> Twenty 50-m trail segments across two sites were randomly assigned to intervention groups: untreated woodchip borders, deltamethrin-treated woodchip borders, and ten assigned to untreated controls.

> Treated woodchips reduced I. scapularis adult and nymph density by 99 % (incidence rate ratio (IRR) = 0.01, 95 % CI: 0.001–0.08) relative to controls, while untreated woodchips achieved a 48 % reduction (IRR = 0.52, 95 % CI: 0.34–0.78).