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4. Soil Management Considerations
Reduced tillage or conservation tillage
Reduced tillage, often called “conservation tillage,” is any method that involves fewer passes than
conventional tillage. The previous crop residue or cover crop is often left on the soil surface for soil
protection.
Goals of reduced tillage
Physical/Chemical
•
Reduce compaction
•
Increase aggregate stability
•
Conserve moisture
•
Reduce erosion
•
Conserve organic matter
Biological
•
Maintain yields
•
Improve microbial habitat
•
Minimize weed germination
Operational
•
Reduce fuel use
•
Reduce farm traffic
Note: several of these benefits can also result
in reduced carbon emissions from both soil
and equipment.
Problems of reduced tillage
Equipment needed
•
Investment in new equipment may
require significant capital outlay.
Residue management
•
Heavy residue can interfere with
planting and seedling establishment.
•
In some cases heavy residue can
harbor diseases and pests.
Weed control
•
Weed control has been reported as
being problematic under reduced
tillage systems.
•
In long-term reduced tillage systems,
the weed spectrum may change from
annuals to perennials.
Photo: John Idowu