In present day, we can produce about 4.48 metric tons or just shy of 5 US tons per Hectare. (Corn is approx. double the output in the same space) so if we assume 40 square miles of Draj’ green space is taken up by city, roads, estates, etc. that leaves about 50k hectares meaning a production of approx. 246,917 US tons of wheat per annum, the average person needs approx. one ton of food per year and so Draj could hypothetically support a population of 200k without too much concern