The Collaborative International Dictionary of English v.0.48:

Chess \Chess\, n. (Bot.)
   A species of brome grass (Bromus secalinus) which is a
   troublesome weed in wheat fields, and is often erroneously
   regarded as degenerate or changed wheat; it bears a very
   slight resemblance to oats, and if reaped and ground up with
   wheat, so as to be used for food, is said to produce narcotic
   effects; -- called also cheat and Willard's bromus. [U.
   S.]
   [1913 Webster]

   Note: Other species of brome grass are called upright
         chess, soft chess, etc.
         [1913 Webster]