Pest Identification and Biology of Turf and Ornamental Pests
Domain 1 tests whether you can identify a pest and explain its biology well enough to choose a tactic that targets the vulnerable stage. Florida's Lawn and Ornamental exam emphasizes species common in turf and landscapes: southern chinch bug, fall armyworm, tropical sod webworm, mole crickets, hunting billbug, white grubs, plant-parasitic nematodes, scales, whiteflies, thrips, aphids, mites, and palm pests. Identification means more than naming an insect; you must link the damage pattern to a feeding guild and life cycle.
Feeding guild narrows the diagnosis
Chewing insects remove tissue: caterpillars leave notched blades, window-paning, and frass; beetles and weevils chew stems or roots. Piercing-sucking insects remove sap: chinch bugs, aphids, scales, whiteflies, mealybugs, spittlebugs, and mites cause yellowing, stunting, honeydew, sooty mold, or distorted new growth. Root feeders - mole crickets, white grubs, billbugs, and nematodes - cause thinning and poor recovery because roots are severed.
Life cycle sets the timing
Most turf caterpillars damage as larvae; moths flying over the lawn are adults and are not the target. Southern chinch bug nymphs are red-orange and feed in the thatch and lower stems; adults are small, black, and white-winged. Mole crickets are soil-dwelling; baits work best in the evening when they forage. Scales are most vulnerable as crawlers. Treating the wrong stage wastes product and selects for resistance.
Florida specifics
Southern chinch bug (Blissus insularis) is the key St. Augustine pest, especially in full sun and drought stress; a commonly cited action threshold is about 20–25 nymphs per square foot. Tropical sod webworm and fall armyworm are late-summer and fall caterpillars. Tawny mole cricket causes the most turf damage among Florida's mole crickets; Steinernema scapterisci nematodes are a biological option. In ornamentals, watch for cycad aulacaspis scale, lobate lac scale, ficus whitefly, rugose spiraling whitefly, and broad mite on new growth.
Worked example
A St. Augustine lawn in full sun shows spreading yellow patches along a driveway. You part the turf and find red-orange nymphs and black-white adults in the thatch; blades are not notched, and there is no frass. That points to chinch bug, not sod webworm or drought. Because nymphs cause most damage, you treat the nymph stage with a labeled product, water before treatment if the lawn is drought-stressed, and recheck in 7–10 days.
Traps that cost marks
Do not call every yellow patch a disease or every chewed blade a chinch bug. Do not treat adult moths. Do not confuse beneficial insects with pests, and do not overlook that dead, brown turf can be caused by disease, fertilizer burn, or drought rather than an insect.