In the past, the bulk of agricultural production was concentrated in a few limited areas. The produce was largely retained by these communities although some surplus was sold to the cities. Nomads played a crucial role in this regard, shipping foods and other goods between the widely dispersed agricultural areas. Livestock rearing was shared between the sedentary communities and nomads, who also used it to supplement their precarious livelihoods.

Lack of water has always been the major constraint on agriculture and the determining factor on where cultivation occurred. The kingdom has no lakes or rivers. Rainfall is slight and irregular over most of the country. Only in the southwest, in the mountains of Asir, close to the Yemen border and accounting for 3 percent of the land area, was rainfall sufficient to support regular crops. This region plus the southern Tihamah coastal plains sustained subsistence farming. Cropping in the rest of the country was scattered and dependent on irrigation. Along the western coast and in the western highlands, groundwater from wells and springs provided adequate water for selfsupporting farms and, to some extent, for commercial production. Moving east, in the central and northern parts of the interior, Najd and An Nafud, some groundwater allowed limited farming. The Eastern Province supported the most extensive plantation economy. The major oasis centered around Al Qatif, which enjoyed high water tables, natural springs, and relatively good soils.

Historically, the limited arable land and the near absence of grassland forced those raising livestock into a nomadic pattern to take advantage of what forage was available. Only in summer, the year's driest time, did the nomad keep his animals around an oasis or well for water and forage. The beduin developed special skills knowing where rain had fallen and forage was available to feed their animals and where they could find water en route to various forage areas.

Traditionally, beduin were not self-sufficient but needed some food and materials from agricultural settlements. The near constant movement required to feed their animals limited other activities, such as weaving. The settled farmers and traders needed the nomads to tend this camels. Nomads would graze and breed animals belonging to sedentary farmers in return for portions of the farmers' produce. Beduin groups contracted to provide protection to the agricultural and market areas they frequented in return for such provisions as dates, cloth, and equipment. Beduin further supplemented their income by taxing caravans for passage and protection through their territory.

Beduin themselves needed protection. Operating in small independent groups of a few households, they were vulnerable to raids by other nomads and therefore formed larger groups, such as tribes. The tribe was responsible for avenging attacks on any of its members. Tribes established territories that they defended vigorously. Within the tribal area, wells and springs were found and developed. Generally, the developers of a water so3db source, such as a well, retained rights to it unless they abandoned it. This system created problems for nomads because many years might elapse between visits to a well they had dug. If people from another tribe just used the well, the first tribe could frequently establish that the well was in territory where they had primary rights but if another tribe improved the well, primary rights became difficult to establish. By the early twentieth century, control over land, water rights, and intertribal and intratribal relationships were highly developed and complex (see Beduin Economy in Tradition and Change , ch. 2).

Data as of December 1992