A jerib is the most common unit for measuring land in Afghanistan. One jerib is 2000m², or 1/5th of a hectare. Which sounds simple enough. Of course, it isn’t.
Ask a farmer in Ghor, as one example, how much land they farm, and the answer will probably be along the lines of eight man. Ask a farmer in Behsud the same question and you may be told four seer. Both these farmers would be farming, in theory, one jerib.
A seer is usually a unit of weight. One seer equals 4kg. Or 7kg. Or perhaps somewhere in between 4 and 7 kg. It depends which part of the country you are in. A man is also a unit of weight. This also varies on which part of the country you are in. 7kg in Kabul, for example, 4kg in Herat and 14kg in Balkh.
I thought I would try to ham things up a bit and make this all seem as complicated as possible in a desperate bid to garner sympathy but heck, I really don’t need to bother.
Both seer and man may also be used as units of area. When a farmer in Behsud says he is farming four seer of land, what he means is the area of land he farms is the equivalent of four seer’s worth of seed sown. This should equal one jerib. But, maybe it doesn’t. The area of land one bag of seed may cover depends on the land being farmed. The land may be your standard four seer per jerib kind of land, or it may be five seer per jerib land.
If instead of planting wheat seed the farmer is planting potatoes, the unit of weight to a given area will, I think, be very different again.
In Ghor, we’d be talking about man per jerib. In theory, we have eight man per jerib. Trying to pin this thing down there one time and cross checking with various people, I got so many different formulas of x number of man per jerib I gave up all hope of ever getting reliable survey data on harvests and yields and decided I may as well just make the numbers up back in the comfort of Kabul. With no reliable conversion between units my carefully designed study, beautiful database and pain-staking analysis may have been as good as nought (or would have been if I hadn’t added an extra six page questionnaire to the original one and combined it with analysis of satellite images just to figure it out).
Maybe not quite, but remember this next time you read the results of a survey of wheat or opium yields carried out across several different provinces. Conversions aren’t easy. Lies, damned lies, statistics and statistics in Afghanistan.
By the way, I’m writing this from memory so anyone after the facts would do well to double-check.