Jack Bean vs. Sword Bean: Identification and Edibility

Q: A friend got bean seeds from his dad called "Fala beans"—maybe fava beans? But these are 12 inches long! He says they're good eating.

Your friend has either jack bean (Canavalia ensiformis) or sword bean (Canavalia gladiata). They look similar, but the "eye" (hilum) of a sword bean exceeds half the seed length. Both are edible when young but cause severe indigestion at maturity. Their best use? Telling stories to children!