Sprayed to Death: Why Farmers Won”t Switch to Safer Pest Control

Agricultural pests can be controlled in a way that avoids blanket spraying of the chemical pesticides that pollute our groundwater and leave residues in our food. The techniques of 'Integrated Pest Management' (IPM) are just as effective and inexpensive as pesticides; and they don't endanger our health. But without government intervention, farmers won''t make the change because they are locked into the benefits of their current technology and can't face the uncertainty and costs of learning and new equipment involved in making a switch. That is the conclusion of Robin Cowan and Philip Gunby in an article published in the May 1996 issue of the Economic Journal.

Cowan and Gunby describe how, using IPM, a farmer may tackle the insects, weeds and diseases that threaten his crops. For example, he may breed and release natural predators to kill the pests or use crop rotation to deny them a stable source of food. Importantly, IPM emphasises that decisions on control measures be taken on the basis of economic rather than physical damage.

IPM techniques have not been widely used to date. Nevertheless, detailed case studies of the Israeli citrus fruit industry and the cotton industry in Texas show that when the approach is well developed and widely adopted, it can provide high quality crops at costs to the farmer as low as (and in some cases lower than) those of chemical pesticides.

The case studies also indicate that, left to itself, the market will not generate a move from the dominant but inferior technology of chemical treatment to IPM. The agricultural industry seems to be locked into the use of pesticides. Cowan and Gunby discern four mechanisms that allow this to happen:

  • Global learning: farmers' understanding of the properties of chemicals, sprayer nozzle designs, etc.; and their need to learn about the predators of insect pests, insect life cycles and their interactions with crop rotations.
  • Localized learning: knowing spray schedules and dosages; in contrast with having to learn
    about scouting for pests, identifying them and their predators, and calculation of the economic costs of pest damage versus the costs of damage prevention.
  • Specialized equipment: already owning sprayers and manufacturing technologies for chemicals; versus acquiring insectiaries for breeding predators, techniques and equipment for their release, and/or the design of pheromone traps.
  • Uncertainty: an old technology will be well understood and its payoffs predictable; this is not the case with a new one until considerable experience has been accumulated, until which time it will be perceived as risky. Anyone concerned with risks will have a disincentive to switch to the new technology.

These features lead to a snowball effect in farmers'' choice of technology. Any heavily adopted technology is well-placed in terms of each feature, and so has a higher net benefit from use. With a higher benefit, more farmers are likely to adopt it, which contributes further to its benefits. This makes it very difficult to switch from one technology to the other: even if everyone gains from a universal switch from chemical controls to IPM, no one is willing to be the first. And, naturally, it is difficult to coordinate a switch among so many parties.

Cowan and Gunby suggest that it may be possible for government intervention to be effective in such a situation. Governments could subsidize the learning necessary to develop an IPM programme or, if one already exists, they could provide a coordination device by which farmers switch en masse from one technology to the other.

In this context, since government budgets are shrinking, geographically focused intervention may provide the key, enabling the development of locally effective IPM programs, and making it possible for all farmers in an area to switch to them. Under the right conditions and policies, both farmers and consumers could be made better off by a switch to a different approach to pest control.

'Sprayed to Death: Path Dependence, Lock-in and Pest Control Strategies' by Robin Cowan and Philip Gunby is published in the May 1996 issue of the Economic Journal. Cowan is Assistant Professor of Economics at the University of Western Ontario, Canada. Gunby is Assistant Professor of Economics at the University of Canterbury, Christchurch, New Zealand.