Land is measured and accounted by the “ar,” or “Farmer’s Grasp” system. Ar accounting is based, not on physical surface area, but on productivity estimates. The basic unit, an “ar,” or “Farmer’s Grasp,” represents approximately 1 cubic meter of fertile, arable soil.

In some terrain, one ar might be thinly spread over many square meters of surface area. In others, one square meter of surface might actually extend several ar deep. Land payments and allotments are made in ar by a Landholder (usually, a Master), to an ar-holder (usually, a Farmer). In return, rents and taxes are paid in produce by the ar-holder to the Landholder, Creditors, and the ar-holder’s Cattle.

Thus, it is generally in everyone’s interest to conserve and increase ar value. For the Landholder, a rise in ar promised an increase in available allotments, and the revenue derived therefrom. For the ar-holder, it meant the possibility of beating the system by getting more produce out of an allotment than it was originally worth.

However, since arability varies with moisture, friability, and other factors, a given plot of land’s value in ar was a matter of continual, intense agronomic negotiation, accounting, and legal dispute between ar-Holder and Landholder. The most vicious disputes arose at two crucial times: (1) following natural disaster, when the ar-Holder tried (often desperately) to shift the burden of responsibility for failed crops or dead Cattle onto someone else; and (2) on an ar-Holder’s death, when final reckoning for all accounts due the Landholder and other Creditors took place.