Soils of Yellowstone National Park

Objectives were to provide baseline soil data at an Order IV
level, meaning that soils are classified and mapped at a
scale suitable for broad resource planning, and to provide
basic soils information for use in research, resource
management, and interpretive and educational purposes.
Resource management planners can use it to determine the
effects of different management alternatives. Research
personnel can use it to plan site locations, correlate soil
properties with existing information, extrapolate site data,
and help place site data in a landscape context. Ecologists
can better place communities of plants and animals into a
landscape setting using soils as a component of the
ecosystem. Wildfire personnel can use the information to
predict vegetation recovery, potential wildfire soil damage,
and suppression hazards. Teachers and students can study
patterns of soils and how they relate to wildlife use,
vegetation patterns, or visitor impact. Specialists in
cultural resources, construction and buried services can use
this survey to locate which areas require more intensive
field studies.

The soils of Yellowstone National Park were being mapped
between 1988 and 1996 to provide better information about
their nature and distribution. The coverage of the soils of
Yellowstone Park of 1996 provides baseline soil data at an
Order IV level. The information can be used for site-specific
work only after field verification. Aerial photography taken
between 1969 and 1971, surficial geology maps completed in
1970's, existing digital maps (Habitat Types, Landforms and
Parent Material, DEM etc.), and information from site
observations were used. The map units delineate soil bodies
that occur together in repeating patterns on the landscape.
Map units include a combination of soils, mapped together to
reflect the scale of mapping, standards for purity, survey
objectives, and map readability (see section Entity and
Attribute Information for details). Rather than making map
units with predetermined interpretations in mind, major soil
properties were grouped to maximize differences between
groups and minimize differences within a group. This type of
grouping allows the user flexibility in developing
interpretations for specific interests. The location of each
map unit is shown on the detailed soil maps. Each map unit
and each soil in the survey area is described in detail,
including soil properties that affect land use and potential.
The ARC coverage contains about 5,000 polygons, and about 80
different map units, each a combination of soils. Primary
attributes are in the .PAT file, described in the Entity and
Attribute Information Section of this Metadataset.

We matched our maps with other ongoing and completed soil
surveys that border Yellowstone National Park to the extent
practicable, given the differing objectives between surveys,
their state of documentation, and our map unit definitions.
See Process Steps for details.

Using the GIS and the rule based system, soil maps were
produced automatically during the survey process. The draft
maps were used as field sheets in ground verification. Each
iteration of maps represented a stage of completion. We used
the GIS to flag unmapped areas (places where no rules existed
for that particular combination of soil forming factors) and
analyze those combinations. We resolved each case by 1) using
existing sample points or taking more field samples in those
areas to develop new map units, or 2) combining the areas
with other map units. The process of mapping was considered
complete when 1) all areas were mapped to an appropriate
level of quality and detail, 2) concepts represented by the
map units were logical and fit into the surrounding
landscapes, and 3) map units had adequate background
documentation. We edited the final draft maps using manual
and computer assisted methods to match ground observations
and to meet quality and readability standards. Each completed
draft map was overlain on a spatial model of slopes created
from a digital elevation model (DEM). Slope ranges and
distributions were developed and analyzed to help describe
ranges of properties.