IPM Assessment and Risk:Framing the Issues and Vocabulary

Scott M. Swinton

Dept. of Agricultural Economics

Michigan State University

4th National IPM Symposium, Indianapolis, Apr. 8-10, 2003

“Assessment” for what purpose?

• To motivate adoption of IPM methods

• To evaluate the effects of investments in IPM

Assessment to motivate adoption

• Motivation programs aim to encourage by– Showing that goal is do-able– Rewarding progress

• Industry-driven scoring systems of IPM assess to motivate adoption– Lots of points, so everyone feels successful– No negative points

IPM point scoring system: Mass. IPM Guidelines for Potato

• Crop rotation 20• Cover crop 10• Sprayer calibrated 10• Bt ½ insect spray 15• Attended workshop 5• Owns veg mgt guide 10• ……..

• 320 POINTS IN ALL– Pest, soil/water & education

categories for points

• Used for certification• Program assessment

questions:– How much IPM is 180

of 320 points?– Do all combinations of

180 points have same effect on pesticide use? Net income?

Source: C. Hollingsworth et al. (1996)

Assessment to evaluate programs

• Evaluations seek to determine– Progress toward specific goals– Measurement of program net benefits

• Public program assessments– Need clear, simple IPM definitions– Should be impartial– Can be threatening to those engaged in programs– Feedback permits learning about what works and

what doesn’t, leading to better use of public funds

Risk in IPM assessment

• Risk matters in all IPM dimensions– Profitability– Health– Environmental

• “Risk” can refer to – Danger (in an average sense)– Probability of undesired outcome

“Risk” as a danger

• “There’s a 2% risk of a damaging pest infestation.”– 2% is a mean point estimate of danger– Many factors affect probability of pest

infestation

0 2% 4% 6%

“Risk” in probabilistic sense

• “Biological control may increase risk of damaging pest infestation.”– Refers to dispersion of probability

distribution (from Pa to Pb)

0 2% 4% 6%

Pb

PaNote: Mean of Pa = mean of Pb = 2%

Avoiding Tower of Babel

• Let’s be clear about intent in referring to “risk” and “assessment”

• What about definitions of IPM?Even more clarity needed!