DEAD ZONE: Runoff from Midwest farms plagues Gulf By Perry Beeman Gannett, theNewsStar.com3 November 2012 CHAUVIN — For shrimpers, crabbers and oystermen who work these waters, locating their harvest has become an increasingly taxing game of hide-and-seek. Nitrates from the fertilizer and manure that Iowa's farmers apply to their fields, mixed with sewage and runoff [...]