Pest Identification and Management
Know the pest before you treat it
Every management decision starts with correct identification. Learn to distinguish insects from mites, weeds from desirable plants at the seedling stage, and diseases from abiotic injury (nutrient deficiency, herbicide drift, frost, drought). Questions often describe symptoms and ask for the cause; a key trap is confusing insect feeding damage (chewed edges, holes, stippling) with disease lesions (spots with halos, wilting, rot) or with abiotic stress that shows uniform patterns across a field.
Concepts to master
- Life cycles and metamorphosis: understand egg, nymph/larva, pupa, adult stages, because the stage most vulnerable to a pesticide differs by pest. Soft-bodied nymphs are easier to control than hard-shelled adults.
- Economic threshold and action threshold: treat only when pest numbers justify it. Questions test the difference between the threshold (the decision point) and economic injury level.
- Integrated Pest Management (IPM): combine cultural, mechanical, biological, and chemical controls; pesticides are one tool, not the first resort.
- Beneficials and resistance: recognize predators and pollinators, and understand that repeated use of one mode of action selects for resistance.
Traps
Watch for questions implying calendar-based spraying is best (it is not), or that the largest pest count always warrants treatment (thresholds matter). Distinguish "monitoring" (scouting) from "control."
Rule of thumb
Scout, identify, compare to threshold, then choose the least-risk effective tactic. If you cannot name the pest, you cannot responsibly choose a product.