III. No-Till Farming Systems - nifty

failure) are increased when the levels of technology and/or management are decreased,
i.e. cheap no-tillage solutions greatly heighten the risk of failure.
The authors illustrate how technical differences between a range of no-tillage
machines can be traced back to how their openers operate in the soil. In this respect,
the authors dissect opener functions in greater detail than has hitherto been
reported elsewhere. For example, the authors examine an extensive range of
opener designs that exist, in terms of how they create seed slots and how (or
whether) they cover these slots. They even quantify the value of different forms
of slot covering material, distinguishing between loose soil and mulch as well as
combinations of the two.
Then, in separate chapters, the authors detail the biological responses of various
basic opener designs in dry soils, wet soils, and a wide range of surface residues.
The authors highlight the unique value of vapor-phase soil water in no-tillage,
since the very act of performing conventional tillage virtually eliminates vaporphase
water from performing any significant role in tilled soils. Similarly, the
authors explore the role of soil aeration, infiltration and earthworms in wet soils
and how all of these factors can be influenced (or more importantly, harnessed)
by good no-tillage opener designs.
The importance of, and opener-design-options for, controlling seeding depth in
varying soil conditions are examined, together with the desirability of “double
shooting” (delivering separately) seed and fertilizer under no-tillage. Its effects on
crop yield (compared with broadcast fertilizers) are examined together with the
pros and cons of a range of design options for banding fertilizer separately from
seed during no-tillage.
Since true no-tillage has much to do with minimizing surface residue disturbance,
a separate chapter is devoted to comparing minimum and maximum residue disturbance
options in terms of both crop responses and technology design options
and a further chapter examines the mechanisms and problems of residue handling
by openers.
There is a special chapter on no-tillage for forage cropping that supports the view
that all competing vegetation does not necessarily need to be removed prior to
seeding when crops are to be fed to animals. The chapter on management of notillage
systems places emphasis on planning and even gives an example of typical
time-line decision-making.
Having outlined the major factors influencing the biological success or failure of
no-tillage machines and systems, the book moves logically into an analytical discussion
of critical engineering aspects of machine design as they relate to both
small-scale and large-scale machines. The book acknowledges that some of the
more desirable design features of large-scale machines are impractical and uneconomic
to reproduce on small-scale machines that are constrained by limited budg-
506