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4. Soil Management Considerations
Fields may be tilled before seeding (seedbed
preparation), during planting, after planting
(cultivation and incorporation, weed removal,
mixing in soil amendments, breaking disease
and pest cycles), or after harvest (managing
crop residue). But every engagement of tillage
tools breaks up soil, exposes soil organic
matter to oxidation and loss, and disrupts the
soil food web.
Characteristics of conventional tillage
Often the desired outcome of conventional
tillage is a “clean field.”
•
Plowing – cutting, lifting, turning over,
and partly pulverizing soil
•
Disking – breaking up ground to make
soil aggregates smaller and finer
•
Ripping – breaking up deep,
compacted soil layers to encourage
root growth and facilitate water
movement
•
Cultivation – uprooting weeds
between rows of growing vegetation
Tillage Management
Glossary
Tillage
the use of mechanical tools to loosen soil and/
or break compaction for the purpose of seed
emergence and crop growth and development.
What is Tillage?
However, there are detrimental effects to soil
associated with conventional tillage practices.
Physical/Chemical
•
Loss of soil structure, porosity, and
organic matter
•
Compaction (formation of plow pans),
poor drainage, reduced water-holding
capacity during droughts
•
Increased soil erosion and pesticide
runoff
•
Surface crusting (soil dries out quickly
forming an impenetrable crust)
Biological
•
Loss of beneficial soil organisms
•
Reduced root growth
•
Increased microbial respiration leading
to loss of soil organic matter