Synthetic Pyrethroid Dusts Evaluated for Individual Mound Control of Red Imported Fire ant in Residential Landscapes, 1995

Abstract

Dust formulations of two synthetic pyrethroid were applied to individual mounds of RIFA in residential turf on 13 Nov, 1995 in Dallas, TX. Material was applied with a hand held shaker evenly over the mound or to the mound and including a 6 inch perimeter area around the mound. Mounds treated with either Tempo or Orthene that were still active at the 1-wk rating, were retreated at their initial rates. Orthene 75%S was used as the standard control and both a water check (1 gal of water sprinkled over each mound) and an untreated check were included. All treatments were replicated on 12 isolated mounds. Mound activity was assessed the day before treatments and 3-d, 1-wk, and 2-wk posttreatment ratings were taken. Mound activity was determined by stomping hard (4-5 times) on the soil or turf ca 1 ft from the mound in a circle around each mound. For the final rating at 2 wk, each colony was also excavated to a depth of ca. 8 inches with a small shovel to determine mound activity. If no live ants were found, the colony was considered dead. The percentage mortality provided by each chemical treatment was determined and the means were separated using exact confidence intervals calculated from binomial distribution (Steel & Torrie. 1960. Principles and Procedures of Statistics. McGraw-Hill Book Co., Inc.).