TITLE: Ecological Units of the Northern Region: Subsections
          Source Scale 1:500,000

This feature class displays the subsection level of the National Hierarchical
Framework of Ecological Units published in 1997 (USDA INT-GTR-369, Nesser et.al 1997). 
Subsections are smaller areas of sections with similar surficial geology, lithology,
geomorphic process, soil groups, subregional climate, and potential
natural communities (ECOMAP 1993). Each subsection has landscape
components that differentiate it from adjacent subsections. The
differentia include geologic materials, geomorphic features and
climate. Other components, or accessory characteristics, such as
soils and vegetation are used to describe the subsections but are
not used to delineate the units.

The Section and Subsection digital data was produced following the hard-copy version of the above
mentioned publication, in conjunction with the electronic publication of 
Landtye Associations of the Northern Region (USDA RMRS-GTR-2-CD, Ford et.al 1998)

Polygon attributes of the Subsections represent the categories of the National Ecological Hierarchy of Ecological Units. 
Attributes are:
SUBSECTION
SECTION
PROVINCE
SUB_TEXT - Descriptive name of the Subsection
SEC_TEXT - Descriptive name of the Section
PROV_TEXT - Descriptive name of the Province
 
Polygon attributes of the Sections represent the categories of the National Ecological Hierarchy of Ecological Units. Attributes are:
SECTION
PROVINCE
SEC_TEXT - Descriptive name of the Section
PROV_TEXT - Descriptive name of the Province

This data was created by USDA USFS Region One Soil Scientists using traditional mapping techniques
of mylar overlays on topographic base maps which were later manually digitized.