Knowledge, science, and practice in ecological weed management: farmer–extensionist–scientist interactions - Ecological Management of Agricultural Weeds - page 124

accuracy and time efficiency is a major practical challenge to weed ecologists
and weed extension specialists. Finding workable sampling and data record-
ing methods for use in group discussion and for comparisons in time and
space is one of the major initial areas of collaboration among farmers, exten-
sionists, and scientists when developing new programs in participatory learn-
ing for action. A few basic guidelines are available from previous studies. A
larger number of small units offers more precision than a smaller number of
large units (Lemieux, Cloutier & Leroux, 1992). Greater sampling intensity is
needed for accurate assessments of species that are less common (Marshall,
1988). Spatial distributions of weeds cannot be estimated with arithmetic
interpolation from quadrat counts (Marshall, 1988). Transects can be used
efficiently for sampling cover in large land areas (Morrison et al .,1993).Which
is the best method? When should farmers sample? How frequently should
they sample? Answers to these questions depend on the producers' interest,
the types of weeds, the type of crop, field size, and specific concerns of the
group. Midwestern USA maize and soybean growers and Central American
maize and bean farmers grow similar crops,but would have very different dis-
cussions about weed variability and uncertainty, and would propose different
observation methods.
Equipped with shared methods for weed measurement, farmers, exten-
sionists, and researchers can develop site-specific and group-specific learning
approaches as illustrated in the case studies of this chapter. These may be
derived from individual or group initiatives, and vary in their degrees of col-
laboration as shown in Figure 3.6.The farmer group context keeps both scien-
tist and farmer activities focused on farmer management of variability and
uncertainty for fewer weeds and higher yields.
Farmers,extensionists,and scientists each have different potential rewards
from participatory learning for action. Table 3.3 indicates how scientists who
are worried about funding and publications, extension staff needing to cover
their district with limited budget and time, and farmers who are concerned
with crop prices and too much or too little rain might benefit from a working
group routine based on participatory learning for action. Each plays an ample
role in the advance of weed management; each has expectations to meet and
procedures to follow in their own knowledge communities; and each has
opportunities for creative working relationships with other sectors.
Farmer communication with other farmers
In Europe and the USA and especially in Latin America, Africa, and
Asia, there are many, many more farmers than extensionists, and many more
extension agents than scientists. With these proportions, how can participa-