Abstract Two acaricide tests were applied to cotton, planted 6 Apr (Shafter, Calif.) and 15 Apr (Five Points, Calif.) with individual plots 16 (Shafter) or 8 (Five Points) rows wide by 150 ft long and replicated 4 times in a randomized complete block design. Application was by high-clearance ground sprayer equipped with drop booms using 5 TX-6 (Shafter) or 7 TX-3 (Five Points) hollow-cone nozzles/row, both delivering 25 gal/ acre at 40 psi and 3 mph or 30 psi and 4 mph, respectively. The Shafter test was applied 24 Jun; the Five Points test was applied 9 Jul. An overall application of Monitor 4 EC at 0.5 lb (AI)/acre was made at the Shafter test by ground on 16 Jun to suppress Lygus hesperus and predators. At Five Points, Orthene 75 S at 0.33 lb (AI)/acre was applied over all on 29 Jun to suppress predators. Main stem leaves (25/plot, eighth unfolded leaf below main stem terminal) were sampled 4 times after acaricide treatment and processed through a sodium hypochlorite wash system. Counts of all motile mites were analyzed by ANOVA, and means were separated by LSD.