their contribution as effective and valid as possible. It
should be remembered that they also participate in
reaching conclusions and recommendations from the trials.
 The most common experimental design used in on-farm
research is probably randomized complete blocks, usually
with four replications. Split-plot arrangements are not
encouraged, but may be necessary when ecological
conditions or the nature of the variables prevent a
complete randomization of plots, as, for example, when
comparing fertilizer levels with and without irrigation.
The fertilizer levels are randomized within larger blocks
that are either irrigated or rainfed. Another example
would be to minimize cultivar border effects by
randomizing plant populations within larger blocks that
are cultivars.

FIELD DATA MANAGEMENT

Recording

 By its very nature, the information recorded in
on-farm trials must be less than in trials conducted on
experiment stations. The minimum necessary information
should be taken. Since experiments on farmers' fields
cannot receive the same day-to-day attention as station
experiments, it is advisable to increase the number of
locations rather than become involved in data collection
with too much detail in fewer locations. Those in charge
of on-farm trials must make every possible effort to
reduce to a minimum the time between completion of
recording data and the issuing of recommendations. Never
forget that farmers develop high expectations when
something is done on their farms, and their curiosity must
be satisfied as quickly as possible if their support and
assistance are to continue.
 It is important to decide how records are going to be
managed before experiments are conducted. Developing
standard procedures of data recording helps speed
processing and analysis, and contributes in turn to faster
conclusions and earlier recommendations. It also makes
information more reliable and easier to file and retrieve.
The availability or absence of electronic data-processing
facilities should be a prime consideration in planning
recording techniques.