“…In contrast, the geochemical signature of groundwater beneath turfgrass in residential lawns has not been determined in this region. Furthermore, studies of nitrate loss from turfgrass management often involve controlled field experiments with vadose-zone monitoring (e.g., Easton and Petrovic, 2004;Frank et al, 2006;Frank, 2008;Geron et al, 1993;Guertal and Howe, 2012;Guillard and Kopp, 2004;Mangiafico and Guillard, 2006;Morton et al, 1988). Survey data, however, suggest that actual suburban fertilizer usage may not be well represented by controlled studies and can be highly variable (Law et al, 2004).…”