In contrast to respiration data, to

In contrast to respiration data, total microbial biomass measured by the sum of EL-FAMEs did not respond to Glyphosate addition, nor was there any consistent pattern of individual EL-FAME responses to glyphosate over the course of the incubation. The initial microbial biomass of these three soils, as measured by total extractable EL-FAME, was not significantly different (data not shown). These results are consistent with other studies that observed changes in microbial activity upon glyphosate exposure, but were unable to characterize long term shifts in microbial communities due to glyphosate, by using fatty acid analysis (Busse et al., 2001, Ratcliff et al., 2006, Weaver et al., 2007, Lancaster et al., 2010 and Lane et al., 2012). Weaver et al. (2007) did find small, short lived changes in microbial communities after glyphosate application. However, these changes lasted less than seven days. A transient suppression of general bacterial and fungal phospholipid fatty acids after glyphosate application to forest soils was found in a study by Ratcliff et al. (2006). However, this suppression lasted 1–3 days. Our study sampled soils 15 days after the first application, and 30 days after the first, second, fourth, fifth, and sixth