General Soil and Landform Information from Agroecological Resource Area (ARA)


This data file contains information about the climate index, landform, texture class and soil development as identified on the Agroecological Resource Area maps for Alberta, Saskatchewan and Manitoba.

One record per ARA.

Item Name Description
PROV Province
ARR Agroecological Resource Region
CLIMINDX Climate Index
SOILDEV Soil Development

General Conventions

The following conventions were used to show combinations of more than one category in each variable:

  • dominantly one category, generally occupying over 70% of the ARA, eg. [A]
  • mainly one category with significant proportions (20-40%) of a second, eg. [A(B)]
  • about equal amounts of two categories, eg. [A - B].

Landform Classes

  • U or L undulating and level plains with slopes <5%
  • H hummocky uplands or hilllands with slopes 5-15%
  • M rolling uplands with slopes 5-15%
  • S steeplands with slopes >15%

Texture Classes

Eight classes were recognized, based on particle size distribution of an average of the surface and subsoil.

  • S coarse sand and loamy sand
  • SL moderately coarse sandy loam
  • L medium to moderately fine loam
  • SIL silt loam
  • CL clay loam
  • SIC silty clay
  • C clay
  • O organic

Soil Development Classes

  • BR Brown Chernozemic
  • DB Dark Brown Chernozemic
  • BL Black Chernozemic
  • DG Dark Gray Chernozemic
  • SS Solodized Solonetz
  • SO Solods and Solonetzic intergrades
  • GL Gray Luvisol
  • DG Dark Gray Luvisolic
  • BS Brunisolic
  • RE Regosolic
  • GY Gleysolic
  • O Organic
  • R Rock

Agro-Climate Classes

  • 2A Slight Moisture Limitation
  • 3A Moderate Moisture Limitation
  • 2H Slight Heat Limitation
  • 3H Moderate Heat Limitation
  • 4H Severe Heat Limitation
  • 5H Very Severe Heat Limitation

Moderate Limitation means that one of the major cereal crops (wheat, barley, canola) is limited to less than 15% of the crop area.

Severe Limitation means that less than 30% of the cultivated area is in annual cereals for grain.

Very Severe Limitation is essentially beyond arable agriculture.