I've come to realize the use of farms, so I'd like to share it. I've grown away from the cottage spam, and I hope this will show others the way as well. I'll tell you, this game becomes so much more fun when you have to think more than cottages. I play Random Personalities on Monarch/Emperor difficulty.
I'd like to start out by saying that all of this is for non-Financial traits. As sad as it is, financial leaders can play nearly perfectly by spamming cottages.
There's a simplified rule that governs how many farms you should build at any point in the game. It's not how much food you need to reach size 20. It's how much food you need to hit maximum happiness cap. This is as low as 4 in the early stages of Emperor difficulty, so obviously you're not gonna build any farms until your city can reach at least size 8, in which you just might have a production city if you found a really sweet mining area (2 pieces of production tiles like copper or iron on the same city would be a good example).
That's the real short version of it, but this can become complicated in order to achieve maximum benefit. For sake of simplicity, I'll divide it into 3 categories: Early Game, Middle Game, and Late Game.
Early Game
Early game consists of when your city can only reach size 10 due to happiness, and any growth beyond that is completely pointless. There are 4 factors that govern what to build for your starting cities. I used to think that cottage spamming was the way, but I have found a few exceptions that are not that uncommon. The 4 factors are: Forests, Happiness, Resources, and Limited Workers.
Forests
Everyone knows that chopping forests is the way to go. 3 or 4 extra hammers in the early game is very heavily overshadowed by the power of 30 hammers for every forest(in Normal speed). As such, it's fairly rare to have a production city early.
This is the biggest factor in the early game. A city that emphasizes production must be a city that has only 1 or 2 forests to chop, and even then it may still not be worth building farms.
Happiness
I've already said it, but your city is only worth growing for as many happiness as you have. This is worth mentioning in early game though, just to remind people that +1 happiness=+1 size this early in the game, since almost every city can reach at least size 10. This is also key in envisioning the future, as theaters right around the corner can allow one more size and heriditary rule can make a big difference.
Resources
This is where you just may see the first signs of specialized cities. You still have to weigh in your options, of course. Your first three or four cities will almost always be cottage spammed. There is no choice, hammers are just not that valuable this early when all you can do is spam archers, and more importantly you can chop forests. Another reason is that commerce is halved if you don't, which makes a bigger impact than anything.
Also, most resources are worth working on. Gold on a hill is no-brainer, always build 2 farms on grasslands to work that gold. There are some weak resources that you can take a second thought on. Fur in ice is a good example, you might as well have 2 cottages if you're gonna build 2 farms to work an ice fur. At least the 2 cottages will take 1 less population and grow to make even more commerce later on.
Limited Workers
In the early game, the limited number of workers makes it so you have to be aware of what should be prioritized first. You can of course build more workers, but that also impedes growth and spends hammers so that also needs to be weighed in.
What Does All This Mean?
Simply put, Production is worthless and Commerce is king due to forests. So imagine the best way to achieve the most commerce.
Even after all of this, some cities are born to have farms built. As the most extreme example I can think of that people still usually spam cottages on, picture this: Third City, 2 Floodplains, 2 Forest Grasslands, 1 Gold Hill and 1 Copper mine on Hill, 2 Plains/Hills, 1 Horse on Grassland, and the rest Grasslands in which 5 of them are farmable. Happiness allows you to reach size 10. The first instinct for most would be to cottage this place all the way. That is the easy way, I assure you...all you have to do is build cottages and you can forget about the city as it will be a commerce city. But this is your third city, it's worth giving some extra attention this early in the game.
Try this instead: Farm up the 2 Floodplains and work both of them, and then work the horse (the city will automatically do it for you). You got a size 3 city with 4 hammers already, and an excess of 6 food. Work the gold mine next. You now have a size 4 city producing 11 commerce, 6 hammers and 4 excess food. Work the Copper mine. Size 5, 11 Commerce, 11 hammers and 2 excess food. And from here, you can decide to make this city either cottage spammed to commerce or work the hills at least temporarily as a production city.
Think of the difference here. Because I built the 2 farms on the floodplains, it allowed me to have 2 excess food after working all my special resources which allows me to still grow afterwards. Not only that, it allowed me to grow faster and work more tiles.
As such, any city with gold or any other workable resource that gives 6 commerce or more should build farms immediately, especially if you have no floodplains. 2 farms in grasslands will allow you to work that gold mine at size 3 producing 1 or 2 hammers and 7 or 8 commerce right there depending on the tile, while 2 cottages will only allow for another cottage due to the lack of food surplus.
There's also one occasion in which it may be wise to build farms for production. It's fairly uncommon in the early game, but sometimes more production means more commerce. The key to this is in how many buildings you can build. Say a city that's just starting out can only go up to size 6 due to happiness, and you must build temples and forges to allow for more population. If you founded a city with iron on a hill with grasslands all over and only 1 forest, the best way to start would be to build 2 farms, work the iron, and then spam cottages. Why? Because a size 7 city with all cottages and maybe a library will have a hard time competing with a a size 9 city with a forge, temple, library, granary and one less cottage.
This is also why I said that forests are the most important factor. If there's 3 or 4 forests, the cottage-spammed city can simply chop those buildings and achieve the same grounds while having a head start on commerce.
Still, there is also a matter of limited worker force to consider. I do encourage building 2 farms and a mine if the city has no production otherwise, but it becomes a little shadier when the city already makes 3 or 4 hammers without it. The reason being that if you build 2 farms and a mine, sure you'll have that city getting all the libraries up faster but you probably won't have the time to change the 2 farms into cottages once everything is built. Typically, your workers will be busy building roads or improving new cities which are both higher on the priority list.
For me, 4 hammers is plenty and 3 hammers is also acceptable in the early game. I do the farm-farm-mine only on cities that have 2 hammers or less with only 1 or 2 forests.
Middle Game
Mid-Game consists of city size 10+ and still plenty of time to consider about the 'long-term'. There's a few differences between here and Early Game. New cities have much more to build. Specialization really begins to shape up. Plenty of workers. New civics, new technologies. The 4 factors that govern what to build in this stage of the game are: Happiness, Resources, Specialization, and Strategy.
Happiness
Same as Early Game. It's never worth it to grow over happiness limit.
Resources
Same as early game, except forests just won't cut it if you have 8 buildings to build. Most resources are still worth working on.
Specialization
Ah yes. This is what makes it so interesting. There's 3 types of specialized cities: Commerce City, Production City, and Great People City.
Commerce City in many other threads describes this as a city that sacrifices anything else for just 1 more commerce point. This is not my definition. Think about it, no 'Pure Commerce' city will ever be effective. You have so many buildings to build that you're going to need at least some hammers. Even if you have all your stuff built, you're still going to have a lot of units to build to support your newer cities.
So, commerce cities are all those cities that have cottages spammed but still have at least 4 hammers to make themselves useful. A lot of threads define this as the 'Commerce/Production hybrid' but to me, there's no such thing as a Commerce specialized city.
This is also the type of city that most or all of your Early Game cities are categorized in.
Production City is a city that focuses on hammers more than anything else. You won't need many of these. A relatively peaceful civ can live by with one. You may even have none if you don't find a particularly good spot for it.
The ideal spot for production cities are cities with a lot of production resources like iron and cows, and also a lot of food with hills. There won't be many places that can only be a production city, so you'll basically have to decide which city to make a production city if you're really blessed with a lot of food everywhere. This is common in Great Plains. Basically, it's the location that you think will not have too much commerce anyways.
That said, I'll give an extreme example of what's going to be a production city no matter what. 6th City, happiness after all buildings allows city to go to size 13. 1 pig on a hill, 1 wheat on a grassland river, 3 farmable grasslands, 5 hills, 1 unfarmable plains, and the rest all desert. A lot of food and not enough land to make good use of it with commerce. Just build farms on all the grasslands and plains, and then mine up the hills. You'll have 4 food from pigs, 6 from the wheat, 9 food from grasslands, and 2 surplus initally = 21 total, which means if you work the plains then you'll have a size 11 city. You can work 5 hills for a total base production of 21. That's a strong production city.
If you notice, production cities are small. There will very rarely be a big production city, because all the excess food will be there only to work the no-food hill or the 1-food hill/plains. Most of my cities that can't grow to a large size anyways will turn out to be production cities. Cities that have 7 or 8 deserts/tundra/peaks makes good candidates. They won't make a good commerce city anyways.
That said, there are limits to this. It is possible to have TOO MANY production cities. There's only so much military that you can use, and if you got too much then these cities will sit there doing nothing. You have to pay 1 gold per military unit, although you can get some for free. Check the Financial advisor for how many free units you can build(Press F2 for the financial advisor).
Great People City is a city that simply produces a lot of Great People. They do with a lot of specialists. Specialists cost 2 food, basically meaning you sacrifice a tile for a specialist. Each specialist gives 3 points to your Great People Points.
You're looking for places with an extremely large abundance of food. Floodplains, Pigs, Wheat, Grasslands, Etc. with little hills or unworkable tiles. What you build here is simple: Farms and nothing but farms. You want to get as much population as possible. Be sure to start out with a mine or maybe even two.
I strongly encourage starting these cities as production cities. I always build National Epic and Globe Theater here, so there's a considerable amount of hammers needed. Just be sure not to build those first, because they'll produce one or two unwanted Great Artists...unless you're going for a cultural victory.
Strategy
Strategy is what you plan to aim for to achieve victory. Warmongers will make use of more Production Cities. Tech runners will not need as much. Wonder builders will use more also.
What Does All This Mean?
Production becomes much, much more important now that all the forests are gone and a constant supply of hammers are needed.
Specialization is also very important as the empire grows. Ideally, I want 1 Great People City, 3 Major Production Cities(20+ hammers), and the rest smaller Production Cities and Commerce Cities.
Strategy should be taken into account for the long-term. As you may have guessed, I'm a warmonger when possible and feasible. I am still good at other victories when warmonger is not an option, and I found that the differences for me is simply in the number of Major Production Cities. I'll always make cities that can't grow big into Production Cities, cities that can grow big into Commerce Cities, and 1 Great People City. If there's no good site for a Major Production City, then I might just not have one if I have enough small Production Cities.
I'd like to start out by saying that all of this is for non-Financial traits. As sad as it is, financial leaders can play nearly perfectly by spamming cottages.
There's a simplified rule that governs how many farms you should build at any point in the game. It's not how much food you need to reach size 20. It's how much food you need to hit maximum happiness cap. This is as low as 4 in the early stages of Emperor difficulty, so obviously you're not gonna build any farms until your city can reach at least size 8, in which you just might have a production city if you found a really sweet mining area (2 pieces of production tiles like copper or iron on the same city would be a good example).
That's the real short version of it, but this can become complicated in order to achieve maximum benefit. For sake of simplicity, I'll divide it into 3 categories: Early Game, Middle Game, and Late Game.
Early Game
Early game consists of when your city can only reach size 10 due to happiness, and any growth beyond that is completely pointless. There are 4 factors that govern what to build for your starting cities. I used to think that cottage spamming was the way, but I have found a few exceptions that are not that uncommon. The 4 factors are: Forests, Happiness, Resources, and Limited Workers.
Forests
Everyone knows that chopping forests is the way to go. 3 or 4 extra hammers in the early game is very heavily overshadowed by the power of 30 hammers for every forest(in Normal speed). As such, it's fairly rare to have a production city early.
This is the biggest factor in the early game. A city that emphasizes production must be a city that has only 1 or 2 forests to chop, and even then it may still not be worth building farms.
Happiness
I've already said it, but your city is only worth growing for as many happiness as you have. This is worth mentioning in early game though, just to remind people that +1 happiness=+1 size this early in the game, since almost every city can reach at least size 10. This is also key in envisioning the future, as theaters right around the corner can allow one more size and heriditary rule can make a big difference.
Resources
This is where you just may see the first signs of specialized cities. You still have to weigh in your options, of course. Your first three or four cities will almost always be cottage spammed. There is no choice, hammers are just not that valuable this early when all you can do is spam archers, and more importantly you can chop forests. Another reason is that commerce is halved if you don't, which makes a bigger impact than anything.
Also, most resources are worth working on. Gold on a hill is no-brainer, always build 2 farms on grasslands to work that gold. There are some weak resources that you can take a second thought on. Fur in ice is a good example, you might as well have 2 cottages if you're gonna build 2 farms to work an ice fur. At least the 2 cottages will take 1 less population and grow to make even more commerce later on.
Limited Workers
In the early game, the limited number of workers makes it so you have to be aware of what should be prioritized first. You can of course build more workers, but that also impedes growth and spends hammers so that also needs to be weighed in.
What Does All This Mean?
Simply put, Production is worthless and Commerce is king due to forests. So imagine the best way to achieve the most commerce.
Even after all of this, some cities are born to have farms built. As the most extreme example I can think of that people still usually spam cottages on, picture this: Third City, 2 Floodplains, 2 Forest Grasslands, 1 Gold Hill and 1 Copper mine on Hill, 2 Plains/Hills, 1 Horse on Grassland, and the rest Grasslands in which 5 of them are farmable. Happiness allows you to reach size 10. The first instinct for most would be to cottage this place all the way. That is the easy way, I assure you...all you have to do is build cottages and you can forget about the city as it will be a commerce city. But this is your third city, it's worth giving some extra attention this early in the game.
Try this instead: Farm up the 2 Floodplains and work both of them, and then work the horse (the city will automatically do it for you). You got a size 3 city with 4 hammers already, and an excess of 6 food. Work the gold mine next. You now have a size 4 city producing 11 commerce, 6 hammers and 4 excess food. Work the Copper mine. Size 5, 11 Commerce, 11 hammers and 2 excess food. And from here, you can decide to make this city either cottage spammed to commerce or work the hills at least temporarily as a production city.
Think of the difference here. Because I built the 2 farms on the floodplains, it allowed me to have 2 excess food after working all my special resources which allows me to still grow afterwards. Not only that, it allowed me to grow faster and work more tiles.
As such, any city with gold or any other workable resource that gives 6 commerce or more should build farms immediately, especially if you have no floodplains. 2 farms in grasslands will allow you to work that gold mine at size 3 producing 1 or 2 hammers and 7 or 8 commerce right there depending on the tile, while 2 cottages will only allow for another cottage due to the lack of food surplus.
There's also one occasion in which it may be wise to build farms for production. It's fairly uncommon in the early game, but sometimes more production means more commerce. The key to this is in how many buildings you can build. Say a city that's just starting out can only go up to size 6 due to happiness, and you must build temples and forges to allow for more population. If you founded a city with iron on a hill with grasslands all over and only 1 forest, the best way to start would be to build 2 farms, work the iron, and then spam cottages. Why? Because a size 7 city with all cottages and maybe a library will have a hard time competing with a a size 9 city with a forge, temple, library, granary and one less cottage.
This is also why I said that forests are the most important factor. If there's 3 or 4 forests, the cottage-spammed city can simply chop those buildings and achieve the same grounds while having a head start on commerce.
Still, there is also a matter of limited worker force to consider. I do encourage building 2 farms and a mine if the city has no production otherwise, but it becomes a little shadier when the city already makes 3 or 4 hammers without it. The reason being that if you build 2 farms and a mine, sure you'll have that city getting all the libraries up faster but you probably won't have the time to change the 2 farms into cottages once everything is built. Typically, your workers will be busy building roads or improving new cities which are both higher on the priority list.
For me, 4 hammers is plenty and 3 hammers is also acceptable in the early game. I do the farm-farm-mine only on cities that have 2 hammers or less with only 1 or 2 forests.
Middle Game
Mid-Game consists of city size 10+ and still plenty of time to consider about the 'long-term'. There's a few differences between here and Early Game. New cities have much more to build. Specialization really begins to shape up. Plenty of workers. New civics, new technologies. The 4 factors that govern what to build in this stage of the game are: Happiness, Resources, Specialization, and Strategy.
Happiness
Same as Early Game. It's never worth it to grow over happiness limit.
Resources
Same as early game, except forests just won't cut it if you have 8 buildings to build. Most resources are still worth working on.
Specialization
Ah yes. This is what makes it so interesting. There's 3 types of specialized cities: Commerce City, Production City, and Great People City.
Commerce City in many other threads describes this as a city that sacrifices anything else for just 1 more commerce point. This is not my definition. Think about it, no 'Pure Commerce' city will ever be effective. You have so many buildings to build that you're going to need at least some hammers. Even if you have all your stuff built, you're still going to have a lot of units to build to support your newer cities.
So, commerce cities are all those cities that have cottages spammed but still have at least 4 hammers to make themselves useful. A lot of threads define this as the 'Commerce/Production hybrid' but to me, there's no such thing as a Commerce specialized city.
This is also the type of city that most or all of your Early Game cities are categorized in.
Production City is a city that focuses on hammers more than anything else. You won't need many of these. A relatively peaceful civ can live by with one. You may even have none if you don't find a particularly good spot for it.
The ideal spot for production cities are cities with a lot of production resources like iron and cows, and also a lot of food with hills. There won't be many places that can only be a production city, so you'll basically have to decide which city to make a production city if you're really blessed with a lot of food everywhere. This is common in Great Plains. Basically, it's the location that you think will not have too much commerce anyways.
That said, I'll give an extreme example of what's going to be a production city no matter what. 6th City, happiness after all buildings allows city to go to size 13. 1 pig on a hill, 1 wheat on a grassland river, 3 farmable grasslands, 5 hills, 1 unfarmable plains, and the rest all desert. A lot of food and not enough land to make good use of it with commerce. Just build farms on all the grasslands and plains, and then mine up the hills. You'll have 4 food from pigs, 6 from the wheat, 9 food from grasslands, and 2 surplus initally = 21 total, which means if you work the plains then you'll have a size 11 city. You can work 5 hills for a total base production of 21. That's a strong production city.
If you notice, production cities are small. There will very rarely be a big production city, because all the excess food will be there only to work the no-food hill or the 1-food hill/plains. Most of my cities that can't grow to a large size anyways will turn out to be production cities. Cities that have 7 or 8 deserts/tundra/peaks makes good candidates. They won't make a good commerce city anyways.
That said, there are limits to this. It is possible to have TOO MANY production cities. There's only so much military that you can use, and if you got too much then these cities will sit there doing nothing. You have to pay 1 gold per military unit, although you can get some for free. Check the Financial advisor for how many free units you can build(Press F2 for the financial advisor).
Great People City is a city that simply produces a lot of Great People. They do with a lot of specialists. Specialists cost 2 food, basically meaning you sacrifice a tile for a specialist. Each specialist gives 3 points to your Great People Points.
You're looking for places with an extremely large abundance of food. Floodplains, Pigs, Wheat, Grasslands, Etc. with little hills or unworkable tiles. What you build here is simple: Farms and nothing but farms. You want to get as much population as possible. Be sure to start out with a mine or maybe even two.
I strongly encourage starting these cities as production cities. I always build National Epic and Globe Theater here, so there's a considerable amount of hammers needed. Just be sure not to build those first, because they'll produce one or two unwanted Great Artists...unless you're going for a cultural victory.
Strategy
Strategy is what you plan to aim for to achieve victory. Warmongers will make use of more Production Cities. Tech runners will not need as much. Wonder builders will use more also.
What Does All This Mean?
Production becomes much, much more important now that all the forests are gone and a constant supply of hammers are needed.
Specialization is also very important as the empire grows. Ideally, I want 1 Great People City, 3 Major Production Cities(20+ hammers), and the rest smaller Production Cities and Commerce Cities.
Strategy should be taken into account for the long-term. As you may have guessed, I'm a warmonger when possible and feasible. I am still good at other victories when warmonger is not an option, and I found that the differences for me is simply in the number of Major Production Cities. I'll always make cities that can't grow big into Production Cities, cities that can grow big into Commerce Cities, and 1 Great People City. If there's no good site for a Major Production City, then I might just not have one if I have enough small Production Cities.