Toronto and many large cities in North American have the unfortunate quality of being built where the best farm land in the area was... because that was where the food supply would support the population. The stat that my grade 11 geography teach quoted was 90% of the best farmland in all of Canada can be seen from the top of the CN tower. What do we do with it? Build condo's :)

I was reading a BBC write up about a UN study group trying to figure out the best way to effectively feed nations that have issues with drought and starvation... apparently the best return per dollar invested was rooftop gardens due to the ability to control all the variables. Well that and the food can all be grown within feet of a large population centre. Just thought I should say hello and stuff =P