Integrated Pest Management Principles and Resistance Management
Domain 7 tests IPM as a decision process, not a slogan, and resistance management as a biological and legal necessity. Expect questions on monitoring, thresholds, cultural and biological controls, spot treatment, and rotating modes of action.
The IPM sequence
Identify the pest or disorder; monitor with flushes, soapy water, traps, or visual counts; compare to a threshold; choose the least disruptive effective tactic; evaluate. For chinch bug, a commonly cited threshold is about 20–25 nymphs per square foot. For white grubs, treat when grubs are present and turf can no longer recover; for sod webworm, spot-treat hot spots rather than the whole lawn.
Cultural and biological tactics
Resistant or tolerant cultivars, proper mowing height, sharp blades, deep infrequent irrigation, thatch control, and balanced fertility reduce pest pressure. Conserve predators and parasitoids; use Bt for caterpillars, Steinernema scapterisci for mole crickets, and predatory mites where appropriate. Avoid broad-spectrum sprays that flare mites, scales, and whiteflies.
Resistance management
Rotate IRAC, FRAC, and HRAC groups; use full labeled rates; limit the number of applications per season; tank-mix products with different modes of action when the label allows; and do not repeat the same MOA against consecutive generations. Florida has documented pyrethroid resistance in southern chinch bug and resistance issues in fall armyworm and whitefly, so product choice matters.
Worked example
A bermuda lawn has scattered sod webworm damage on 10% of the area. Monitoring finds larvae under a soapy-water flush, but the damage is below the treatment threshold. The IPM response is to spot-treat the hot spots, mow and irrigate properly, and recheck in a week - not to spray the entire lawn with a pyrethroid.
Traps that cost marks
Do not spray on a calendar. Do not rotate between two products with the same MOA. Do not assume organic or biological products cannot select for resistance. Do not overfertilize; lush growth increases chinch bug, aphid, and mite pressure.