How big should farms be?

[Gandwarf]

http://www.hyw.com/books/history/Agricult.htm

Two interesting parts of this text:

1. In England, the ideal farm size for a family was a "yardland" (24-30 acres) in size. Only about a quarter of the English farm families had this much land (or a bit more) before the Bubonic Plague , most had ten or fewer. Those farmers possessing a yardland were able to work their land efficiently enough to feed themselves and produce a surplus for sale.

2. An acre of barley could, in an average year, produce about 500 liters of grain (after making allowances for taxes and seed for the next crop). This was enough to feed one adult for a year at a very basic level. A farmer with a wife and two children could get along with five acres. Everyone would have to work, especially for other sources of food like the vegetable garden and rummaging in the woods for mushrooms, nuts, and berries. But a five acre holding left little margin for bad weather. Several bad years in succession could lead to widespread famine.

[Midgardsormr]

For a contrast to the traditional European agricultural style, there is also swidden agriculture, otherwise known as "slash and burn." Data from here: http://lucy.ukc.ac.uk/sonja/rf/ukpr/Report62.htm

indicates that the Semai of Malaysia require approximately one acre of land to feed two people. The fields are cleared and burned over a three-month period, then planted continually for 1 - 2 years, then left fallow for at least 12 years to allow the forest to grow back.

This kind of agriculture is practiced by a number of aboriginal people in South America, as well. Among the Waorani, each family is responsible for feeding itself, and very little food is left over for sale or sharing. Among most of these societies, no one owns land—whoever prepares a swidden owns it only as long as they are cultivating it. The next time around, a different family might be farming on that land.

[Sigurd]

Don't forget that farmers are not the only ones that eat from the harvest. To feed the gentry and the higher ups, you need a lot of farms.

Oh yeah, also Bill Stickers ate my baby!