[GURPS Basic] Why no farming mechanic?

[Anders]

First mage casts spell
Second mage counters spell
Third mage counters counterspell
Fourth mage counters counter-counterspell
Army turns up and chops them all into bits

[(E)]

Range issues tend to move things in the defenders favour all things being equal

[Verjigorm]

Originally Posted by Celjabba

In most cases, he would be busy countering the decay and pestilence opposing mage ...

More likely, any mage capable of creating food and safe water would be used to keep your besieging troops from getting sick. Sickness in the camps force many a besieger to break off.

Now, of course, I'd rather have my mages use Shape Earth to build a ramp up to the walls and allow me to assault the walls. I mean, moving more dirt in a second than I can move in an hour is a pretty good deal. Or we can pull it out from under the foundations and cause the walls to collapse that way.

[Pursuivant]

Originally Posted by silveroak

However one of the reasons you don't find a lot of rules for agriculture in roleplaying games (especially games which strive for accuracy) is that it is a lot more complicated than you probably imagine. The typical farmer has a skill in farming and an area knowledge skill for the area they farm, and, if a modern farmer, lots of contacts who provide information on things like weather and soil quality.

Very true.

A low-tech farmer is likely to have a point or so in Area Knowledge, Housekeeping, Meteorology (Weather Sense), Naturalist, and Survival (Forest or Grassland), as well as Farming. Possibly add a ranged weapon skill to keep the varmints honest.

A farmer rich enough or advanced enough to also keep livestock on a large scale is likely to have some points in Teamster, Riding and/or Animal Handling.

At TL6, Mechanic skill gets added to the mix.

At TL7, Teamster and Riding skill get demoted to optional skills, and Driving (Agricultural/Construction Equipment, Car, and Truck) and Mechanic (Agricultural Equipment, and/or possibly Cars, Heavy Truck) get added as Secondary skills.

At TL8, add Computer Operations - at least for the more tech-savvy farmers.

Originally Posted by silveroak

If you ever visit the USDA website there is enough information there about soil conditions, fertilizer, weather and crop yields to fill a renassaince library.

That's one of the differences between Farming/TL4 and Farming/TL8.

Originally Posted by silveroak

The reason that medieval agriculture was medieval was that people simply didn't have a lot of the information about how plants grow that we do today

Maybe. Some pre-modern farmers were quite shrewd about keeping their soil in good condition by adding amendments like seaweed (trace minerals) and lime (Ca, Mg), as well as manure. At least for vegetable farming, intensive farming at TL5 (i.e., mid-19th century) could produce yields similar to those obtainable using TL8 (i.e., 21st century) open-field techniques.

But, at lower TL, that might represent higher levels of Farming skill rather than the "baked in" advantage that more modern farmers have due to improved knowledge, seeds, fertilizers, herbicides, pesticides, etc.

Originally Posted by silveroak

crop rotation was all about balancing the impact on the soil of various homogenous crops, including a season letting the soil lay fallow and grow wild while animals grazed for a season (which is a good source of phosphorous).

Modern organic farming practices work on similar principles - one or two cash crops followed by a "green manure" crop which is either used to replenish the soil directly or which is harvested and composted. In between crops, domestic animals might be allowed to forage in the area, both for manuring and for pest control.

Originally Posted by silveroak

In a fantasy universe these rules may not even be the same, or may have other modifiers- growing well in direct light or shade may be complicated by mana levels.

That moves into the realm of GURPS Fantasy, as well as the GM's house rules as to how the world works. The default assumption is that improved mana levels are a wash with respect to plant growth. After all, the same mojo that makes crops grow better might make weeds, pests, and plant disease organisms grow better, too.

Originally Posted by silveroak

For basics, third world countries today produce around a ton to a ton and a half of grain per hectare. Obviously this can range all the way down to zero productivity, the US has roughly 5 times the production (with fertilizer, the aforementioned USDA database, and good irrigation, or roughly 7.5 tons per hectare.

To complicate things, the stats for developing nations don't explain why yields are low. It could be more farming on marginal land, poorer climate, pests, or the effects of poverty, rather than lower TL, which affect yields. So, all you can say is at TL8, a farmer with every factor in his favor is going to get yields of about 7.5 tonnes/hectacre.

[(E)]

That's not even taking soil contour into the equation. Weather is another huge variable, doesn't matter how good you are at farming or how good the soil is, without water nothing grows.

Weather sense/meteorology might get added to the list of farming skills. Pioneering farmers would have a lot of timber work and survival/hunting skills.

[Peter Knutsen]

Originally Posted by Polydamas

If they don't start from a thorough grounding in economic history, they will create rules which build worlds which could not be. I think that farming rules are most likely to be used in settings which are “like our world except for this one thing” rather than ones governed by the laws of narrative, like an Arthurian romance or Star Trek.

That's not what I'm talking about.