Knowledge, science, and practice in ecological weed management: farmer–extensionist–scientist interactions - Ecological Management of Agricultural Weeds - page 127

mentation groups have formed their own umbrella organization to find
funding and provide technical advice (Ashby et al ., 1999). What are the essen-
tial components for a vitalized co-learning network that encompasses
research, public and private extension, and formal and informal farmer to
farmer communication? The answer will depend on the experiences gener-
ated in such diverse areas as California, Iowa, Holland, Peru, Cuba, Vietnam,
Philippines, Senegal, and many other countries (Thrupp, 1996; Veldhuizen et
al ., 1997).
Farmers, extensionists, and scientists learning together:
four examples
The case studies described in the following pages represent a spec-
trum of farmer-extensionist-scientist collaboration to improve weed man-
agement and crop production. The first case describes a study controlled
primarily by scientists, whereas the last case describes a farmer-to-farmer
approach.The cases complement one another in illustrating the four concepts
of participatory learning described previously.Each case is innovative in some
dimension. However, in all the cases widespread improvement of farmer
capacity for ecological weed management remains a challenge.
California tomato cropping systems: farmers advise a research
station study
In the late 1980s a group of scientists representing ten different disci-
plines at the University of California at Davis established a 12-year replicated
comparison of conventional, low-input, and organic tomato-based cropping
systems [see Temple et al .(1994 a ,1994 b ) for details of treatments and working
procedures]. Tomato is one of the most economically important crops in the
state. The group decided to work on the experiment station to insure rigor in
the operation of the experiment and in data collection. However, they were
also interested in using best farmer practices in each system to achieve profit-
ability rather than comparing predetermined fixed treatments. They
recruited an advisory committee of two conventional and two organic tomato
growers and two county extension advisors. Farmers, extension advisors, and
scientists have been meeting every two weeks to analyze the status of the
experiment and to plan upcoming crop management activities.
This California case is innovative in its multidisciplinary focus, in the
treatment flexibility based on the use of best farmer practices, and in the
incorporation of farmers as advisors. A comparison with the concepts of par-
ticipatory learning for action suggests that learning was done primarily on the