There are two main cultivation regimes in the Middle Hills of Nepal: khet (paddy)
and bari (rainfed). The paddy land, with fields of standing water, generally traps
eroded soil and sediment, other than at times of ploughing during intense rain. This
study concerns the more vulnerable bari lands, which are rainfed cultivated bench
terraces where crops are dependent entirely on the monsoon rains for moisture. The
typical cropping cycle is as follows. Maize is sown after sufficient soil moisture has
accumulated from the pre-monsoon rains, usually in May or early June. Prior to
sowing, the soil has generally been tilled twice and organic manure may have been
incorporated. In general, maize is planted in early May and harvested in early to
mid-August. Millet seedlings are then almost immediately planted out, following
hand turning of the soil and the incorporation of organic residues (maize stalks and
weeds). Millet is harvested in November or early December, well after the end of
the monsoon. In some other areas, especially where rainfall is lower or the growing
season shorter, the maize and millet may be intercropped, or a single crop of maize
grown. The cropping cycles give rise to complex patterns of ground cover during
the pre-monsoon and monsoon periods, which significantly influence patterns of runoff
and soil loss