The act was the first to make price support mandatory for corn, cotton, and wheat to help maintain a sufficient supply in low production periods along with marketing quotas to keep supply in line with market demand.
There's massive government interference in agricultural markets because the free market flat-out doesn't work in that industry. Farmers plant in the spring but sell their crops in the fall, so in a free market they have to guess what the fall price of different crops will be and hope they get lucky. If they aren't lucky -- if you grow a bunch of corn but the price of corn bottoms out because everyone in your state grew a ton of corn, too -- you either make almost no profit, or you might even figure that the price is so low that harvesting isn't worth the cost.
Here's a good starting point:
There's massive government interference in agricultural markets because the free market flat-out doesn't work in that industry. Farmers plant in the spring but sell their crops in the fall, so in a free market they have to guess what the fall price of different crops will be and hope they get lucky. If they aren't lucky -- if you grow a bunch of corn but the price of corn bottoms out because everyone in your state grew a ton of corn, too -- you either make almost no profit, or you might even figure that the price is so low that harvesting isn't worth the cost.