The great Islamic cities of the Near East, North Africa and Spain, Artz explains, were supported by an elaborate agricultural system that included extensive irrigation and an expert knowledge of the most advanced agricultural methods in the world.
The Muslims reared the finest horses and sheep and cultivated the best orchards and vegetable gardens. They knew how to fight insect pests, how to use fertilizers, and they were experts at grafting trees and crossing plants to produce new varieties.
Glick defines the Muslim agricultural revolution in the introduction of new crops, which, combined with extension and intensification of irrigation, created a complex and varied agricultural system, whereby a greater variety of soil types were put to efficient use;
where fields that had been yielding one crop yearly at most prior to the Muslims were now capable of yielding three or more crops, in rotation; and where agricultural production responded to the demands of an increasingly sophisticated and cosmopolitan urban population by providing the towns with a variety of products unknown in Northern Europe.
Whilst for Scott, the agricultural system of the Spanish Muslims, in particular, was `the most complex, the most scientific, the most perfect, ever devised by the ingenuity of man.’
Fertilizers, in their variety, were used according to a well-advanced methodology; whilst a maximum amount of moisture in the soil was preserved.
Soil rehabilitation was constantly cared for, and preserving the deep beds of cropped land from erosion was, according to Bolens, again, `the golden rule of ecology,’ and was `subject to laws of scrupulous careful ecology.’
The rise of productivity of agricultural land and sometimes of agricultural labour owe to the introduction of higher yielding new crops and better varieties of old crops.
Irrigation, from Andalusia(Spain) to the far East, from the Sudan to Afghanistan, remained central, `the basis of all agriculture and the source of all life.’
The Muslims repaired them and constructed new ones; besides devising new techniques to catch, channel, store and lift the water, and making ingenious combinations of available devices.