Today’s USDA quarterly Grain Stocks report provided the market with a bullish input but there may be another shoe to drop. Russia’s stocks to use ratio for corn and wheat have been dropping for four straight years. Over that timeframe, it is down 64 percent for corn and 48 percent for wheat. Russia has continued to export wheat at low prices despite the tightening supply, but it has increased the export duty on corn by ten-fold, to 2,786.2 rubles ($30)/MT.  Russia has exported aggressively to both earn foreign exchange and build respect from food insecure nations. However, Moscow has concluded that at least when it comes to corn, it needs to cover its own food security needs and prevent domestic food inflation. But wheat a...