Improved retention of a soil fumigant during solid tarp application

Authors: Chellemi, Daniel; UNRUH, BRYAN - UNIVERSITY OF FLORIDA; MIRUSSO, JOHN - MIRUSSO ENTERPRISES

Submitted to: Proceedings of International Research Conference on Methyl Bromide Alternatives
Publication Type: Proceedings
Publication Acceptance Date: 10/1/2009
Publication Date: 11/11/2009
Citation: Chellemi, D.O., Unruh, B., Mirusso, J. 2009. Improved retention of a soil fumigant during solid tarp application. Proceedings of International Research Conference on Methyl Bromide Alternatives.

Interpretive Summary: A field trial was conducted in Fort Pierce, Florida in cooperation with a commercial sod producer to investigate ways to improve the retention of soil fumigants during solid-tarp (broadcast) applications. A 2 x 2 x 2 factorial experiment was conducted examining the individual and combined effects of soil preparation (cultivated vs sealed), application equipment (shanked vs low disturbance vertical coulters) and plastic permeability (LDPE vs VIF). Qualitative estimates of fumigant concentrations in the soil atmosphere following application were obtained using a hand held portable volatile organic compound meter (MiniRae 2000). Quantitative estimates were obtained by gas chromatograph/mass spectrometer analysis of 500 ml of soil air samples collected using Amberlite XAD-4 tube glass filters. Both soil air samples were collected at 0-5 inch depths. Quantitative estimates of fumigant concentrations in soil were obtained by gas chromatograph/mass spectrometer analysis of soil samples collected at 0.5 inch, 2.5 inch and 4.5 inch depths. A second field trial was conducted to examine soil retention of 1,3-dichloropropene applied at various rates using optimum fumigation practices that included sealing the soil surface with a roller, minimizing soil disturbance during application through the use of a low disturbance vertical coulter application equipment, and immediately covering treated soil with a virtually impermeable film. Five days after application, significant interactions between soil preparation and application equipment and between application equipment and plastic type on the retention of 1,3-dichloropropene in soil were observed (Table 1). Ten days after application, both equipment and plastic type had a significant effect on fumigant retention. The lowest soil concentration of 1,3-dichloropropene was observed when the fumigant was shank applied into cultivated soil and covered by LDPE (Table 2). The results indicate that retention of fumigants in soil during solid-tarp applications can be improved using various combinations of improved application practices

Technical Abstract: A field trial was conducted in Fort Pierce, Florida in cooperation with a commercial sod producer to investigate ways to improve the retention of soil fumigants during solid-tarp (broadcast) applications. A 2 x 2 x 2 factorial experiment was conducted examining the individual and combined effects of soil preparation (cultivated vs sealed), application equipment (shanked vs low disturbance vertical coulters) and plastic permeability (LDPE vs VIF). Qualitative estimates of fumigant concentrations in the soil atmosphere following application were obtained using a hand held portable volatile organic compound meter (MiniRae 2000). Quantitative estimates were obtained by gas chromatograph/mass spectrometer analysis of 500 ml of soil air samples collected using Amberlite XAD-4 tube glass filters. Both soil air samples were collected at 0-5 inch depths. Quantitative estimates of fumigant concentrations in soil were obtained by gas chromatograph/mass spectrometer analysis of soil samples collected at 0.5 inch, 2.5 inch and 4.5 inch depths. A second field trial was conducted to examine soil retention of 1,3-dichloropropene applied at various rates using optimum fumigation practices that included sealing the soil surface with a roller, minimizing soil disturbance during application through the use of a low disturbance vertical coulter application equipment, and immediately covering treated soil with a virtually impermeable film. Five days after application, significant interactions between soil preparation and application equipment and between application equipment and plastic type on the retention of 1,3-dichloropropene in soil were observed (Table 1). Ten days after application, both equipment and plastic type had a significant effect on fumigant retention. The lowest soil concentration of 1,3-dichloropropene was observed when the fumigant was shank applied into cultivated soil and covered by LDPE (Table 2). The results indicate that retention of fumigants in soil during solid-tarp applications can be improved using various combinations of improved application practices