FFA and Land Capability Class

Major Factors that keep the soil out of Land Capability Class I for FFA events

By Donald G. McGahan, Ph.D.
Revised: April 8, 2016

Land Capabilities and the overall Land Capability Class can be no better than the limitation placed on the soil by each factors class.

Example 1

If a field has a Coarse surface texture, then the best possible Capability Class is Class III.

Example 2

If a field is Gently Sloping (G.S.), this factor, alone, will limit the fields Land Capability Class to Class II.

Example 3

If a field is Slowly Permeable (and therefore not greater than a Land Capability Class II), of Coarse surface texture (and therefore not greater than a Land Capability Class III), Gently Sloping (and therefore not greater than a Land Capability Class II); these factors will put the field in Class III.

Example 4

If a field is Very Slowly Permeable (and therefore not greater than a Land Capability Class II), of Moderately Coarse surface texture (Class I), Gently Sloping (and therefore not greater than a Land Capability Class II); these factors trigger a Combination resulting in Land Capability Class III. (combinations common in FFA Developmental Events are listed in a separate heading below)

Class Highest LCC

Surface Texture 

  • Coarse not greater than Class III
  • Moderately Coarse not greater than Class I
  • Medium  not greater than Class I
  • Moderately Fine not greater than Class I
  • Fine not greater than Class I

Subsurface Texture

  • Coarse not greater than Class III
  • Moderately Coarse not greater than Class I
  • Medium not greater than Class I
  • Moderately Fine not greater than Class I
  • Fine not greater than Class I

Depth of Surface Soil and Subsoil 

  • Deep not greater than Class I
  • Moderate not greater than Class I
  • Shallow not greater than Class III
  • Very Shallow not greater than Class VII

Slope

  • Nearly Level not greater than Class I
  • Gently Sloping not greater than Class II
  • Moderately Sloping not greater than Class III
  • Strongly Sloping not greater than Class IV
  • Steep not greater than Class VI
  • Very Steep not greater than Class VI

Erosion – Wind and Water

  • None to Slight not greater than Class I
  • Moderate not greater than Class II
  • Severe not greater than Class VI
  • Very Severe not greater than Class VI

Permeability

  • Rapid not greater than III
  • Moderate not greater than I
  • Slow not greater than I
  • Very Slow not greater than II

Surface Runoff 

  • Rapid not greater than III
  • Moderate not greater than I
  • Slow not greater than I
  • Very Slow not greater than II

Combinations of Factor Classes Highest LCC

Listed below are the combinations of factors that affect the land classes.  When these factors are combined, they lower the Land Capability Class more than either of the factors would individually.

  • Very Slowly Perm. & Gently Sloping III
  • Very Slowly Perm. & Moderately Sloping IV
  • Very Slowly Perm. & Strongly Sloping VI
  • Very Slowly Perm. & Steep Slope VII
  • Very Slowly Perm. & Very Steep Slope VII
  • Very Slowly Perm. & Very Slow Runoff III
  • Very Slowly Perm. & Moderate Erosion IV
  • Shallow Soil & Moderate Slope IV
  • Shallow Soil & Strongly Sloping VI
  • Shallow Soil & Moderate Erosion IV
  • Shallow Soil & Very Severe Erosion VII
  • Gently Sloping & Moderate Erosion III
  • Coarse Soil & Moderate Slope IV

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