Integrated Pest Management, or IPM, is a science-based approach to controlling pests while reducing harm to people, ecosystems, and beneficial organisms. This cheat sheet helps students organize the major steps of IPM, from identifying a pest to choosing the least harmful effective control. It is useful in environmental science because pest control affects food production, biodiversity, water quality, and human health.
Students need to understand that IPM is not just pesticide use, but a decision-making system.
The core ideas of IPM are prevention, monitoring, correct identification, action thresholds, and a mix of control strategies. Control methods can include cultural, mechanical, biological, and chemical controls, often used together. A key rule is to act only when pest damage is likely to exceed an acceptable level, rather than trying to eliminate every pest.
The best IPM plans reduce pest populations while slowing pesticide resistance and protecting non-target species.
Key Facts
- Integrated Pest Management uses prevention, monitoring, identification, thresholds, and targeted control to manage pests with the least overall harm.
- A pest is any organism that harms human interests, crops, buildings, health, or native ecosystems in a specific situation.
- Correct pest identification is required because different species may need different controls and some look-alike organisms are beneficial.
- An action threshold is the pest population level or damage level at which control should begin to prevent unacceptable loss.
- Economic injury level means the pest damage cost equals the control cost, so control is justified when expected damage is greater than treatment cost.
- Cultural control changes the environment or farming practice, such as crop rotation, sanitation, resistant varieties, or adjusted planting dates.
- Biological control uses natural enemies such as predators, parasites, pathogens, or competitors to reduce pest populations.
- Pesticide resistance increases when the same pesticide or mode of action is used repeatedly, because resistant individuals survive and reproduce.
Vocabulary
- Integrated Pest Management
- A planned pest control approach that combines monitoring, prevention, and multiple control methods to reduce pests with minimal environmental harm.
- Action Threshold
- The pest level or damage level at which taking control action becomes necessary to prevent unacceptable harm.
- Biological Control
- The use of living organisms, such as predators, parasites, or pathogens, to reduce a pest population.
- Cultural Control
- A pest management method that changes human practices or habitat conditions to make pest survival or reproduction less likely.
- Selective Pesticide
- A pesticide designed to affect a narrow range of target pests while causing less harm to non-target organisms.
- Pesticide Resistance
- An inherited ability of some pests to survive a pesticide that would normally kill members of that species.
Common Mistakes to Avoid
- Treating any insect as a pest is wrong because many insects are pollinators, decomposers, predators, or harmless species.
- Spraying before monitoring is wrong because IPM requires evidence that the pest is present and near or above the action threshold.
- Using the strongest pesticide first is wrong because it can kill beneficial organisms, contaminate the environment, and speed up resistance.
- Ignoring non-chemical controls is wrong because sanitation, barriers, crop rotation, and biological control can prevent pests before chemicals are needed.
- Repeating the same pesticide every time is wrong because it selects for resistant pests and can make future outbreaks harder to manage.
Practice Questions
- 1 A greenhouse manager finds 12 aphids per plant, and the action threshold is 20 aphids per plant. Should chemical control begin now based only on this threshold, and why?
- 2 A farmer estimates that an insect outbreak will cause 650. Based on economic reasoning, is treatment justified?
- 3 In a field of 100 plants, 18 show pest damage. What percentage of plants are damaged?
- 4 Explain why an IPM plan might use crop rotation, insect traps, lady beetles, and a selective pesticide instead of relying on one broad-spectrum pesticide.