Abstract
Granulated bait formulations of Amdro, Award, and (S)-Methoprene were applied to individual RIFA mounds on 28 Aug 1996 in Collin Co., TX. Applications were applied to each mound individually with a hand-held shaker to distribute the bait evenly over an area ca. 3 ft in diam with the mound in the center. Plot size ranged from 300-500 ft2, each with 3 to 5 (mean = 3.7) active colonies. Plots were delineated with white turf marking paint; each colony within a plot was identified by numbers painted on the turf ca. 1.5 ft from the mound. Pre-treatment foraging activity was assayed by placing 3, 8-dram shell vial traps, baited with hot dog chips, near the center of each plot and no closer than 3 ft from an active colony. Vials were collected with RIFA foragers counted after 30 min exposure. Plots were divided into 4 replicates based on pre-treatment foraging numbers. RIFA foraging activity was assessed at 1, 2, 3, 5, and 7 wk after treatment (WAT). Individual mound mortality was determined at 1, 3, 5, and 7 WAT by stomping hard (4-5 times) on the soil or turf in a 1-ft circle around each mound. Upon disturbance, an active mound would yield many active workers. For rating at 4 and 6 wk, a hot dog chip was dropped upon the mound and observed 20-30 min later. If the colony was active, workers would forage the hot dog piece within this time period.
Do Mound Disturbance and Bait Placement Affect Bait Removal and Treatment Efficacy in Red Imported Fire ant (Hymenoptera: Formicidae) at Different Seasons?