Our local paper reported a “crop failure” for “Kernza”, a much-touted “perennial grain.”  A 2013 paper in Agronomy Journal reported first-year yields of 156 kg/ha for Kernza versus 3761 kg/ha for annual wheat (both with organic management).  Second-year yields were 1390 versus 4460 kg/ha and when I visited the site I was told that Kernza went downhill after that.    This is consistent with the hypothesis in my book, that there are major tradeoffs between perenniality and grain yield.  Perennials are great for controlling erosion, though, so maybe we should grow annual grains on less-erodible soils and perennial forages on slopes.