Crop
Management
Excessive
tilling can result in soil quality deterioration, soil loss through erosion, and
changes to local water quality. New programs are now gathering data to help
tackle the effect of crop production on the organic content and overall quality
of the soil. In addition, several land management practices are
revolutionizing Alberta farming. Reduced tillage, zero-till, and site-specific
management systems reduce the environmental impact of crop production. Specific
farm management practices that can reduce soil erosion include:
-
Minimum
tillagereducing the number of tillage passes to maintain at least 30
percent ground cover.
-
Zero-till
seeding (direct seeding)seed and fertilizer placement into previous
untilled stubble.
-
Cover
croppingplanting different types of crops in narrow alternate strips to
prevent erosion. Strips are usually planted across the slope or across the
direction of the prevailing wind.
-
Chemical
fallowleaving the land unplanted for one growing season. Herbicides
rather than tillage are used to control weeds.
-
Crop residue
managementmaintaining at least 30 percent ground cover by spreading straw
evenly across the land.
-
Fall-seeded
cropsplanting fall rye and winter wheat contributes to soil and water conservation and benefits local wildlife.
Technological
advances in crop production (chemical, equipment and management practices) have also lessened the severe soil erosion problems
associated with summerfallowing. In particular, herbicides are sometimes used to
replace one or more tillage operations to control weeds. Reduced soil erosion
means more topsoil, the potential for healthier soil, and consequently, better
crops.
As an
alternative to tillage, crop areas at high risk from water erosion due to steep
slopes or erodible soils may be better suited to forage production or grazing.
Wooded areas with poor soils and steep slopes can be left in their natural state
and managed as woodlots. In hilly, tilled areas, cultivating and planting across
the slope, rather than up and down, slows down the flow of water and increases
its absorption into the soil. Other ways to control water erosion include
maintaining organic material and crop residue cover, minimum tillage, zero-till,
and chemical fallow. To control severe water erosion, grassed waterways, lined
channels, drop structures, contour farming and gully control are necessary.
Alberta
Agriculture, Food and Rural Development has specialists throughout Alberta who
provide advice and information to farm managers about crop management systems
and soil conservation practices.
Department of the Environment. State of the Environment Report, Terrestrial Ecosystems. Edmonton: n.p., 2001. With permission from Alberta Environment.
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