Verified Answer :

Many families had no money and that means they could not but
anything.  This not only affected farmers
but manufacturers as well because no one was buying.   This
caused factories and other business were to close.  When farmers tried to produce more it did
more harm than good due to low prices, more crops only lowered the value even
more.

Neuron

A long term effect of the lost farms was that these people would move to cities because the alternaive was to starve to death. The lands which weren't being converted into farms in future years would slowly but surely turn into wilderness. It all depends on which farms and about what locations we're talking about.