Control of [the American dog tick] Dermacentor variabilis. 3. An analytical study of the effect of low volume spray frequency on insecticide-stressed and nonstressed populations [Rocky Mountain spotted fever]

• Published in: Journal of the New York Entomological Society 1981-01, Vol.89 (1), p.23-33
• Main Authors: White, D.J, Benach, J.L, Smith, L.A, Ouyang, S.P
• Format: Article
• Language: English
• Subjects: Data analysis; Depopulation; Dogs; Entomology; Habitat preferences; Insecticides; Population estimates; Rocky Mountain spotted fever; Ticks; Vegetation; Water treatment
• ISSN: 0028-7199; 1937-2361

Nine field plots (each 0.4-0.6 ha) were selected along the south central part of Long Island, New York, to study the effect of insecticide spray frequency on a questing Dermacentor variabilis population. Assignment of treatment was made according to dominant vegetation, location and tick preferential habitat. Three plots received no treatment, 3 plots were sprayed with water (3 once, 2 twice, and one 3 times) and 3 plots were similarly sprayed with an emulsifiable formulation of naled. Plots were randomly monitored for tick density at weekly intervals. A total of 2,872 ticks was collected from all plots by dragging. Multiple and simple regression and exploratory data analyses were employed to determine normal or estimated tick populations at each plot throughout the adult tick season, rate of seasonal weekly decline of tick population, and the effect of insecticide spray frequency on the questing American dog tick population. Results indicated a 20% weekly exponential decay in numbers of questing adult ticks over the 1978 season. No effect was seen due to the water treatment. One spray of naled produced an 82% reduction of the questing tick population; 2 sprays, a 95% reduction; and 3 sprays, a 96% population reduction.