Effects of pre-harvest treatment and mower and header types on seed loss and hard seed content at mowing, recovery, and separation when harvesting a white clover seed crop

Abstract

Abstract A preliminary on-farm survey of white clover (Trifolium repens L.) crop seed losses at pickup for threshing and separation indicated that operator skills and/or machinery were responsible for losses rather than crop management skills. Losses ranged from 12 to 39%, the mean being 200 kg/ha of which 130 kg/ha was hard seed. In subsequent seasons at Lincoln, losses resulting from crop condition at mowing (crops were either cut green or desiccated before cutting morning or afternoon) were measured after cutting by a standard sickle bar (17 fingers/m), a lespedeza bar (25 fingers/m), a double reciprocating knife, or a twin-drum rotary mower. The latter 2 mowers were also assessed in an out-of-condition crop. Losses from mowing ranged from 17 to 59% of the total harvestable seed yield (200–540 kg/ha). Use of a rotating-finger type pickup attachment for swath recovery for threshing reduced mowing losses by 10% to range from 60 to 340 kg/ha. Lowest losses (5%) were recorded on a desiccated crop cut in th...