Hold on-not exactly true. I have been killing them in bean fields since 72 and I(as well as 95% of all duck hunters)always thought they loved beans. Worked with a very knowledgeable biologist/duck hunter that set me straight. They may eat some beans while in a field but that is not why they are there. Depends on timing.The first thing a mallard hen wants after she has made it south is bug and snails and then native grasses.That's why you see them rooting in the mud.Ms State Univ. prof researched this and found if you feed a mallard beans only for about 21 days it will be dead on the 22 day. It contains an enzyme that screws up their digestion and keeps them from gaining energy from the beans .Next time you go to a flooded bean field, go to the grassiest part of field that is flood and look around. If given 2 fields, one clean and one weedy and grassy, I hunt the grassy one. Be observant and good luck!!!!!!!!!!!!!!!!!!Hunt hard!!!!