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Context. Tagasaste (Cytisus proliferus) has potential to supplement pasture production in steephill country and increase pasture resilience. Aims. To (1) quantify production of edible dry matter (EDM) of pruned 2-year-old tagasaste shrubs and branches from unpruned 10-year-old tagasaste trees, and (2) determine the effect of proximity of the 10-year-old tagasaste trees on selected pasture species established as spaced transplants. Methods. A site was established on the eastern coast of the North Island of New Zealand on steep-hill country (>20° slope). Tagasaste and pasture species production was measured over 3 years. Results. Tagasaste −1 shrubs produced an average of 2.7 kg EDM shrub −1 year and a tree branch produced 129 g EDM year −1 . The metabolisable energy content of tagasaste branches averaged 10.0 MJ kg EDM −1 , the crude protein content ranged from 18% to 27% and neutral detergent fibre content averaged 39%. Branch diameter and length were poor predictors of EDM branch −1 . There was no effect of increasing proximity to tagasaste on DM production of the resident pasture. Effects of increasing proximity to tagasaste on the growth and survival of selected pasture species are reported in a companion paper. Conclusions. Edible-DM production was much greater from shrubs than tree branches and it was not possible to predict branch EDM from branch diameter or length. Implications. A tagasaste silvopasture is likely to be more productive if tagasaste is managed for grazing in situ than if using mature trees for harvesting of branches for browse.

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Two experiments were conducted to examine the effects of biological (composition and site history) and topographic (slope and aspect) factors affecting sheep dung disappearance rates in hill country pastures. We used three of the farmlets that have been receiving 0 (NF), 125 (LF) or 375 (HF) kg of single superphosphate (SSP)/ha since 1980) from the long-term phosphorus fertiliser trial at Ballantrae. Experiment one examined the effect of farmlet, slope (low and medium slope class), and aspect (E, SW, NW), whereas Experiment two examined the effect of farmlet, both as a source of dung (from LF or HF farmlets) and as a site in the landscape (on LF or HF farmlets). In both experiments, disappearance of dung followed a quadratic curve, and no improvements were made using higher-order polynomials. Despite a lower fibre concentration, dung from sheep grazing the HF farmlet did not disappear at a faster rate than dung from the other farmlets, but soil activity in situ (placement) was pivotal to the rate of dung disappearance. A faster rate of dung disappearance on the HF farmlet is consistent with a greater capacity for turnover of plant biomass and animal excreta in this high fertility environment. These experiments contribute to our understanding of the influence of biological and topographic drivers of dung disappearance rates, and enable further advances to be made in the modelling of nutrients in these topographically complex agroecosystems.