Does farmlands deteriorate?

[Omi-san]

If you put a Power plant near farmlands, will they change from green to yellow and red?

I never really verified this, but I remember a game where it seemed that urbanism affected my farmlands. My corn field where all yellow while I'm sure I built them on green.

[Mercator]

They only change based on soil conditions (which DOES mean the number of people who tread over it), and wetness.  I've never put a powerplant near one, but I have put other bigtime industry near my farms and I never saw any problems outside the norm.

If the land around farms goes to red, its most likely you farmed that soil dry.  Try changing the farm to corn or some other crop for a few seasons.  Then switch it back and your soil should be ok again.  You know, crop rotation!  It revolutionized farming!

[Protista]

I have found that the farm production gradually declines after a lengthy period of years (30-60) in a given area, but you can offset this by constantly expanding agriculture by building new farms in outlying areas. It does appear encroachment by housing or other buildings lessens production of the particular farm in question, but it does not seem significant. I find agriculture to be quite a revenue booster, and adds much to the scenery asthetically.  It also does not seem to cause much problem with the environmental groups.

[Genu]

i realized that farmland decrease or increase depending on the year... like one year it's yellow, the other its green, and it keeps changing... possible?

[Goose]

Or it could just mean the amount of rain that area is getting is changing.

[bradkay]

A lot of people here have talked about rotating crops being the key to food production, but I have never found the need to do so. Yes, you do have years where production drops, but it does appear to come back - like Goose (oops, i thought that you were Eddie!), I believe that it's more a result of rainfall patterns rather than soil depletion. Unlike real life, crops grow too slowly on Tropico to make it easy to rotate them (a corn crop does not grow to fruition in a single year), and so I've found it easier to add farms rather than rotate them.

Of course, I'm not an expert at this game. I've done okay, but so far only on moderate settings. Maybe Dave or Phil can tell us if they actually programmed crop rotation into the mix....

[Sleeping_Dragon]

Have to say I'm with bradkay on this one, it usually isn't worth the trouble.  I don't seem to run into many cases where the soil goes bad and stays that way long. It seems to me the soil conditions are more dependent on when the rain clouds come then anything else.  The exception being buildings crowding in the field and those lazy peasants stomping down the crops with thier short cuts.  It thoise cases it's just time to pack up the cow and move.

[Scrogdog]

I'm pretty sure proximity to other farms (as well as urban areas) matters as well. I've had tobacco farms last 70 years without a problem as long as they are spread out. Most times the 4 starting farms you get are way too close to each other.

[Coconut Kid]

Maus' summary of Computer Games article published approx. 7/01
...
4) Crops. Q: One of the most frustrating things in a game is to develop a dependency on a single cash crop, only to notice later that the land devoted to the farms has turned orange, indicating that it is unsuitable for that crop.  Is crop rotation necessary, or is the change purely climatic?  Can you anticipate changes by using the info overlays for soil and rain?  
A: Rotating crops has no impact.  It's purely climate related, based on rainfall.  The initial values for crop suitability are are based on the game running an internal weather model for 80 years at game start, and averaging the results.  Of course, it's a long-term average, and there are short-term fluctuations. Steinmeyer: "I usually just accept that there will be good and bad harvests, based on the rainfall... I don't typically adjust my crop patterns too much after I've built a farm."
...

However, a couple of posts in this thread seem to indicate that the radiated pollution effects of buildings and the impact of units moving (perhaps unit radiated pollution) have a cumulative, negative effect on soil quality. I know of no careful study and report of that issue. None-the-less, crop rotation is not particularly useful just for itself. It won't hurt for other planned changes of land use. The farm boundaries are five tiles from the building.

Remember, T3 greatly elaborated the farming model.

[Coconut Kid]

Since my previous post, I have found some information which better connects the dots on this issue.

Soil Conditions:

• Soil Quality = five levels
  • Set by map generator
  • Indicated by "paint" level of grass
  • Deterioration is caused by exposure to pollution
    • Farms radiate pollution 2\10 to show exhaustion
    • Equal for all crops
  • No recovery from pollution although it may be masked
• Soil Wetness = five levels (probably)
  • 80 year average computed by map generator
  • Annual level set by passage of clouds (rainfall)

.
Quality and Average Wetness are the most important (along with altitude) indicators for initial placement of farms and ranches. The deterioration of Quality is usually slow unless buildings with high pollution are intermingled with the farms. The big annual variation in output is caused by the changes in rainfall patterns. This is a simulation of "regional" droughts, etc. The crops with greater sensitivity to soil wetness usually require a greater number of farms to produce a steady quantity of goods. Build them on a NW to SE axis to cross the rainfall pattern.