plot    variety     bushels

                          1     Agrigrow      57.1 
                          2     Agrigrow      55.8 
                          3     Agrigrow      55.0 
                          4     Agrigrow      56.3 
                          5     Bennyjet      54.5 
                          6     Bennyjet      53.8 
                          7     Bennyjet      55.3 
                          8     Bennyjet      55.8 
                          9     Columbia      56.5 
                         10     Columbia      57.9 
                         11     Columbia      55.0 
                         12     Columbia      56.2 
                         13     Drygrain      55.1 
                         14     Drygrain      54.3 
                         15     Drygrain      57.0 
                         16     Drygrain      54.9 
                         17     Ernie_22      59.4 
                         18     Ernie_22      59.4 
                         19     Ernie_22      57.7 
                         20     Ernie_22      58.6