Figure 16.10. Ridge tillage involves row planting on ridges (left), which are rebuilt with a weed cultivation/ridging operation during the growing season (right).
Strip tillage (figure 16.8, right) uses a similar
WHIcH TIllAgE SYSTEM FOR YOUR FARM?
approach, but the tillage shanks are shallower (typically
The correct choice of tillage system depends on climate,
to 8 inches), thereby reducing energy consumption.
soils, cropping systems, and the farm’s production
In temperate climates, zone building and strip tillage
objectives. Some general guidelines are provided in the
are often performed in the fall before spring row crop
following paragraphs.
planting to allow for soil settling. Some farmers inject
Conventional grain and vegetable farms have great
fertilizers with the tillage operations, thereby reducing
flexibility for adopting reduced tillage systems, because
the number of passes on the field.
they are less constrained by repeated manure applica-
The zone planter (figure 16.9) can also be used as a
tions (needed on livestock farms) or mechanical weed or
single-pass system when deeper disturbance is not needed.
rotation crop management (needed on organic farms).
Ridge tillage (figure 16.10) combines limited tillage
In the long run, limited disturbance and residue cover
with a ridging operation and requires controlled traffic.
improve soil health, reduce erosion, and boost yields. A
This system is particularly attractive for cold and wet
negative aspect of these systems is the transition period,
soils, because the ridges offer seedlings a warmer and
as discussed above, and changes in weed spectrum from
better-drained environment. The ridging operation can
annual to perennial plants. This may require differ-
be combined with mechanical weed control and allows
ent timing and methods of weed control. Combining
for band application of herbicides. Ridge tillage often
reduced tillage with the use of cover crops frequently
decreases the cost of chemical weed control, allowing
helps reduce weed problems. Weed pressures typi-
for about a two-thirds reduction in herbicide use. In
cally decrease significantly after a few years, especially
vegetable systems, raised beds—basically wide ridges that
if perennials are under control. Mulched cover crops,
also provide better drainage and warmer temperatures—
as well as newly designed mechanical cultivators, help
are often used.
provide effective weed control in high-residue systems.
Some innovative farmers use no-till combined with a
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Building SoilS for Better CropS: SuStainaBle Soil ManageMent