoma
tigrinum), Woodhouse’s toads (Bufo
woodhousii), red-spotted toads (B.
punctatus), and other toad species.
Amphibians hibernate in damp soils and
reproduce when rains form standing water
in pools and intermittent stream channels.
The 16 species of reptiles known to occur
in the park include the colorful collared
lizard (Crotaphytus collaris), gopher snake
(Pituophis catenifer), western rattlesnake
(Crotalus oreganus), and western box
turtle (Terrapene ornata).
No federally or state-listed threatened
or endangered wildlife reside in the park
(Thomas et al. 2006).
1.5.8 Vegetation
Biotic communities at PEFO belong to the
Colorado Plateau Semi-Desert Province
(Bailey et al. 1994) and include primarily
arid grasslands, xeric shrublands, and
sparsely vegetated badlands. Riparian
species, such as cottonwoods and willows
(Populus spp. and Salix spp.), grow along
some of the permanent streams. Within
the province as a whole, woodland is
the most extensive vegetation formation,
dominated by open stands of Colorado
pinyon pine (Pinus edulis) and several
species of juniper (Juniperus spp.), but the
extent of woodland in the park is limited.
Two rare plants are found in the park:
● gladiator milkvetch (Astragalus xiphoides)
occurs in several populations
● paper-spined cactus (Pediocactus
papyracanthus) occurs in pinyonjuniper
woodland.
One of the more important and least
recognized biological communities in this
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