Courtesy of https://acoup.blog/2019/07/12/collections-the-lonely-city-part-i-the-ideal-city/ I bring you a summary of the agricultural boundaries around your average city. The biggest driver here is transportation costs-so roads and especially rivers and ocean ports distort the map. While it might not make sense to travel 100 miles by donkey-cart to bring your apples to market, putting them on a ship and taking them across 100 miles of sea makes perfect sense.
-Closest in of all, sometimes inside the walls, sometimes right outside them, you’ve gotta have your horticulture and Dairy zones. Vegetable gardens, pen-fed animals, things that spoil quickly and need a lot of work to get the best results from. Milk goes off quickly, unless you start making cheese right away, so dairy maids need to collect from relatively dense farms that are sometimes inside city walls. This land is so close to market that there’s no reason to not wring every scrap out of it. That means you get irrigation, terracing, and lots and lots of day-labor when you need weeding, harvesting or other activities. The manure of the city and the animals brought into it can also be used as fertilizer. Classical high-inputs, high-outputs style of farming, that’s what you’re looking at.
-Forestry is the next ring out. “Forestry?” I hear you cry. “What kind of fresh nonsense is this?” Well don’t think of this as your typical stand of pines for construction material-this is forestry for firewood, and that means it’s highly managed and often squeezed into spaces between other land uses. Obviously, a city of dwarfs with a coal mine, or a city with magical steam-heating aren’t going to need as much wood, so this can vary in size depending on the climate and the supply needed. Trees in this ring are generally cut intentionally to produce long, thin branches, and cut on a cycle so that they are sustainably harvested. Wood is cheap, but it’s also heavy so transportation costs are high, and it’s thus ideal to keep them low with a constant local supply.
-Grain agriculture dominates the next zone out-well, grains, pulses, wine grapes, olives, whatever your dominant crops are. Obviously, at this layer, we have varrying densities of production depending on the exact productivity of the land, which can be mixed with the 4th zone if the productivity of the land is low enough. The dominant organizational structure out here is the village, each of which will have a cluster of houses and fields worked either communally or by individual families radiating outwards in some fashion. This is a HUGE area-a city of 500,000 people would need an area of land equal to the state of Massachusetts.
-The final zone is that of ranchers, and pastoralist herders. Meat on the hoof travels *very* well, so it can be farmed at huge distances from the cities and then driven by whatever your equivalent of cowboys are to market. Or maybe your dominant animal is geese or pigs, but anything with legs can just walk itself to slaughterhouses. Grazing lands need to be big because you need both lowland and upland grazing to provide abundant pasture in all seasons. This is a FREQUENT cause for strife, because what looks like an empty field to you, a farmer, is a rancher’s wintering grounds and he will slit your throat if you bring a plow near it. However, agriculture tends to push less-dense pastoralists out in the long term-Unless You Are the Mongols.