Restrictive Soil Layers

Question 1

Wheel Track compaction

Answer 1

• occurs under vehicle and implement tires or tracks
• surface soil is compacted

Question 2

Tillage induced compaction

Answer 2

• occurs at depth to which the tillage implement works the soil

Question 3

Crusting

Answer 3

• caused by destruction of structure of soil surface by heavy rains followed by drying
• soils with high sil and low organic matter contents are subject to crusting

Question 4

Naturally occuring layers

Answer 4

• fragipans
• hardpans
• claypans
• caliche

Question 5

subsurface compaction

Surface compaction

Answer 5

subsurface

• soil bulk density increases and percent porosity decreases
• restrict water air movement and root penetration

surface compaction

• infiltration of water and gas exchange reduced

Question 6

Preventing Restrictive Layers

Answer 6

• keeping crop residues on the soil
• maintain water stable aggregates at the surface
  
  • by organic matter additions
  • surface residue management
  • tillage practices
• minimize heavy equipment traffic
  
  • particulary over wet soil