|Lerch, Robert - Bob|
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 8/9/2005
Publication Date: 9/27/2005
Citation: Lin, C., Lerch, R.N., Garrett, H.E., Gantzer, C.J., Anderson, S.H., George, M.M. 2005. Evaluating effectiveness of three grass buffer designs in reducing atrazine, metolachlor and glyphosate transport in surface runoff. ASA-CSSA-SSSA Annual Meeting Abstracts. Interpretive Summary:
Technical Abstract: Multiple species riparian grass buffers have been recommended as a cost-effective approach to mitigate herbicide transport in surface runoff derived from agronomic operations. However, the effectiveness of different buffer designs, such as species selection, combinations of different species, and buffer length, on reductions in herbicide transport have not been well documented. An experiment consisting of three grass buffer designs and one cultivated fallow control with three replications was conducted to assess effectiveness in reducing herbicide transport for claypan soils. The four vegetative filter strip treatments include: 1) tall fescue, 2) switchgrass hedge in combination with tall fescue, 3) switchgrass hedge in combination with native grass and forbs species, and 4) continuous cultivated fallow as a control. Rainfall simulation was used to create uniform antecedent soil moisture content in the plots and to generate runoff. Runoff collection equipment was installed at 1 m above the buffers and within the buffers at 1, 4, and 8 m below the upslope end. Grass buffers significantly reduced the transport of atrazine, metolachlor and glyphosate in surface runoff. Grass buffers with native species were most consistently effective at reducing herbicide transport. The 8-m native species buffers removed 75-80% of the atrazine, metolachlor and glyphosate in surface runoff. Four meters of native species buffer resulted in similar or equivalent reductions in transport of atrazine and metolachlor as eight meters of tall fescue buffer. Thus, the implementation of native species buffers could provide desired reductions in herbicide transport with less land taken out of production.