Allegheny Mound ant Control with Sevin and Malathion, Wv, 1994

Abstract

The study was conducted in a sparsely wooded area pastured to cattle and contained about 50 mounds per ha. Ant mounds were categorized for treatment by diam size as small (up to 1.11 m), medium (1.14 to 1.40 m) and large (½ than 1.40 m). Mounds were prepared for treatment by scraping off (with a hand trowel) the top of each mound to expose the large passage tunnels; amount of top removed on small, medium, and large mounds, respectively, was 20 to 25 cm, 30 to 35 cm, and 30 to 45 cm. The number of mounds treated with each compound included 3 small, 3 medium, and 3 large mounds; a similar number of untreated mounds were marked as checks for natural mortality. The amount of drench solution applied to the exposed scrape surface of each mound was 1, 2, and 3 liters for small, medium, and large mounds, respectively. Drenches were applied with a sprinkling can. Rates for mixing solutions (% AI) for Sevin and Malathion were similar to those recommended for fire ant control. Treatments were applied 28 Jul. Treatment efficacy was evaluated at about 2 wk intervals by excavating (with a hand trowel) a small opening into the undisturbed side of mounds and observing the responding activity of ants to this disturbed area. A mound was judged active or inactive depending on the presence or absence of ants at the excavation site. Air temperature and RH at the start and finish times of treatment were 20°C and 26°C, and 70% and 61%, respectively; partly cloudy. Accumulative precipitation at 15, 29, 43, and 56 DAT was 4.1, 16.3, 16.8, and 17.8 cm, respectively. Final evaluations (56 DAT) were made by excavating 1/3 to 1/2 of each mound down to ground level to check for ant activity.