That's basically it.
Here is what I do:
ALWAYS irrigate desert (need the food, as it has 0 food)
ALWAYS forest tundra, when you can't, mine it
For hills and mountains, always mine (obviously)
No, for everything else, it gets tricky.
ALWAYS cut down forests, except on tundra
Plains
Grassland
Bonus Grassland
The above are "flat land." They should follow teh following code:
Mine all tiles, except irrigate one tile for every two hills in the city radius, and irrigate one tile for each mountain. When you have the choice of what to irrigate, irrigate Bonus Grassland, as it already produces a fair amount of shields.
SAMPLE CITY:
H M H
P H H BG G
P P C G G
P P P P P
D D D
Key: H=Hills M=Mountain P=Plaines BG=Bonus Grassland G=Grassland C=The City D=Desert.
Now, assuming we can irrigate any D, P, G, or BG, we would do the following:
M M M
M M M I M
M M C I I
M M M M M
I I I
Key: M=Mine I=Irrigation C=The City
I have irrigated the BG, and two G, because we have four hills (two irrigations), and one mountain (one irrigation). I then irrigated three Ds, because they are deadly without food. Some people may choose to mine desert, but I don't. So, that's my strategy.
EDIT: I had spaced the city properly, but it won't let my post it correctly
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