In situ grazing is the most common method of feeding crop residues in semi-arid tropical Africa. The prevailing method of storing is to leave the crop residues standing in the field until grazing. Although such field storage would be expected to result in reduced nutritive value (eg loss of leaf), costs of residue harvesting (eg baling) and storing using conventional forage conservation methods would probably be prohibitive to small-scale farmers (Mlay, 1987).
There is a dearth of information on quantitative and qualitative changes in crop residues left standing in fields after grain harvesting. A study was therefore carried out at Mpwapwa, Tanzania to measure the effects of varying the duration of field storage upon the quantity and quality of sorghum stover and lablab bean haulm.