A Companion to Ancient Agriculture, First Edition. Edited by David Hollander and Timothy Howe. © 2021 John Wiley & Sons, Inc. Published 2021 by John Wiley & Sons, Inc. The zone from the Zagros Mountains and the Iranian plateau to the Amu‐darya and Syr‐ darya river valleys of southern Central Asia has historically supported a close symbiosis between settled agriculture and a mobile pastoral economy. In the second half of the first millennium BCE, this region formed the northeastern marches of the Achaemenid Persian empire and the Seleucid empire. These empires, which will be the primary focus of this chap- ter, struck a balance between centralized management of agriculture and careful maintenance of effective local systems of controlling the natural environment and maximizing resource extraction. Across such a vast and geographically diverse region, two areas have been the focus of par- ticular scholarly attention: the Zagros mountains of present‐day western Iran, and the rivers and endorheic basins of Afghanistan, Turkmenistan, and Uzbekistan. Both are regions of great agricultural potential, but are vulnerable to changes in climate and poor management; conversely, individual and state intervention, especially in the management of water resources, can increase productivity. Farming and Water Management in Central Asia Southern Central Asia, the northeastern fringe of the Achaemenid and Hellenistic empires, is characterized by large expanses of arid land, unsuitable for arable farming. Rivers originating in the region’s mountain ranges, most notably the Hindu Kush, make settled agriculture pos- sible. Several micro‐regions – the alluvial fans of the Balkh and Murghab rivers, and smaller‐ scale irrigation systems based upon the course of the upper‐mid Oxus/Amu‐darya – have been subject to archaeological investigation, and form the basis of my discussion here. Agriculture has in turn supported the development of urbanism in river oases: the cities of Merv in the Murghab delta and Bactra in the Balkh oasis. The Persian province and later Greek kingdom of Bactria extended from the Pamir Mountains in the east, along the basin of Iran and Central Asia in the Achaemenid and Hellenistic Periods Rachel Mairs CHAPTER TWENTY-SEVEN