Imagine this scene: to one side, scorched earth, with tiny castor bean plants dying of thirst. Five yards from that, a green wall two meters high, a complex mixture of castor beans, pigeon peas, jack beans, sesame, cowpeas, opuntia (nopales- an edible cactus) fodder trees, and young fruit trees. Below this mass, the soil is so humid that one might think that it had just rained.