The performance of three white clover cultivars (Huia, Tahora and Prop) was monitored in summerdry hill country at the Whatawhata Research Centre for 9 years. The cultivars were oversown into three steep north-aspect paddocks in autumn 1990. White clover abundance was measured every spring using line transects, and stolon fragments were sampled to determine the contribution of the cultivars to overall populations by allozyme electrophoresis on three occasions (1991, 1993, and 1994). White clover abundance declined from ~50% in the first year to ~4% in 1999. There were no significant differences in abundance between the three cultivar treatments after year 2. There were significant differences in the contribution of the cultivars to white clover populations after 5 years as follows: Huia 27%, Tahora 33% and Prop 56%. The implications of these results for introducing new white clover genotypes into summer-dry hill country are discussed. Keywords: 'Grasslands Huia', 'Grasslands Tahora', hill country, long-term, 'Prop', summerdry, white clover
