john: lisa geller of the john hopkins center for gun violence solutions. thank you very much. ank you for having me. ♪ john: to many people, florida means oranges. this year florida projects the , worst citrus harvest since the great depression. william brangham examines what's driving this decline, which threatens a way of life for many floridians. william: in central florida, orange groves stretch for as far as the eye can see. what is not so visible is the disease that's slowly killing one of this state's biggest industries. so, if i didn't know better, i would look at this and think, like, this looks like you've got a lot of fruit. the tree looks pretty decent to me. [laughter] >> it looks like a lot of fruit because you don't know how much fruit should be on the tree. these trees are, are suffering. they are not generating an economic crop. william: frank hunt is a third generation citrus grow. his grandfather, deeley, started the hunt brothers' family business in lake wales, florida a century ago. all that fruit that's dropped, that's waste. frank: yea that's waste. you c