The Tyee has an interesting article about the Cariboo Potato. The Cariboo is a potato native to the area it is named for and has worked well there for generations as a small scale potato. It is not a great potato for mechanized harvesting and therefore the Canadian government banned it. Yes, the government decided what could be grown and what could not.
There is a sub-text in the article that this old variety of potato is a slap in the face of capitalism, but really it is a slap in the face for top down government interference. In a free enterprise system no one would be stopping anyone from growing something.
Starting in the 1920s and escaltign wildly during World War 2 and then going on for decades the governments in Canada intervened in a huge number of aspects of of our day to day lives. We had prohibition of alcohol, which was lifted, and of marijuana. What you grew had to sold through marketing boards, many of which still survive today. Transportation of fruits and vegetables around the province was restricted. In general the government was looking for more and more places to regulate our lives.
This interference was first attacked by the hippies in the late 1960s and then by the free market libertarians in the 1980s, but we still have vestiges of the insanity around us in our food system.
Many organic growers can not sell what they want to produce because they can not afford to buy the 'right' to produce the product regulated by a marketing board - eggs, cheese and milk fall under this.
Growing interesting high quality niche varieties is not possible on the praries because everything has to be sold through the Canada Wheat Board. If you go to Alberta and buy a bushel of wheat from a grower, you are breaking the law.
There are more examples out there I could name, but suffice it to say that I am glad to see the Cariboo Potato is alive and well and fighting the oppressive government system.