Pesticide Decay in Turf: A Review of Processes and Experimental Data

Abstract

Decay rates are central parameters in modeling pesticide fate and transport in the environment. Pesticide decay is usually modeled as a first-order process, and variations in half-life can have significant impacts on model predictions. Decay rates for the foliage and thatch components of turf are scarce, and most simulation efforts must resort to values based on pesticide behavior in soil. This paper describes the main dissipation processes affecting pesticides applied to turf and compares aerobic soil decay rates from the USDA-Agricultural Research Service Pesticide Properties Database (ARS PPD; USDA-ARS, 2006) and from The Pesticide Manual (Tomlin, 2003) to dissipation values in turf found in the literature for 18 pesticides currently registered for turf. Median half-lives were 39.5 d for the ARS values, 35.8 d for Tomlin's values, and 5.7 d for the turf-specific values. The turf dissipation half-lives are considered to be representative of the microbial decay processes occurring in the foliage and thatch layers of well established turf, where the majority of the pesticide is intercepted and retained.

Residual Efficacy of Fungicides for Controlling Brown Patch on Creeping Bentgrass Fairways

“…Flutolanil experiments initiated in June had much shorter residual efficacy compared with experiments conducted later during the growing season. Given that all samples were incubated under the same environmental conditions, inconsistency among flutolanil results is likely due to variation degradation processes in the field (8,10,16,17,(20)(21)(22)(23). However, specific degradation factors responsible for the observed differences with regard to flutolanil residual efficacy among experiments are not known.…”

“…Depletion of fungicide residues can result from runoff and leaching during rainfall or irrigation events, volatilization, removal of clippings during mowing, photolysis, microbial degradation, and enzymatic breakdown in the plant (8,10,16,17,(20)(21)(22)(23). Fungicide depletion is a concern because it exposes turfgrass to the possibility of brown patch outbreaks during periods of weather that favor pathogen development.…”

Chiral Analysis of Pesticides and Drugs of Environmental Concern: Biodegradation and Enantiomeric Fraction

“…Application of pesticides is a worldwide and of utmost importance for current agricultural productivity standards and the control of vectors and pests of public health relevance [60]. The dissipation rate of a pesticide into the environment is the primary indicator to its environmental fate [61]; these concepts are further explained in a recent review work [62]. Applied pesticides in agricultural fields affect the surrounding environmental compartments at four major levels: (i) air, through volatilization and wind action; (ii) soil, through direct application and run-off; (iii) surface waters, through run-off and via drainage systems; and (iv) ground water, via leaching and preferred water flow [62][63][64].…”

Residual Efficacy of Insecticides Applied to Exterior Building Material Surfaces for Control of Nuisance Infestations of <I>Megacopta cribraria</I> (Hemiptera: Plataspidae)

“…Panels in our study were shielded from rain and direct sunlight to avoid complications from variable weather conditions. Both of these factors play a role in pesticide residue breakdown (Konstantinou et al 2001, Magri andHaith 2009), and would likely shorten the activity of insecticides applied to homes or other structures. However, the controlled environmental conditions of our experiment allowed for separation among the treatment combinations, providing baseline information on their potential durability in practical applications.…”