Knowledge, science, and practice in ecological weed management: farmer–extensionist–scientist interactions - Ecological Management of Agricultural Weeds - page 103

1843 Lawes and Gilbert, among the earliest proponents of the scientific
method in agriculture, set up the first of their field experiments in
Rothamsted (Johnston, 1994). Early agricultural scientists studied the effec-
tiveness of mechanical weed control, rotations, and cover crops (Karlen et al .,
1994). These concepts had been developed by farmers centuries earlier, and
much of the early scientific agronomic knowledge was drawn from farmer
practice.
The advent of the experiment station and the agricultural scientist
brought about an important change in the development and spread of crop
production technology. Whereas previously farmers were both the principal
generators and users of technology, with the development of formal experi-
mental science, a large proportion of technology generation moved off-farm.
Thus, the generators and the users of technology separated into two different
sectors (Busch & Lacy, 1983, pp. 5-36). Initially experiment stations main-
tained close links to the farm sector. However, with the emergence of disci-
plines within agricultural science, scientists distanced themselves from
regular contact with farmers.They developed professional networks and jour-
nals to systematically document their work for their own use (Lockeretz &
Anderson, 1993, pp. 26-7). In 1914 in the USA the separation in the genera-
tion and use of crop production technology was formally addressed through
the establishment of the cooperative extension service under the Smith-Lever
Act.
The development of herbicides, beginning in 1896 in a French vineyard
with the chance discovery of the selective effects of copper sulfate on plants,
further altered the relationship between weed technology generation and use.
Advances in the laboratory sciences of chemistry and plant physiology led to
the near simultaneous discovery in USA, England, and France of hormonal
herbicides in the 1940s. This technological innovation was made with no
input from farmers.Although farmers now have the choice of hundreds of dif-
ferent herbicides for a wide variety of crops, weed control has become a con-
sumable, off-farm input in crop production. Herbicides must be purchased
for each crop cycle. The separation between technology generation and use in
the case of herbicides has been addressed by the public extension service, field
sales representatives, and private crop consultants.
Farmers' intuitive understanding of weed ecology has formed part of crop
production technology from the beginnings of agriculture. However, formal
studies in weed ecology originated just in the past 50-75 years. Studies in
weed ecology have only recently begun to affect the development of technolo-
gies for weed management. These studies have focused on the minimum
weed-free period for different crops, the crop loss effects of different weed